From bravo at iol.ie Mon Sep 1 10:33:25 2003
From: bravo at iol.ie (John Tait)
Date: Mon Sep 1 07:04:28 2003
Subject: Topband: HF-2V
References: <19tUDJ-0guSB60@fwd10.sul.t-online.com>
Message-ID: <001101c37063$befab340$0100a8c0@targa>
Subject: Topband: HF-2V
> Hi all,
>
> can somebody explain to me please, how the Butternut HF-2V (with TBR-160)
actually works? I was able to figure out the "diagram" of those L's and C's
but could not work out whether they are traps or what?
What you need is at
http://www.iol.ie/~bravo/80&40mVertic.htm
73
John EI7BA
> Is there any way of improvement other than adding top loading, e.g.
placing the Ls and Cs higher in the structure or increasing the length of
the bottom tube?
>
> Thanks and 73
> Thomas, DJ5DT
> 31. Aug. 2003
>
>
>
> _______________________________________________
> Topband mailing list
> Topband@contesting.com
> http://lists.contesting.com/mailman/listinfo/topband
>
>
>
From W7lr at aol.com Mon Sep 1 10:50:37 2003
From: W7lr at aol.com (W7lr@aol.com)
Date: Mon Sep 1 11:28:22 2003
Subject: Topband: stories
Message-ID: <61.348092fc.2c84a8ad@aol.com>
Back in 1948 I didn't have the opportunity to operate on topband while on the
Hallicrafter DXpedition to British East Africa, which then was VQ3
Tanganyika, VQ4 Kenya and VQ5 Uganda. But recently PA0ABM has written stories of that
early expedition from material that I sent him, plus material from the other
operator W0LHS (who used to write the Digital Bus column in World Radio). I
thought that some of my many topband friends would like to read what dxing was
like in those days.
You can find the web address at the end of my W7LR bio in qrz.com, or at:
http://www.qsl.net/pa0abm/ghe/00ghe.htm
73 and good topband dxing. Bob W7LR
From daveN4SU at worldnet.att.net Mon Sep 1 11:34:08 2003
From: daveN4SU at worldnet.att.net (Dave Kennedy)
Date: Mon Sep 1 11:28:23 2003
Subject: Topband: A92ZE & A92GE
Message-ID: <3F538310.320A0DCB@worldnet.att.net>
Hello DXers:
This is to let it be known that Gus, K4SXT, is no longer the QSL
manager for A92ZE and David, A92GE. Gus has been reassigned
and his FPO address is no longer valid. Cards for A92ZE should
be mailed to his K4SXT Va. Beach address. See Buckmaster or
QRZ.com. Buckmaster indicates that A92GE wants cards mailed
direct to his A9 address.
73, Dave, N4SU, ("S" Sorter, ARRL K4/N4/W4 QSL Bureau
From sire at iinet.net.au Tue Sep 2 08:02:49 2003
From: sire at iinet.net.au (Steve Ireland)
Date: Mon Sep 1 20:01:22 2003
Subject: Topband: Conditions on 1st day of spring.
Message-ID: <3.0.5.32.20030902070249.00aba6b0@mail.iinet.net.au>
G'day
With the start of spring and the Lance Johnson, I spent about one and half
hours listening on 160m last night, from my sunset at 0959Z.
Although the propagation seemed limited (or activity was low - I called CQ
DX on 1827.2 for some time with no callers), W8JI and K9DX were both
peaking around 599 at their sunrises. The band seems to be waking up in VK6.
Vy 73
Steve, VK6VZ
From kt1v at demop.com Mon Sep 1 21:29:41 2003
From: kt1v at demop.com (Ted Demopoulos)
Date: Mon Sep 1 20:54:19 2003
Subject: Topband: strange QRM problem
Message-ID: <3F53E475.6090609@demop.com>
The new shack here has 3-way dimmer switches, i.e. the lights can be
dimmed/undimmed from both in the shack and from the hallway leading
there. There are almost no QRN issues with the dimmers, except on
exactly one antenna, a beverage. The QRN used to be only heard on
topband, but also seems to affect 80m a bit. Its not too bad, maybe S1,
but should be solvable somehow!
I have 3 sets of beverages and associated feedlines, and the noise only
occurs on the 1100 foot NE Beverage, which incidentally happens to start
the closest to the shack, about 150' away. I replaced all feedlines
etc, added about 20" of ferrites to the antenna end of the coax, with
no change. This Beverage does have the worst feedpoint ground of them
all as its in a rock field, but I do have 3 ground rods spaced roughly
4-6 feet and in the ground from 2.5 to 5 feet deep. All Beverages (and
other ants) come in thru the same aluminum feedthough panel.
I have two thoughts:
1)improve ground at Beverage (radials?)
2) The feedline, as its not cut to length, has a coil of maybe 100 feet
of spare length next to the feedthrough panel and maybe 15 feet from the
dimmer switches - could this be the culprit? (the previous feedline had
a similar coil about 100' from the dimmer switches - as I'm hoping to
move the Beverage further from the house).
Of course I could just get rid of the dimmer switches, but since only
one antenna is affected, I may be treating the systmes instead of the
problem by doing this??
73
Ted KT1V
From jmaass at columbus.rr.com Tue Sep 2 00:15:28 2003
From: jmaass at columbus.rr.com (Jeff Maass)
Date: Tue Sep 2 06:31:05 2003
Subject: Topband: CQ 160 CW Contest Opportunity: Curacao (PJ2)
Message-ID:
160 Ops:
The Signal Point station on Curacao, operated by the Caribbean
Contesting Consortium (CCC) as PJ2T, is available to rent for
the CQ 160 Meter CW Contest, January 24 - 25, 2004.
This was the site of the PJ2X operation in the 2003 CQ 160 CW
Contest, which finished second in high claimed scores to only
VY2ZM.
The station consists of four full-power stations, equipped with
FT1000MP, FT-1000MP Mk V, Ten Tec Omni 6, and TS-930
transceivers. Description of the stations can be found at
http://asgard.kent.edu/ccc/pj2t.station.home.page.htm
160 meter transmit antenna is an inv-L with a 75-foot vertical
component and approximately 60 radials. It works very well!
Two Beverages are now available, one 650-feet long for the
USA/JA and one 1000-feet long for Europe (new since the
PJ2X operation). A set of K9AY loops are available for
temporary installation for the contest, and we expect to
have a pair of phased pennants available, also for temporary
deployment for the contest.
For additional rental information, including other weeks the
house and station are available, see the CCC web site at:
http://asgard.kent.edu/ccc/signal.point.rental.informtion.htm.
Direct questions or reservation requests to Geoff Howard
W0CG / PJ2DX at ghoward@kent.edu.
73,
Jeff Maass K8ND
Station Committee Chairman
Caribbean Contesting Consortium - PJ2T
http://www.pj2t.org
http://home.columbus.rr.com/jmaass/Radio/PJ2T_Aerial.htm
From jmaass at columbus.rr.com Tue Sep 2 11:33:46 2003
From: jmaass at columbus.rr.com (Jeff Maass)
Date: Tue Sep 2 15:54:31 2003
Subject: Topband: FW: CQ 160 CW Contest Opportunity: Curacao (PJ2)
Message-ID:
160 Ops:
A spelling error crept into the link in the posting below!
For additional rental information, including other weeks the
house and station are available, see the CCC web site at:
http://asgard.kent.edu/ccc/signal.point.rental.information.htm.
73,
Jeff Maass K8ND
Station Committee Chairman
Caribbean Contesting Consortium - PJ2T
http://www.pj2t.org
http://home.columbus.rr.com/jmaass/Radio/PJ2T_Aerial.htm
> -----Original Message-----
> From: Jeff Maass [mailto:jmaass@columbus.rr.com]
> Sent: Monday, September 01, 2003 23:15
> To: topband mailing list
> Cc: Geoff Howard W0CG
> Subject: CQ 160 CW Contest Opportunity: Curacao (PJ2)
>
>
>
> 160 Ops:
>
> The Signal Point station on Curacao, operated by the Caribbean
> Contesting Consortium (CCC) as PJ2T, is available to rent for
> the CQ 160 Meter CW Contest, January 24 - 25, 2004.
>
> This was the site of the PJ2X operation in the 2003 CQ 160 CW
> Contest, which finished second in high claimed scores to only
> VY2ZM.
>
> The station consists of four full-power stations, equipped with
> FT1000MP, FT-1000MP Mk V, Ten Tec Omni 6, and TS-930
> transceivers. Description of the stations can be found at
> http://asgard.kent.edu/ccc/pj2t.station.home.page.htm
>
> 160 meter transmit antenna is an inv-L with a 75-foot vertical
> component and approximately 60 radials. It works very well!
>
> Two Beverages are now available, one 650-feet long for the
> USA/JA and one 1000-feet long for Europe (new since the
> PJ2X operation). A set of K9AY loops are available for
> temporary installation for the contest, and we expect to
> have a pair of phased pennants available, also for temporary
> deployment for the contest.
>
> For additional rental information, including other weeks the
> house and station are available, see the CCC web site at:
> http://asgard.kent.edu/ccc/signal.point.rental.informtion.htm.
>
> Direct questions or reservation requests to Geoff Howard
> W0CG / PJ2DX at ghoward@kent.edu.
>
> 73,
> Jeff Maass K8ND
>
> Station Committee Chairman
> Caribbean Contesting Consortium - PJ2T
> http://www.pj2t.org
> http://home.columbus.rr.com/jmaass/Radio/PJ2T_Aerial.htm
>
From smlx at earthlink.net Tue Sep 2 19:57:56 2003
From: smlx at earthlink.net (Steve Lawrence)
Date: Tue Sep 2 23:51:19 2003
Subject: Topband: New BPL trial in Pennsylvania
Message-ID: <09B286C4-DDB2-11D7-B4CF-0003931129C6@earthlink.net>
For those of you in Hanover Township, Northampton County, PA. BPL
coming your way:
http://www.mcall.com/business/local/all-
plcaug30,0,2245525.story?coll=all-businesslocal-hed
73, Steve WB6RSE
From kb5njd at netzero.com Tue Sep 2 22:39:09 2003
From: kb5njd at netzero.com (John Langridge)
Date: Tue Sep 2 23:51:20 2003
Subject: Topband: rx antenna switch
Message-ID:
I think someone mentioned quite a while ago that they used a simple radio
shack A/B or A/B/C pushbutton switch designed for vcr/cable to switch their
receive antennas. I skimmed through the archives hoping to chance upon the
thread but suspect that the mention was only incidental, embedded within
another thread.
I purchased one of the "newer" models this past weekend and found that when
I hooked it up, there were no signals whatsoever. The cables and connectors
were fine and there was plenty of signal when I took the switch out of line.
Thinking I had a bad unit, I took it back only to find that the unit I had
was the last one in stock. Instead of bringing it back home and opening it
up to see what was inside, I returned it on the spot.
Has anyone actually used one of these switches successfully for this
purpose? Could the fact that they are advertised as "high isolation"
indicate that these are not just simple switches and may not pass a signal
in the HF/MF range?
Thanks in advance for any info you might have.
John KB5NJD
From K4SV2 at Charter.net Wed Sep 3 00:25:41 2003
From: K4SV2 at Charter.net (Dave Anderson, K4SV)
Date: Tue Sep 2 23:51:21 2003
Subject: Topband: Rohn Tower for 160/80 antenna
Message-ID: <007601c371cb$0db96720$64016c5a@HAM>
Hi All,
Wanted to ask if the normal calculation for a 1/4 vertical applies (234/F(mhz) = Feet of antenna for 160 meters using a Rohn 25G section of tower for the radiator (125 foot)?
Second part.
If I made the bottom a 60 feet Rohn 25G tower section with 50 foot of tapered AL tubing and a small inductor to resonate all sitting on insulators, would there be a better calculation for length? Has anyone tried this? What is better? Yeah I know, a 2 element beam for 160, but it wont fit the backyard.
Thanks in advance,
Dave, K4SV
Asheville, NC
From R.Gorski at Astronautics.com Wed Sep 3 09:03:27 2003
From: R.Gorski at Astronautics.com (Ronald Gorski)
Date: Wed Sep 3 10:47:45 2003
Subject: Topband: rx antenna switch
In-Reply-To:
Message-ID: <5.1.0.14.1.20030903075506.00a09640@Mailhost.Astronautics.com>
I have used this type of switch for years with varying success. The older
style (square pushbuttons) of A/B or A/B/C switch has a more positive
"feel" when the switch engages. The newet style is a bit more "mushy". Both
styles have significant isolation when used to switch receive antennas
and/or preamps. I have had some switch failures through the years but have
never disassembled same for failure analysis; just replaced the switch as
the cost is low. Ron N9AU
At 09:39 PM 9/2/03 -0500, John Langridge wrote:
>I think someone mentioned quite a while ago that they used a simple radio
>shack A/B or A/B/C pushbutton switch designed for vcr/cable to switch their
>receive antennas. I skimmed through the archives hoping to chance upon the
>thread but suspect that the mention was only incidental, embedded within
>another thread.
>
>I purchased one of the "newer" models this past weekend and found that when
>I hooked it up, there were no signals whatsoever. The cables and connectors
>were fine and there was plenty of signal when I took the switch out of line.
>Thinking I had a bad unit, I took it back only to find that the unit I had
>was the last one in stock. Instead of bringing it back home and opening it
>up to see what was inside, I returned it on the spot.
>
>Has anyone actually used one of these switches successfully for this
>purpose? Could the fact that they are advertised as "high isolation"
>indicate that these are not just simple switches and may not pass a signal
>in the HF/MF range?
>
>Thanks in advance for any info you might have.
>
>John KB5NJD
>
>_______________________________________________
>Topband mailing list
>Topband@contesting.com
>http://lists.contesting.com/mailman/listinfo/topband
From k6se at juno.com Wed Sep 3 08:24:38 2003
From: k6se at juno.com (Earl W Cunningham)
Date: Wed Sep 3 10:47:47 2003
Subject: Topband: Rohn Tower for 160/80 antenna
Message-ID: <20030903.073453.-1836029.0.k6se@juno.com>
Dave, K4SV asked:
"Wanted to ask if the normal calculation for a 1/4 vertical applies
(234/F(mhz) = Feet of antenna for 160 meters using a Rohn 25G section of
tower for the radiator (125 foot)?"
==========
13 sections of Rohn 25G is 126' 6" and will be resonant at 1845 kHz over
a good ground radial system per my EZNEC tower models. A 3-foot
"stinger" on top of that will bring it down to 1830 kHz.
73, de Earl, K6SE
From k6se at juno.com Wed Sep 3 09:00:40 2003
From: k6se at juno.com (Earl W Cunningham)
Date: Wed Sep 3 13:37:33 2003
Subject: Topband: Rohn Tower for 160/80 antenna
Message-ID: <20030903.080041.-1836029.2.k6se@juno.com>
Dave, K4SV asked:
"Wanted to ask if the normal calculation for a 1/4 vertical applies
(234/F(mhz) = Feet of antenna for 160 meters using a Rohn 25G section of
tower for the radiator (125 foot)?"
==========
On the other hand, if the 13 sections of Rohn 25G (126' 6") is sitting on
top of 6" insulators and is fed at the bottom of one leg, it will be
resonant at 1831 kHz without any "stinger" on top (per my tower models).
In my previous post, the tower was fed with equal currents to each of the
three legs. This post is probably more practical and accurate.
73, de Earl, K6SE
From herbs at vitelcom.net Wed Sep 3 13:38:50 2003
From: herbs at vitelcom.net (Herb Schoenbohm)
Date: Wed Sep 3 13:37:34 2003
Subject: Topband: Series Fed vs Shunt Fed Towers
Message-ID: <3F560B0A.8060703@vitelcom.net>
Over the past week several interesting comments were made on the
advantages of a shunt fed tower over a direct fed insulated tower. I
was convinced long ago after listening to the John Mulaney (Mulaney and
Associates) that a folded monopole has significant advantages in several
important areas for the topbander including; lightning protection,
simplicity of matching, increased radiation efficiency, and increased
bandwidth. In 1996 Ron Rackley along with Bobby Cox, James Moser and
Tom King of Kintronics presented a paper at the NAB convention entitled
"An Efficiency Comparison: AM/Medium Wave Vs. Skirt Fed Radiators."
(http://www.dlr.com/dlrweb/papers/nabpaper/nabpaper.htm) Most amateurs I
have talk to about this use single wire shunt feeds, rather than a three
or four wire cage, of #10 wire or larger. Depending upon spacing
considerations of that single wire, sometimes results are not as
convincing and matching becomes difficult.
The writers of the paper also tested the difference between a
120-radial, 30-radial and a single ground rod for a tower of 98.3
degrees and 61.5 degrees electrical height. All experimental tests were
conducted on 1680 Khz with 400 watts while modeling used the NEC-4.1
developed by Dr. Gerald Burke of Lawrence Livermore National Laboratory.
To summarize briefly their findings:
(1) No major differences in field strength between the folded unipole
and series fed test cases.
(2) The folded unipole was not found to have a significantly better
radiation efficiency than the series fed for a given tower and ground
system.
(3) No major differences in bandwidth for either system except when a
skirted series fed tower has the skirt connected at both top and bottom.
The paper is 11 pages long and is a must read especially for persons
wanting to decide which way to proceed in tower construction. Of course
the shunt fed tower is a better choice for anyone wanting to mount beams
and other antennas which seems to be the case in most of the amateur
applications.
73
Herb Schoenbohm, KV4FZ
From ve3zi at yahoo.com Thu Sep 4 04:14:47 2003
From: ve3zi at yahoo.com (=?iso-8859-1?q?Roger=20Parsons?=)
Date: Wed Sep 3 22:37:26 2003
Subject: Topband: End or Centre Feed?
Message-ID: <20030904021447.27995.qmail@web14910.mail.yahoo.com>
There is a vague possibility that I may get the W4RNL
array up before the snow flies. This is a half wave
vertical parasitic array. I could practically feed the
middle driven element at the base or at the centre.
According to EZNEC, the 3:1 SWR bandwidth is about the
same with either feed method, and at the base the feed
impedance is roughly 3000 Ohms at resonance, with
major reactive components as I move away. At the
centre the feed impedance is roughly 8 Ohms with the
same situation as I move away. The gain and pattern
are the same in either case.
Seems to me that the pros and cons are:
End Feed:
Very high voltages, and potentially very high losses
if I get the matching network even a little wrong;
The possibility of providing a DC ground and a spark
gap;
When the practical antenna is not quite the same as
the model the matching network can be easily adjusted
- there is no feedline so no high SWR on the feedline;
Potentially more chance of rf in the shack although
the ground system is so extensive that I doubt this
will be a problem.
Centre Feed:
I could use a 1:9 (Z) balun at the feed point to give
a reasonable match to 75 Ohm hardline at resonance;
The balun would be seeing a reactive load off
resonance - not sure how it would like that;
The matching network would be at ground level so there
could be a high SWR on the hardline, but the matching
network would have quite an easy job;
In practice the antenna would not be resonant exactly
at the design frequency, so the match (at the antenna)
would quite likely never be perfect at any frequency
actually used;
I could raise the whole antenna an extra 20ft above
the ground which according to EZNEC gives me a
fraction of a dB more gain....;
DC ground could be at centre of element through a
balun, so presumably not so good as at the base.
Would be grateful for any thoughts.
73 Roger
VE3ZI
________________________________________________________________________
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From W4EF at dellroy.com Thu Sep 4 11:41:16 2003
From: W4EF at dellroy.com (Michael Tope)
Date: Thu Sep 4 14:04:42 2003
Subject: Topband: rx antenna switch
References: <5.1.0.14.1.20030903075506.00a09640@Mailhost.Astronautics.com>
Message-ID: <09ae01c3730b$be772660$0100a8c0@1800XP>
The ones I have taken apart are just simple mechanical switches
and as such should work fine down to DC. Isolation at VHF and
UHF is typically a minimum of 75dB. At 1.8 MHz its probably
in excess of 100dB. These should make very good RX switches
for topband.
Mike, W4EF................................
----- Original Message -----
From: "Ronald Gorski"
To: ;
> I have used this type of switch for years with varying success. The older
> style (square pushbuttons) of A/B or A/B/C switch has a more positive
> "feel" when the switch engages. The newet style is a bit more "mushy".
Both
> styles have significant isolation when used to switch receive antennas
> and/or preamps. I have had some switch failures through the years but have
> never disassembled same for failure analysis; just replaced the switch as
> the cost is low. Ron N9AU
>
> At 09:39 PM 9/2/03 -0500, John Langridge wrote:
> >I think someone mentioned quite a while ago that they used a simple radio
> >shack A/B or A/B/C pushbutton switch designed for vcr/cable to switch
their
> >receive antennas. I skimmed through the archives hoping to chance upon
the
> >thread but suspect that the mention was only incidental, embedded within
> >another thread.
> >
> >Has anyone actually used one of these switches successfully for this
> >purpose? Could the fact that they are advertised as "high isolation"
> >indicate that these are not just simple switches and may not pass a
signal
> >in the HF/MF range?
> >
From brehm at ptitest.com Thu Sep 4 15:17:41 2003
From: brehm at ptitest.com (Brad Rehm)
Date: Thu Sep 4 14:52:34 2003
Subject: Topband: rx antenna switch
References: <5.1.0.14.1.20030903075506.00a09640@Mailhost.Astronautics.com>
<09ae01c3730b$be772660$0100a8c0@1800XP>
Message-ID: <005c01c37319$3bc3cc10$456fa8c0@3vlf901>
>Has anyone actually used one of these switches successfully for this
>purpose? Could the fact that they are advertised as "high isolation"
>indicate that these are not just simple switches and may not pass a
signal
>in the HF/MF range?
A few years ago, I met the designer of a few of these Radio Shack
switches. He happened to mention that they had paid close attention
to maintaining constant impedance and achieving good port-to-port
isolation in the design. There were no networks or gimmicks in the
switches he had been associated with. From business associations, I
know there are some good RF guys in the Tandy Towers in Fort Worth.
The only problem I've had with one of my switches has been that the
mechanism goes bad and the switch stops toggling. But they're not
expensive....
The fact that they're 75 Ohm devices shouldn't be important for top
band applications.
73,
Brad
KV5V
From dwilborg at bit-net.com Thu Sep 4 17:22:34 2003
From: dwilborg at bit-net.com (Dick Wilborg)
Date: Thu Sep 4 16:44:44 2003
Subject: Topband: rx antenna switch
In-Reply-To: <005c01c37319$3bc3cc10$456fa8c0@3vlf901>
Message-ID:
In fact, the Radio Shack A/B & A/B/C TV switches are quite good. What makes
them especially useful is the fact that in addition to 100+ db isolation
between ports, the unselected ports are automatically internally terminated
into 75 ohms!
The only problem I have occasionally had is the internal 75 ohm resistors
get burned from nearby lightning. Sometimes repairable! Otherwise, just
buy another.
Great for Beverages!
Cheers, Dick W1ZC
-----Original Message-----
From: topband-bounces@contesting.com
[mailto:topband-bounces@contesting.com]On Behalf Of Brad Rehm
Sent: Thursday, September 04, 2003 3:18 PM
To: Michael Tope; kb5njd@arrl.net; topband@contesting.com; Ronald Gorski
Subject: Re: Topband: rx antenna switch
>Has anyone actually used one of these switches successfully for this
>purpose? Could the fact that they are advertised as "high isolation"
>indicate that these are not just simple switches and may not pass a
signal
>in the HF/MF range?
A few years ago, I met the designer of a few of these Radio Shack
switches. He happened to mention that they had paid close attention
to maintaining constant impedance and achieving good port-to-port
isolation in the design. There were no networks or gimmicks in the
switches he had been associated with. From business associations, I
know there are some good RF guys in the Tandy Towers in Fort Worth.
The only problem I've had with one of my switches has been that the
mechanism goes bad and the switch stops toggling. But they're not
expensive....
The fact that they're 75 Ohm devices shouldn't be important for top
band applications.
73,
Brad
KV5V
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From thompson at mindspring.com Thu Sep 4 22:48:16 2003
From: thompson at mindspring.com (David L. Thompson)
Date: Thu Sep 4 21:52:58 2003
Subject: Topband: 2003 CQ 160 Logs Not Received
Message-ID: <5.2.1.1.0.20030904214710.026b0c50@pop.vnet.net>
Here are the calls that were found on the 3830 list for the 2003 CQ 160
Contests. No log was found at either Trey's robot or on my PC. Logs will
be accepted at k4jrb@juno.com only and please send along any possible
confirmation number.
CW Logs SSB Logs
AA0RS M/O W9SMC S/O HP
W5VX S/O HP AA0RS S/O HP
K1PQS S/O HP AC8G S/O HP
WQ5L S/O HP KC7V S/O HP
KI9A S/O HP W0RK S/O HP
K2AV S/O HP NA4K S/O LP
K2AV S/O HP N3RA S/O LP
N8UM S/O LP WA4PGM S/O QRP
K4TX S/O LP
K8LV S/O LP
N3SD S/O LP
VE9DX S/O LP
N3RA S/O LP
KL2A/7 S/O LP
CW DX
LY2BIL M/O
S55M S/O HP
DL7BY S/O LP
SY8A S/O LP
LZ8T S/O QRP
Dave K4JRB CQ 160 Director
From bernie at dailydx.com Fri Sep 5 21:38:15 2003
From: bernie at dailydx.com (Bernie McClenny, W3UR)
Date: Fri Sep 5 17:02:02 2003
Subject: Topband: 160 meters ZB2FK
Message-ID: <001201c373ed$a4d3c050$6401a8c0@pavilion>
Ernie, ZB2FK, says he will be on 160 meters tonight after 2300Z on or
about 1825. This is Friday GMT 2300Z. Too early for the US but that is
another story.
Bernie
--
Bernie McClenny, W3UR
Editor of The Daily DX, The Weekly DX and How's DX.
http://www.dailydx.com
From w4an at contesting.com Fri Sep 5 17:50:24 2003
From: w4an at contesting.com (Bill Fisher, W4AN)
Date: Fri Sep 5 17:02:03 2003
Subject: Topband: Contesting.com Mailing Lists Users
Message-ID: <048b01c373ef$54d79b60$de0a0a0a@billxp>
Hello all,
Last August we started taking voluntary "subscriptions" in an effort to pay for the costs of running the Contesting.com and eHam.net web sites.
Reference: http://lists.contesting.com/_topband/2002-August/015269.html
The subscriptions this past year have really helped. We were able to purchase a new server for the Contesting.com mailing lists as well as a new database server for eHam.net (2 servers now deliver more than 5 million pages per month). Money from advertising has pretty much remained constant, so the subscriptions were the only thing that made a difference.
We have defined an annual subscription program for which site & mailing list users can voluntarily help pay for operations. We don't define the amount of the subscription, but rather suggest that each user define for themselves the site's value, and consider their own financial ability to subscribe. For instance, you might compare how much time you spend reading QST or CQ magazines with how much time you spend reading eHam.net & Contesting.com mailing lists.
If you are a frequent user and have the ability, You can help by subscribing at http://www.eham.net/about/sponsors. There are links to pay online with a credit card, by PayPal or information on sending a check.
Thanks very much for helping out.
73
Bill Fisher, W4AN
From btippett at alum.mit.edu Fri Sep 5 18:15:26 2003
From: btippett at alum.mit.edu (Bill Tippett)
Date: Fri Sep 5 17:18:52 2003
Subject: Topband: Contesting.com Mailing Lists Users
Message-ID: <6.0.0.22.0.20030905171520.030e6e90@pop.vnet.net>
Bill W4AN made a mistake in the link for
contributions...try this one:
http://www.eham.net/about/sponsors
As Bill says, think about what benefit you receive
from contesting.com reflectors and also eHam.net,
and then consider a contribution. I sold enough
gear on eHam Classifieds to pay for a new Orion,
and can attest the Classifieds really work well!
73, Bill W4ZV
From peterc at starhub.com Sat Sep 6 15:06:45 2003
From: peterc at starhub.com (Peter John COOK)
Date: Sat Sep 6 06:16:51 2003
Subject: Topband: S61FD St John's Island Singapore
Message-ID:
Folks,
Bob (G4VGO) and I are now QRV with a good 30m high inv L for topband and
full quarterwave for 80m and low noise RX pennants.
Bad condx last night but listen out for us on 1826.5 and 3505.5.
Operational all nights until sunrise Monday 8th Sept,
73
Peter 9V1PC
This email is confidential and privileged. If you are not the intended
recipient, you must not view, disseminate, use or copy this email. Kindly
notify the sender immediately, and delete this email from your system. Thank
you.
Please visit our website at www.starhub.com
From K1ZM at aol.com Sat Sep 6 07:31:16 2003
From: K1ZM at aol.com (K1ZM@aol.com)
Date: Sat Sep 6 07:29:03 2003
Subject: Topband: Critters Eating Coax
Message-ID: <77.184f00d2.2c8b1174@aol.com>
I wonder if anyone on the reflector knows of a remedy that will stop
squirrels from eating the black jacket from Rg213 coax?
They seem to love the stuff and eat hundreds of feet of the black PVC jacket
half way around. In areas where the coax is elevated (and they can reach all
of it) they eat it ALL THE WAY ROUND! They stop at the braid (usually) but
the resulting water intrusion ruins the coax (ultimately).
At some point I am going to have to replace quite a bit of coax but, before I
do, I wonder if anyone knows of a way to keep the little hungry buggers off
of it....
Any known solutions out there that WORK? Is there some substance that the
critters really do not like that can be applied to the coax - a spray or jelly
perhaps?
Many thanks for reading.
73 JEFF
K1ZM@aol.com
From btippett at alum.mit.edu Sat Sep 6 08:40:52 2003
From: btippett at alum.mit.edu (Bill Tippett)
Date: Sat Sep 6 07:41:41 2003
Subject: Topband: Critters Eating Coax
Message-ID: <6.0.0.22.0.20030906073511.02ba6310@pop.vnet.net>
Jeff and all,
Lots of info on this in the archives...on Google
try searching site:dayton.akorn.net critter
Here's a good summary post by N8UG (aka The Wireman):
http://dayton.akorn.net/pipermail/towertalk/1998-April/013489.html
BTW, Google has a new toolbar which will allow you to search
only the current site in your browser. It automatically generated
the "site:dayton.akorn.net" above which restricts the search to
all of the contesting.com reflectors.
73, Bill W4ZV
From fcresce at comcast.net Sat Sep 6 08:54:25 2003
From: fcresce at comcast.net (Fred Cresce)
Date: Sat Sep 6 10:18:47 2003
Subject: Topband: Critters Eating Coax
Message-ID: <001b01c3746d$9eefd180$6401a8c0@DJZJV911>
Hello fellow 160 guys,
The band is showing some life after a very noisy Summer. I have a wooded lot and the squirrels aren't bothering any of my stuff. I have lots of RG-213 out there and no nibbles, now I set out oil Sunflower seeds every day and maybe that distracts them from my coax. Just my 2 cents
I'll check the link mentioned in Bill's post.
Fred KC4MOP
From geoiii at kkn.net Sat Sep 6 08:37:26 2003
From: geoiii at kkn.net (George Fremin III)
Date: Sat Sep 6 10:18:49 2003
Subject: Topband: Archives
In-Reply-To: <6.0.0.22.0.20030906073511.02ba6310@pop.vnet.net>
References: <6.0.0.22.0.20030906073511.02ba6310@pop.vnet.net>
Message-ID: <20030906123726.GB17966@kkn.net>
On Sat, Sep 06, 2003 at 07:40:52AM -0400, Bill Tippett wrote:
>
> Lots of info on this in the archives...on Google
> try searching site:dayton.akorn.net critter
> Here's a good summary post by N8UG (aka The Wireman):
Speaking of searchable archives - I have been working on
getting new and improved archives setup for the lists.
If anyone wants to give them a try you can find them here:
http://lists.contesting.com/archives/
The topband archive is here:
http://lists.contesting.com/archives//html/Topband/
--
George Fremin III - K5TR
geoiii@kkn.net
http://www.kkn.net/~k5tr
From NX4D at comcast.net Sat Sep 6 10:23:09 2003
From: NX4D at comcast.net (Doug Waller)
Date: Sat Sep 6 10:18:50 2003
Subject: Topband: Critters Eating Coax
References: <77.184f00d2.2c8b1174@aol.com>
Message-ID: <008a01c3747a$066dff10$f39a3b44@youry5sn6dl7l3>
> Any known solutions out there that WORK? Is there some substance that the
> critters really do not like that can be applied to the coax - a spray or
jelly
> perhaps?
> 73 JEFF
Squirrels hate the taste of coax! But they are apparently driven by nature
to intake compounds missing in their diet. After rains I have noticed the
squirrels licking my coax, and the treated & stained wood deck.
It took alot of mulling this over, but the realization finally came that
they probably needed a cattle salt block to supplement their little diets.
A salt block by the tower was ignored until buried in the ground with a thin
sand layer over it, and then watered. There is now a steady stream of
squirrels to the newly discovered salt lick block, and they seem to have
lost interest in my coax, the deck and some hot peppers nearby.
This solution could be a two-edge sword however, as I have noticed raccoon &
fox tracks.......and the squirrels are growing! I would suggest placing the
salt block away from coax areas to draw the "gnawers" away rather than to
the area to be protected.
While I can not guarantee this will work for everyone, given individual
squirrel personalities & regional tastes, it could be an easy solution to a
gnawing problem for many.
73, Doug / NX4D
From k4kyv at hotmail.com Sat Sep 6 18:12:54 2003
From: k4kyv at hotmail.com (Donald Chester)
Date: Sat Sep 6 14:13:49 2003
Subject: Topband: Critters Eating Coax
Message-ID:
>I wonder if anyone on the reflector knows of a remedy that will stop
>squirrels from eating the black jacket from Rg213 coax?
>
I have had the same problem with critters (probably rodents) eating the
jacket from buried RG-214. I replaced mine with RG-213 rated for direct
burial, but have not checked recently for damage.
Don K4KYV
_________________________________________________________________
Need more e-mail storage? Get 10MB with Hotmail Extra Storage.
http://join.msn.com/?PAGE=features/es
From va3xrz at qsl.net Sat Sep 6 16:58:34 2003
From: va3xrz at qsl.net (VA3XRZ [Q])
Date: Sat Sep 6 20:57:35 2003
Subject: Topband: Critters Eating Coax
References: <001b01c3746d$9eefd180$6401a8c0@DJZJV911>
Message-ID: <002401c374b1$455c0dc0$010a0a0a@cx9ct>
Same here, I have tons of coax and wildlife running around the backyard and
never had any problem with squirrels or chipmunks damaging anything but my
wife keeps a couple of plates on the deck full of assorted seeds for the
wildlife to help themselves.
Julio VA3XRZ
----- Original Message -----
From: "Fred Cresce"
To: "Top Band Reflector"
Sent: Sat 06-Sep-2003 07:54
Subject: Topband: Critters Eating Coax
Hello fellow 160 guys,
The band is showing some life after a very noisy Summer. I have a wooded lot
and the squirrels aren't bothering any of my stuff. I have lots of RG-213
out there and no nibbles, now I set out oil Sunflower seeds every day and
maybe that distracts them from my coax. Just my 2 cents
I'll check the link mentioned in Bill's post.
Fred KC4MOP
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From W1JR at arrl.net Sat Sep 6 16:39:53 2003
From: W1JR at arrl.net (Joe Reisert)
Date: Sat Sep 6 20:57:37 2003
Subject: Topband: Critters Eating Coax
In-Reply-To:
Message-ID: <6.0.0.14.2.20030906153514.030f8a50@mailhost.jlc.net>
Hi Jeff,
Same problem here except it's mostly chipmunks and they can only eat
completely the small diameter coax. They even ate though my RG141 teflon coax!
What I did is to put EMT (from the hardware store which comes in 10 foot
lengths and inexpensive) over the areas where they were most active. No
more problems in those areas.
It's probably salt from your hands on the coax. Try rubbing down the coax
with acetone and see what happens. Hopefully acetone wont dissolve the coax hi.
73,
Joe, W1JR
At 01:12 PM 9/6/2003, Donald Chester wrote:
>>I wonder if anyone on the reflector knows of a remedy that will stop
>>squirrels from eating the black jacket from Rg213 coax?
>
>I have had the same problem with critters (probably rodents) eating the
>jacket from buried RG-214. I replaced mine with RG-213 rated for direct
>burial, but have not checked recently for damage.
>
>Don K4KYV
>
>_________________________________________________________________
>Need more e-mail storage? Get 10MB with Hotmail Extra Storage.
>http://join.msn.com/?PAGE=features/es
>
>_______________________________________________
>Topband mailing list
>Topband@contesting.com
>http://lists.contesting.com/mailman/listinfo/topband
From garry at ni6t.com Sat Sep 6 16:30:12 2003
From: garry at ni6t.com (Garry Shapiro)
Date: Sat Sep 6 20:57:38 2003
Subject: Topband: Critters Eating Coax
In-Reply-To: <77.184f00d2.2c8b1174@aol.com>
Message-ID:
Jeff:
At least one of the wire and cable vendors selling to the ham community
claims that polyethylene jackets are less attractive to critters than PVC
jackets. I bought and installed some polyethylene-jacket coax when I found
one of my longer lines gnawed--I live in a redwood forest with lots of
critters--and that line has not been gnawed. Not exactly a controlled
study--but it's the best I can do on short notice.
Garry, NI6T
-----Original Message-----
From: topband-bounces@contesting.com
[mailto:topband-bounces@contesting.com]On Behalf Of K1ZM@aol.com
Sent: Saturday, September 06, 2003 3:31 AM
To: topband@contesting.com
Subject: Topband: Critters Eating Coax
I wonder if anyone on the reflector knows of a remedy that will stop
squirrels from eating the black jacket from Rg213 coax?
They seem to love the stuff and eat hundreds of feet of the black PVC jacket
half way around. In areas where the coax is elevated (and they can reach
all
of it) they eat it ALL THE WAY ROUND! They stop at the braid (usually) but
the resulting water intrusion ruins the coax (ultimately).
At some point I am going to have to replace quite a bit of coax but, before
I
do, I wonder if anyone knows of a way to keep the little hungry buggers off
of it....
Any known solutions out there that WORK? Is there some substance that the
critters really do not like that can be applied to the coax - a spray or
jelly
perhaps?
Many thanks for reading.
73 JEFF
K1ZM@aol.com
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From rts13 at digitalusa.net Sat Sep 6 23:35:45 2003
From: rts13 at digitalusa.net (rts13)
Date: Sun Sep 7 06:20:55 2003
Subject: Topband: Re: Critters eating coax
Message-ID: <005201c374e8$bf75a9e0$8b17f5cd@CAT>
Ahoy Topbanders:
Ever notice the squirrel or chipmunk rodents eating on a garden
hose?
Try a garden hose sleeve over the RG-213 size, or smaller, coax.
73, Pete K4LDR Citrus County, FL
From w8ji at contesting.com Sun Sep 7 12:01:29 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Sun Sep 7 14:05:02 2003
Subject: Topband: 1820 Intruder
Message-ID: <001d01c37550$ec0cc840$288001d8@akorn.net>
There is a slowly off-and-on keyed "buzzy" signal just above 1820kHz that
K9DX, AA1K, and myself are hearing.
It is slightly south of due east from K9DX, southwest of AA1K, and almost
exactly NE of my location (I'm ~30mi NW of Macon GA) .
I didn't look up John and Jon's locations, but I'm around 33 03 N and 84 04
W.
Perhaps this places the source somewhere within a few hundred miles of
Washington DC.
Perhaps someone closer might hear it when mobile or during the daytime, or
we can get some other directional headings.
73 Tom
From dennis.peterson at machlink.com Sun Sep 7 15:33:40 2003
From: dennis.peterson at machlink.com (dennis peterson)
Date: Sun Sep 7 16:37:54 2003
Subject: Topband: frequency allocations
Message-ID: <000501c37576$f0fb5620$520acf42@machlink.com>
Attention Topbanders;
It is time for me to update the frequency allocations tables on my web
site. If you have or are aware of any changes, deletions or additions
please send them to me ASAP so I may update the listing for all to use.
Thanks
Dennis/K?CKD
Dennis G. Peterson
S U R E ---
Skills Unlimited Resources Enterprise
Home, Lawn & SENIOR Services
http://www.machlink.com/~sure my business web site
http://www.machlink.com/~k0ckdennis amateur radio web site
http://www.machlink.com/~classof63 class of 1963 web site
cell:?????? 563-299-4224
home:??? 563-263-2272
---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.514 / Virus Database: 312 - Release Date: 8/28/03
From althoff at verizon.net Mon Sep 8 18:04:18 2003
From: althoff at verizon.net (Tom A)
Date: Mon Sep 8 19:21:10 2003
Subject: Topband: Critters Eating Coax
References: <001b01c3746d$9eefd180$6401a8c0@DJZJV911>
Message-ID: <003901c3764c$c4bc6960$6501a8c0@LAPTOP>
Hmmm...we do the same thing here in Greenwood Lake, NY. My both my runs of
213 for the 80/160 dipoles lay on the ground along side the pile of black
oil sunflower seeds we feed to our Cardinals (and a dozen or so sqirrels and
a couple of chipmunks). Given a choice between the coax and the seeds..the
squirrels go for the seed.
So I suspect there are two approaches...make the coax taste bad or make
something else taste better!
73 de Tom K2TA
----- Original Message -----
From: "Fred Cresce"
To: "Top Band Reflector"
Sent: Saturday, September 06, 2003 7:54 AM
Subject: Topband: Critters Eating Coax
Hello fellow 160 guys,
The band is showing some life after a very noisy Summer. I have a wooded lot
and the squirrels aren't bothering any of my stuff. I have lots of RG-213
out there and no nibbles, now I set out oil Sunflower seeds every day and
maybe that distracts them from my coax. Just my 2 cents
I'll check the link mentioned in Bill's post.
Fred KC4MOP
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From wb6rse at earthlink.net Mon Sep 8 18:43:50 2003
From: wb6rse at earthlink.net (Steve Lawrence)
Date: Mon Sep 8 22:35:01 2003
Subject: Topband: KM9D in YJ
Message-ID:
Info for the deserving from Mike KM9D. - 73, Steve WB6RSE
I have been off-the-air, waiting for a local license to transmit, since
arriving Port Vila, Vanuatu.
I wish to make a small radio expedition, while visiting Vanuatu, that
will be meaningful to IOTA collectors. We hope to make our way to the
far north of the country and visit the Torres Island group before we
earnestly consider any operation.
I will make every effort to be QRV on all of the bands before we finish.
73 for now,
de Mike
From btippett at alum.mit.edu Tue Sep 9 21:19:18 2003
From: btippett at alum.mit.edu (Bill Tippett)
Date: Tue Sep 9 20:21:45 2003
Subject: Topband: Urgent help - BQ9P
Message-ID: <6.0.0.22.0.20030909200825.03617b30@pop.vnet.net>
As many of you probably know, Dietmar DL3DXX will
be going on the BQ9P expedition October 9-16. He will be
taking a Titanex and equipment, but needs a good preamp
and matching transformer for a K9AY/Flag/Pennant RX antenna.
Problem is that no USA are signed up so far and the expedition
is only 1 month away. Current ops are BV4FH, BV3FG, BV3BW,
JI6KVR, DL3DXX, DK7YY, OE1WHC, ZL4PO and BV3/UA3VCS.
Are there any of our overseas readers who could get a
preamp (especially) to Dietmar or BV4FH within 1 month? Dietmar
can be reached at Kasper@zmd.de The preamp is especially
needed since he may be able to construct the matching
transformer. He always does a super job on 160 (e.g. ST0RY
most recently) and I hope someone can help!
Thanks & 73,
Bill W4ZV
From mccapr at myrealbox.com Wed Sep 10 11:59:57 2003
From: mccapr at myrealbox.com (Jon Rudy-MCC Asia Peace Resource)
Date: Wed Sep 10 06:08:26 2003
Subject: Topband: preamp
Message-ID: <001a01c37747$cbe6f4c0$0200a8c0@jon>
Dietmar:
I understand you need a preamp for the upcoming BQ9P DXpedition for low band. I have an extra and even a transformer for pennant laying around. I live in Davao Philippines but will be going to Cambodia through Singapore this weekend. Any connections there that could get you the goodies?
The preamp needs a 220/120 vold adapter.
jon
================================
Jon Rudy
DU9/N0NM
Davao City, Mindanao, Philippines
Zone 27, Grid-PJ27, OC-130
EX: 3DA0CA, C91CO, ZS5UZ, A2/ZS5UZ
QSL via W4DR
E-mail: n0nm@arrl.net
=================================
From w8ji at contesting.com Wed Sep 10 09:28:02 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Wed Sep 10 08:30:40 2003
Subject: Topband: 1820+ buzz
Message-ID: <001d01c37796$fb10fc60$268001d8@akorn.net>
It looks like this signal is narrowing down to the WVA /Md area. Any other
input would be appreciated.
73, Tom W8JI
From btippett at alum.mit.edu Wed Sep 10 11:50:32 2003
From: btippett at alum.mit.edu (Bill Tippett)
Date: Wed Sep 10 10:52:18 2003
Subject: Topband: Fwd: AW: Urgent help - BQ9P
Message-ID: <6.0.0.22.0.20030910104825.030e7660@pop.vnet.net>
Wow!!!...problem solved and thanks to everyone who
offered help to DL3DXX. Now all we need to do is pray for
some decent propagation!
73, Bill W4ZV
>Hi Bill
>thank you for your mail. I got half dozen offers to help. I choosed
>Carsten, DL6LAU, who has an original K9AY loop inclusive boxes. That
>gives me the time to test it out at home, as I will have it in two
>or 3 days. Thank you all the others for help.
>
>73, Dietmar
>DL3DXX
From gordondurk at knology.net Wed Sep 10 15:23:10 2003
From: gordondurk at knology.net (Don Durk, ka1dwx)
Date: Wed Sep 10 10:52:36 2003
Subject: Topband: 160 Beacons?Resource?
Message-ID: <000801c377a7$11763870$3834d618@presario>
Any details re the following beacons(?) : 1818.9 3ZCU 0445Z; 3ZDA 1829 0100Z and BHBEE 1831.1 0400Z? Any idea of QTH's or what they are for? Can someone pass along a good resource for beacon or other 'authorized' international and domestic signal sources for 160? I've tried most of the net resources with little luck. Tnx, Don Durk, ka1dwx/4
gordondurk@knology.net
From k7rx at comcast.net Wed Sep 10 16:49:43 2003
From: k7rx at comcast.net (Kevin Nathan)
Date: Wed Sep 10 12:13:48 2003
Subject: Topband: Relay Specifications for PT3 Modification
Message-ID:
Hi All,
I am blind and have a friend who is attempting to perform the mod to my
Ameco PT3 for using a separate receive antenna. In the information provided
by Ameco, it talks about needing a relay and gives their part number
CMI-SS-212D. We are having a very difficult time contacting Ameco. Can
anyone on the list provide us with the information as to the specifications
of this relay? Is it something which can be purchased from Radio Shack or
some other vender?
We would certainly appreciate any information you could give us.
Thanks very much and very 73.
Kevin, K7RX :)
From w8ji at contesting.com Wed Sep 10 14:07:00 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Wed Sep 10 21:14:27 2003
Subject: Topband: 160 Beacons?Resource?
References: <000801c377a7$11763870$3834d618@presario>
Message-ID: <000f01c377bd$f40505c0$2f8001d8@akorn.net>
> Any details re the following beacons(?) : 1818.9 3ZCU 0445Z; 3ZDA 1829
0100Z and BHBEE 1831.1 0400Z? Any idea of QTH's or what they are for? Can
someone pass along a good resource for beacon or other 'authorized'
international and domestic signal sources for 160? I've tried most of the
net resources with little luck. Tnx, Don Durk, ka1dwx/4
Don,
Beacons that repeat a "callsign" and then put out a carrier (generally in a
cycle of three repeats) with long pauses between repeats are fishing markers
for buoys either for long lines or illegal drift nets. You won't find
callsign Internet references because they are unlicensed. They are
meaningless for propagation because they get moved around and also run very
low power to small antennas.
If you hear a callsign repeating ( sometimes sending just nonsense code)
without the long pause before repeating it is most likely a harmonic of an
airport NDB (non-directional beacon) below the AM BC band. In this case you
could hear the identifier or a negative of the identifier.
There are some intentional digital signals on 160 from New Zealand, Europe
and Africa. Europe has digital transmitters on about 1851, and N. Africa has
one on 1803.5. The NZ digital signals are on about 1816.5 and 1818.5. The NZ
signals appear to have become much less reliable in predicting signals from
ZL than they were a few years ago.
There is also a Europe CW beacon OK1EV that is almost useless (because it is
low power) up around on 1841 or 1845, I forget where exactly. It is an
annoyance rather than useful for anything.
73 Tom
From ulformat at teleport.com Wed Sep 10 23:12:47 2003
From: ulformat at teleport.com (don nelson)
Date: Thu Sep 11 05:41:08 2003
Subject: Topband: 160 Beacons?Resource?
In-Reply-To: <000f01c377bd$f40505c0$2f8001d8@akorn.net>
Message-ID:
FYI: Not all air beacons are below the AM band (although these aren't in the 160m band either....)
1675 TSL (Beacon) Tsile Tsile Morobe PNG 0.05kW believed to be silent
1690 MH (Beacon) Mount Hagen PNG 0.05kW located in central PNG
1692 KIU (Beacon) Kuinga Western Province PNG 0.05kW located in Northern PNG
1725 GA (Beacon) Goroka Eastern Highlands PNG 0.05kW
1737 KUT (Beacon) Kutubu Southern Highlands PNG 0.05kW carrier+USB
Both KUT and GA have been heard regularly on the beverages down at Grayland, Washington. KIU and MH have also been heard by myself
but not recently. All have CW id....
Don
AC7ZG
-----Original Message-----
From: topband-bounces@contesting.com
[mailto:topband-bounces@contesting.com]On Behalf Of Tom Rauch
Sent: Wednesday, September 10, 2003 10:07 AM
To: Don Durk, ka1dwx; topband@contesting.com
Subject: Re: Topband: 160 Beacons?Resource?
> Any details re the following beacons(?) : 1818.9 3ZCU 0445Z; 3ZDA 1829
0100Z and BHBEE 1831.1 0400Z? Any idea of QTH's or what they are for? Can
someone pass along a good resource for beacon or other 'authorized'
international and domestic signal sources for 160? I've tried most of the
net resources with little luck. Tnx, Don Durk, ka1dwx/4
Don,
Beacons that repeat a "callsign" and then put out a carrier (generally in a
cycle of three repeats) with long pauses between repeats are fishing markers
for buoys either for long lines or illegal drift nets. You won't find
callsign Internet references because they are unlicensed. They are
meaningless for propagation because they get moved around and also run very
low power to small antennas.
If you hear a callsign repeating ( sometimes sending just nonsense code)
without the long pause before repeating it is most likely a harmonic of an
airport NDB (non-directional beacon) below the AM BC band. In this case you
could hear the identifier or a negative of the identifier.
There are some intentional digital signals on 160 from New Zealand, Europe
and Africa. Europe has digital transmitters on about 1851, and N. Africa has
one on 1803.5. The NZ digital signals are on about 1816.5 and 1818.5. The NZ
signals appear to have become much less reliable in predicting signals from
ZL than they were a few years ago.
There is also a Europe CW beacon OK1EV that is almost useless (because it is
low power) up around on 1841 or 1845, I forget where exactly. It is an
annoyance rather than useful for anything.
73 Tom
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From JohnG3PQA at onetel.net.uk Thu Sep 11 09:50:50 2003
From: JohnG3PQA at onetel.net.uk (John Rogers)
Date: Thu Sep 11 05:41:10 2003
Subject: Topband: Topband Beacons - W1AW re:160 Beacons?Resource?
Message-ID: <001801c37839$8eb06620$37584ed5@john2>
Thanks to Tom for info. on worldwide beacons.
In recent years with poor condx and less audible USA evening activity, W1AW
has become very useful for predicting the NA east coast path.
On many occasions I have listened half asleep on a dead band thinking condx
were poor again only to hear W1AW pop up at the scheduled time. When the
band is open to USA (eg yesterday) it can peak quite strong - up to s8 or 9.
Pity it uses 1818 exactly because that is the second harmonic frequency of
BBC Radio 5 on 909 from multiple UK locations which for whatever reason is
always s3 or stronger so cannot always read the code Q5.
As the bands lose their commercial stations we will have to rely more on our
own generated beacons, or people putting out the occasional CQ on a
seemingly dead band.
OK0EV has moved from 1845 up the band (1855 kHz ?) and does not seem to be
active all the time.
To OK stations on the reflector - can someone please advise the new
frequency,
station details and schedule of this beacon. It used to run 100W to a big
vertical so should be audible in USA and other continents when condx are
open.
Does anyone else know of more commercial or broadcast stations (close to
160) in other continents useful as beacons?
73's, John G3PQA
From K1ZM at aol.com Thu Sep 11 07:49:28 2003
From: K1ZM at aol.com (K1ZM@aol.com)
Date: Thu Sep 11 07:50:26 2003
Subject: Topband: Critters Eating Coax
Message-ID: <1d8.10a2cb45.2c91ad38@aol.com>
Thanks to all those who took the time to provide assistance.
My assessment of possible solutions would seem to be these:
1) Best - use 50 ohm hardline - (a bit pricey - but AA1K and others say it
worked for them - Tks Jon)
2) Put the coax in something - like conduit. I see Home Depot has 1/2 inch
PVC conduit available here in NY for 98cents a 10 foot interlocking section
(I will probably go this route).
3) Use flooded - direct burial cable - from the wireman or from RADIOWARE
(Davis RF bury flex)
(I like this one too but I think my red squirrels will still eat this stuff
enough to put me off the air in time - perhaps it would take LONGER - but I
think it would fail eventually.)
4) Bury the coax - tough to do in a DENSE forest - unless you cut all the
trees FIRST which I am loathe to do
So, I will probably go the PVC conduit route - it is EASY to pass RG213
through it as long as the PL259's are off the cable and the various sections can
either be taped or PVC glued together - very EASY to make this one work - just
takes time.
I especially enjoyed the comments like:
1) Rent CATS to scare off the squirrels
2) Get a shotgun - and the cook up the squirrels as ROAD-KILL with onions and
peppers
3) Use salt and birdseed so the squirrels would like that BETTEr THAN THE
JACKET on 213!!
All good ideas - in the end, what works for YOU is the best solution.
I think I am gonna try the Home Depot PVC 1/2 inch conduit.
Tks again to all those who provided ideas. I am most grateful for the help.
73 JEFF
K1ZM@aol.com
From herbs at vitelcom.net Thu Sep 11 11:49:29 2003
From: herbs at vitelcom.net (Herb Schoenbohm)
Date: Thu Sep 11 18:37:56 2003
Subject: Topband: Topband Beacons - W1AW re:160 Beacons?Resource?
In-Reply-To: <001801c37839$8eb06620$37584ed5@john2>
References: <001801c37839$8eb06620$37584ed5@john2>
Message-ID: <3F607D69.6000109@vitelcom.net>
John,
On St. Croix there is WDHP on 1620 Khz which is licensed to run 1 KW
during hours of darkness. They use a 180 foot series feed tower. Please
send me an E mail if you hear them.
73
Herb, KV4FZ
John Rogers wrote:
>
>
>Does anyone else know of more commercial or broadcast stations (close to
>160) in other continents useful as beacons?
>
>73's, John G3PQA
>
>
>
>
>
From keithj at dsl.pipex.com Thu Sep 11 16:46:15 2003
From: keithj at dsl.pipex.com (Keith Jillings)
Date: Thu Sep 11 18:37:57 2003
Subject: Topband: Critters Eating Coax
In-Reply-To: <1d8.10a2cb45.2c91ad38@aol.com>
References: <1d8.10a2cb45.2c91ad38@aol.com>
Message-ID: <3F608AB7.1000102@dsl.pipex.com>
K1ZM@aol.com wrote:
> So, I will probably go the PVC conduit route - it is EASY to pass RG213
> through it as long as the PL259's are off the cable and the various sections can
> either be taped or PVC glued together - very EASY to make this one work - just
> takes time.
If the PVC conduit is the same type as is sold here, you can buy "collars" that
are a push-fit to join sections, with a central flange to hold the conduit in
position. There are also right-angle bends, inspection elbows, and all sorts.
A few drops of superglue, and it's all solid.
I had similar problems with the squirrels here. The solution was the 12-bore
shotgun. Unfortunately, that didn't deal with the mice, who were much more
elusive but did more damage. The cat solved that one.
One I rather fancied trying was to treat the inside of the conduit with Nitrogen
Triiodide (NI3). Avoids repeat attacks by any individual critter.
Keith
--
Keith Jillings
G3OIT GW3OIT G-UTSY at EGMC
From binghamstehekin at starband.net Thu Sep 11 10:40:57 2003
From: binghamstehekin at starband.net (Dick and Adele Bingham)
Date: Thu Sep 11 18:37:58 2003
Subject: Topband: Chewing Critters
Message-ID: <006101c37883$8579b260$1a573f94@Dick>
Greetings everyone
The direct-burial coax and other forms of jacketed hardline can often be obtained as "reel-ends" from your local CATV system. Find out who is responsible for their storage yard and see if they can give you some either for free or the Aluminum scrap-value.
In the past, I have obtained sections up to several hundred feet AND free EHS strand-cable used to support overhead coax. Short pieces are usually a bother to them especially the coax.
BTW, it is easy to make connectors for the ends of the hardline. Use the connectors the CATV folks use (the ones with the outside threaded-ends and the long center-conductor) and do the following:
- Unscrew the outside threaded shell from a Male PL-259 connector and then carefully cut off the portion w/o threads.
- Screw this shell onto the threads of the CATV connector
- Cut the CATV connector's center-pin length appropriate to engage a type-N Female barrel connector when screwed into
the PL-259 sleeve.
- Tape to seal.
Dick - w7wkr CN98pi
Stehekin, WA
From tree at kkn.net Thu Sep 11 14:03:21 2003
From: tree at kkn.net (Tree)
Date: Thu Sep 11 18:37:59 2003
Subject: Topband: TBDC plaques
Message-ID: <20030911180321.GD7338@kkn.net>
Is there anyone who entered the Stew Perry contest last December who feels
they meet either one of the two criteria:
1. Using pre 1960 equipment.
2. Under the age of 21 with at least 50 QSOs?
Thanks.
Tree N6TR
tree@kkn.net
From michael.oexner at web.de Thu Sep 11 22:34:03 2003
From: michael.oexner at web.de (Michael Oexner)
Date: Thu Sep 11 18:38:02 2003
Subject: Topband: 160 Beacons?Resource?
In-Reply-To:
References:
Message-ID: <465890048.20030911213403@web.de>
Hi all,
Below is an extract of my NDB database that I use to produce the
NANDBH and ENDBH.
Cf.
http://members.aol.com/lwcanews/oexnerNDB.htm
or
http://www.beaconworld.org.uk/datafile.htm
Call,kHz,Hz,Station,ITU,Lat,Long
BJO,1600.0,,Bermejo,BOL,S22 45 57,W064 18 39
NHG,1600.0,,Palmer Station,ATA,S64 46 28,W064 04 10
LGM,1602.0,,Leguizamo,CLM,S00 11 00,W074 48 00
TDA,1610.0,,Trinidad,CLM,N05 26 00,W071 39 03
MIL,1615.0,,Quincemil,PRU,S13 14 00,W070 44 00
NZ,1615.0,1020,Nadzab,PNG,S06 34 00,E146 42 45
YPT,1618.0,1020,Ipatinga/Santana do Paraiso/Usiminas,B,S19 27 47,W042 28 46
CEP,1620.0,,Concepcion,BOL,S16 08 06,W062 01 36
ZZ,1620.0,1020,Petrobras XIV,B,S26 46 22,W046 47 02
FAM,1623.0,,Faz Amalia,B,S21 26 36,W047 22 12
GNY,1623.0,1020,Gurney/Alotau,PNG,S10 18 57,E150 21 42
HUM,1623.0,,Humait?,B,S07 32 00,W063 02 00
PP,1623.0,,Porto Trombetas,B,S01 29 30,W056 23 54
PAT,1625.0,1020,Pastaza/Rio Amazonas,EQA,S01 31 00,W078 02 30
SAC,1627.0,,Sao Carlos,B,S21 53 00,W047 53 00
TM,1630.0,1020,Taumarunui,NZL,S38 55 18,E175 18 49
OKT,1632.0,1020,Ok Tedi,PNG,S05 24 36,E141 19 07
ORI,1635.0,,Orito,CLM,N00 40 00,W076 49 00
SJV,1640.0,,San Javier,BOL,S16 19 40,W062 36 17
MOR,1642.0,,Moro,PNG,S06 21 46,E143 15 16
GPA,1644.0,,Garoupa,B,S22 22 18,W040 25 08
MLZ,1645.0,400*,Sao Sebastiao/Plataforma Merluza,B,S25 16 01,W045 15 10
YPI,1645.0,,Yaupi,EQA,S02 51 00,W077 53 00
DOL,1650.0,400,UNID,?,,
VK,1650.0,,Velika Kladusa,BIH,N45 10 50,E015 48 30
MZ,1659.0,400,Halul Island,QAT, ,
PNQ,1659.0,1020,Macae/Platform SS-18,B,S22 40 42,W040 36 24
ZA,1661.0,,North Star I,B,S02 52 25,W039 03 45
KUB,1662.0,1020,Kubuna,PNG,S08 41 39,E146 45 14
ZI,1674.0,,Petrobras III,B,S21 35 38,W040 30 12
TSL,1675.0,1020,Tsile Tsile,PNG,S06 50 31,E146 21 16
MH,1689.0,1020,Mount Hagen,PNG,S05 50 16,E144 18 31
CXS,1690.0,1020,Caxias do Sul/Campo dos Bugres,B,S29 08 38,W051 14 03
KIU,1692.0,1020,Kiunga,PNG,S06 07 18,E141 17 14
CRJ,1700.0,1310,Carajas/Parauapebas/Maraba,B,S06 06 41,W050 00 14
KN,1720.0,,Kandahar,AFG,N31 30 25,E065 51 07
GA,1725.0,,Goroka,PNG,S06 04 40,E145 23 23
FRA,1730.0,1020,Juiz de Fora,B,S21 46 04,W043 23 01
XPC,1734.0,1020,Chapeco,B,S27 07 51,W052 38 58
KUT,1737.0,,Kutubu/Kumul,PNG,S06 20 00,E143 18 00
--
vy 73 + gd DX,
Michael mailto:michael.oexner@web.de
From jbattin at msn.com Fri Sep 12 18:35:08 2003
From: jbattin at msn.com (jbattin)
Date: Fri Sep 12 21:15:11 2003
Subject: Topband: Beverage measurements
Message-ID: <003001c3797e$1f94ee00$dcec6dd1@c0j7r1>
I have posted some results from measurements made this summer on vertical vs
sloping feeds at:
http://nidxa.org/memberWWW/k9dx_home.htm
John K9DX
From sire at iinet.net.au Sat Sep 13 19:35:03 2003
From: sire at iinet.net.au (Steve Ireland)
Date: Sat Sep 13 07:12:36 2003
Subject: Topband: Old British 160m transmitter
Message-ID: <3.0.5.32.20030913183503.00aba800@mail.iinet.net.au>
G'day all
This is a kind of 'shot in the dark'.
I would really like to get my hands on a British 160m AM/CW transmitter
from the 1960s as a restoration project - a KW One-Sixty, a Labgear 160
Twin, or a Minimitter Top Two to Seven (or similar).
If some of the old G3 and G4 topbanders on the reflector have any ideas
where I might lay my hands on something like this, I would VERY much
appreciate knowing. My idea is that I will visit my Dad in the UK sometime
in the next six months and would like to take one of the above home in the
luggage.
Vy 73,
Steve, VK6VZ (ex- G3ZZD)
From w2up at mindspring.com Sat Sep 13 16:13:59 2003
From: w2up at mindspring.com (Barry )
Date: Sat Sep 13 11:53:26 2003
Subject: Topband: Low band receiving loop
Message-ID: <3F633437.22185.F920EA@localhost>
Hi all,
I just put the finishing touches on a web page (my first attempt, so
be kind, hi) documenting construction of a rotatable receiving loop
for the low bands. I'll be updating it in the winter, after doing
some A/B comparisons with a seasonal 600 ft Beverage to EU (to be put
back up in November). Feel free to link to it, if you wish.
http://w2up.home.mindspring.com/160-loop/loopt.htm
73,
Barry W2UP--
Barry Kutner, W2UP Internet: w2up@mindspring.com
Newtown, PA Frankford Radio Club
From richard at karlquist.com Sat Sep 13 10:13:59 2003
From: richard at karlquist.com (Richard Karlquist)
Date: Sat Sep 13 12:27:02 2003
Subject: Topband: Beverage measurements
In-Reply-To: <003001c3797e$1f94ee00$dcec6dd1@c0j7r1>
Message-ID:
That's very interesting. I think you have now
permanently debunked the sloping wire configuration,
in case anyone still believed in it. It wasn't clear
if you also eliminated the vertical drop
from the terminated end as well. That should
also matter, although its effects are
reduced by the attenuation of the propagation
along the length of the wire, which could easily
be 3 to 6 dB.
I am also wondering if the shorter vertical drop
explains why I get better results with low beverages
(2 ft) rather than high ones (10 ft).
What height was the beverage in the test?
I agree with your comment about narrowing the front
lobe; I think this is why the concensus seems to be
to go with broadside arrays of beverages instead of
extremely long individual ones.
Rick N6RK
> I have posted some results from measurements made this summer on
> vertical vs
> sloping feeds at:
>
> http://nidxa.org/memberWWW/k9dx_home.htm
>
> John K9DX
From W8UVZ at voyager.net Sun Sep 14 10:23:18 2003
From: W8UVZ at voyager.net (George Taft)
Date: Sun Sep 14 19:38:36 2003
Subject: Topband: JD1YBJ
Message-ID: <3F646BC6.A44FE4AA@voyager.net>
We see spotting of the activity on 160 Mfrom this club station on Marcus
Is (MT) and many, many of us would like to work this one on top band.
Can someone in Asia provide some details as to the operator, length of
stay?
Today, the station was apparently operating very near 1820 but no copy
in midwest NA. Copy might have been possible except for the BC station
harmonics/mixing that occurs every 5 Khz (1820, 1825, 1830 etc) in NA
that make these frequencies almost impossible to use.
I did hear N7JW calling on 1819.9 and apparently work this station but
solid S9 carrier on 1820 that takes midwest and eastern NA out of the
possibility of any QSO. Some assistance in helping this very rare stn
choose another freq would be very much appreciated?
73 George W8UVZ
From salfar at tin.it Sun Sep 14 18:52:57 2003
From: salfar at tin.it (salfar@tin.it)
Date: Sun Sep 14 19:38:38 2003
Subject: Topband: 80 m. antenna mast to use on 160 m. also
Message-ID: <3F58E5CA00005847@ims4d.cp.tin.it>
Hi,
preparing setup for next cqww from Crete
(as J49Z), we're looking for some easy and
fast solution to use our 19,20 m. mast (63 ft.) that works
perfectly on 75 m. band, also on 160 m.,
may be inverted L or T loaded may work.
Any suggestion about cable lenght of the systems
of course we have to keep 75 meters working ok also.
Our Crete qth is on the beach and some radials
will be "swimming" into Mediterranian sea.
Any help is appreciate but consider us "real beginners"
Thanks, 73s
Salv, IK8UND
Lou, IK8HCG
on behalf of j49z
www.qsl.net/i2wij/j49z/j49z.html
From jlome at plasticosomega.com Sun Sep 14 14:49:26 2003
From: jlome at plasticosomega.com (Javier Lopez)
Date: Sun Sep 14 19:38:39 2003
Subject: Topband: Performance of the FT-847 for LB?
Message-ID:
Hi,
I would like to know if there is someone on this list that had have
experiences with FT-847 in low bands or HF by itself?
Comments will be appreciatted,
73's de Javier
yv5mbx
From w8ji at contesting.com Sun Sep 14 21:48:45 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Mon Sep 15 13:30:06 2003
Subject: Topband: 160 Beacons
References:
Message-ID: <006401c37b23$20b96a80$3e8001d8@akorn.net>
As a thought....to be useful a beacon really has to run at least a few
hundred watts to a reasonable antenna. It needs to be reasonably comparable
to average stations, otherwise DX stations can't really use it to monitor
conditions.
The OK1EV beacon, for example, is largely useless here. The only time I hear
it is when all the Europeans are just booming in. If the band isn't totally
wide open even for weak signals, I can't hear it. That makes it useless over
here.
160 and other low bands really need a worldwide system of timed beacons with
reasonable antennas and power. I think low bands need this far more than 20
meters does!
73 Tom
From tree at kkn.net Mon Sep 15 16:31:27 2003
From: tree at kkn.net (Tree)
Date: Mon Sep 15 16:20:31 2003
Subject: Topband: Stew Perry Topband Distance Challenge Results
Message-ID: <20030915203127.GA23238@kkn.net>
The results of the 7th running of the Stew Perry Top Band Distance
Challenge have just been published on the web.
http://web.jzap.com/k7rat/stew.html
The eighth running will be on December 27th/28th. Hope you can join
the fun.
73 Tree N6TR
tree@kkn.net
From btippett at alum.mit.edu Mon Sep 15 22:48:56 2003
From: btippett at alum.mit.edu (Bill Tippett)
Date: Mon Sep 15 21:51:46 2003
Subject: Topband: Beverage measurements
Message-ID: <6.0.0.22.0.20030915214134.03406e40@pop.vnet.net>
Hi John!
K9DX wrote:
>7. If you want better signal to noise, reduce the beam-width. Going from
15 to 30db off the sides or back, won't do much.
Do you feel this applies to staggered/phased Beverages
(i.e.echelon)? My greatest noise problem is often thunderstorms
from the South-Central US when trying to listen toward Europe.
I've been considering staggered/phased Beverages as a solution
and believe this should help greatly. Even if individual Beverage
F/R patterns are not great, the result of a phased/staggered pair
should work fairly well IMHO. Any thoughts on this?
73, Bill W4ZV
From richard at karlquist.com Mon Sep 15 20:54:39 2003
From: richard at karlquist.com (Richard Karlquist)
Date: Tue Sep 16 05:33:00 2003
Subject: Topband: 160 Beacons
In-Reply-To: <006401c37b23$20b96a80$3e8001d8@akorn.net>
Message-ID:
> 160 and other low bands really need a worldwide system of timed
> beacons with
> reasonable antennas and power. I think low bands need this far
> more than 20
> meters does!
>
> 73 Tom
What is the legality of a 160 meter beacon for FCC licensees?
I searched on this a little and it seems that "unattended"
ones are only allowed on 10 meters and up and then only in
specific subbands. I vaguely remember someone telling me
the NCDXF ones on 20 through 12 meters had to get
special permission or something. I tried to get them
interested in low band beacons and they basically said
"forget about it". What is an "attended" beacon anyway?
Sounds like you might just as well call CQ if you have
to be there.
Of course, for a world wide system, other govt's have to
give permission under their own rules.
Rick N6RK
From jbattin at msn.com Tue Sep 16 06:27:23 2003
From: jbattin at msn.com (jbattin)
Date: Tue Sep 16 07:07:09 2003
Subject: Topband: Beverage measurements
Message-ID: <004101c37c3d$1f086900$2ad523c7@c0j7r1>
----- Original Message -----
From: "jbattin"
To: "Bill Tippett"
Sent: Monday, September 15, 2003 9:41 PM
Subject: Re: Topband: Beverage measurements
I think one of things a stagger does is to not only phase the beverages
but
phase the vertical feeds to also null their pick-up in a given direction. I
think JI phases some of his beverages to get rid of Florida QRN. My
comments
on S/N ratio speaks to omni directional noise. It doesn't really take a
computer to get a feel of what is going on. If the forward lobe is 36
degrees, a 10x (or 10db) front to side/rear ratio will yield about equal
noise from the front lobe and the rest of the directions. If you have 16 db
front to side/rear ... then the front lobe noise will dominate the other
noise by 6 db.
My 9 element array has 30 - 40 db rejection off the side and rear. There
are a few times ..... and few is the word... that it makes a practical
improvement on QRN ... it often makes an terribly unusable band just
unusable. In your case, where there is a consistent direction for the noise
and the noise is of such a level that a 20 db. improvement will make the
band functional, it sounds promising. These issues are not a matter of few
db. one way or the other. It takes tens of db's to get something you can
hear.
John
----- Original Message -----
> From: "Bill Tippett"
> To: ;
> Sent: Monday, September 15, 2003 8:48 PM
> Subject: Re: Topband: Beverage measurements
>
>
> > Hi John!
> >
> > K9DX wrote:
> > >7. If you want better signal to noise, reduce the beam-width. Going
from
> > 15 to 30db off the sides or back, won't do much.
> >
> > Do you feel this applies to staggered/phased Beverages
> > (i.e.echelon)? My greatest noise problem is often thunderstorms
> > from the South-Central US when trying to listen toward Europe.
> > I've been considering staggered/phased Beverages as a solution
> > and believe this should help greatly. Even if individual Beverage
> > F/R patterns are not great, the result of a phased/staggered pair
> > should work fairly well IMHO. Any thoughts on this?
> >
> > 73, Bill W4ZV
> >
> > _______________________________________________
> > Topband mailing list
> > Topband@contesting.com
> > http://lists.contesting.com/mailman/listinfo/topband
>
From w8ji at contesting.com Tue Sep 16 07:53:39 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Tue Sep 16 07:07:12 2003
Subject: Topband: Beverage measurements
References: <6.0.0.22.0.20030915214134.03406e40@pop.vnet.net>
Message-ID: <000901c37c40$caddf1c0$188001d8@akorn.net>
> (i.e.echelon)? My greatest noise problem is often thunderstorms
> from the South-Central US when trying to listen toward Europe.
A deep null is necessary only if there is a very strong noise in the null
area.
I find the Echelon arrangement not especially helpful because there is
little QRN at ~235 degrees.
Instead, I pick a element length and spacing that has very deep nulls
towards Florida. When I watch the lightning maps, most frequently storms
are over Florida. The closer Florida storms are also very much louder here
than anything from Central America, plus it helps reduce QRM from a SSB net.
73 Tom
From w8ji at contesting.com Tue Sep 16 08:24:35 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Tue Sep 16 10:42:12 2003
Subject: Topband: 160 Beacons
References:
Message-ID: <001101c37c45$1d059a80$188001d8@akorn.net>
It would have to be an attended beacon.
I didn't (and still don't) like the idea of unattended QRP beacons, because
they are generally useless to anyone interested in propagation. The higher
power is why stations like DHJ were so useful. I remember leaving my
receivers on DHJ for hours, watching for band openings.
Higher power unattended or attended beacons could be quite useful, if
regulated and coordinated with known power and antennas.
I have the antenna spacing to run maybe 250-1000 watts and not bother my own
receivers. I've been thinking about something on 1999, but I wonder if
propagation is better up there and it might not reflect on what is happening
on the 1800 end??
> interested in low band beacons and they basically said
> "forget about it". What is an "attended" beacon anyway?
> Sounds like you might just as well call CQ if you have
> to be there.
The problem with CQ's is they are usually in the prime activity area of the
band, taking up room when the CQ'er might not have propagation. They also
are on random frequencies, no one knows where to look. Searching from 1815
to 1840 for weak signals is like looking for a needle in a haystack.
What I was thinking of is this. Some of us could buy MFJ Beacon clocks
(assuming they work OK) that are synchronized to WWVL. By stealing voltage
of the red LED's, we could have accurately timed signals to trigger a memory
keyer, and that could key the radio.
We could put several beacons on one frequency doing this.
We also need to establish some sort of International calling frequencies,
like six meters has, where calls are made but people vacate. That would help
a great deal.
73 Tom
From JohnG3PQA at onetel.net.uk Tue Sep 16 15:36:33 2003
From: JohnG3PQA at onetel.net.uk (John Rogers)
Date: Tue Sep 16 10:42:15 2003
Subject: Topband: 160 Beacons
References:
<006401c37b23$20b96a80$3e8001d8@akorn.net>
Message-ID: <001001c37c57$8c0a7380$c1454ed5@john2>
Nil heard of OK0EV the last few days, anyway.
73's John
> The OK1EV beacon, for example, is largely useless here. The only time I
hear
> it is when all the Europeans are just booming in.
From btippett at alum.mit.edu Tue Sep 16 11:49:24 2003
From: btippett at alum.mit.edu (Bill Tippett)
Date: Tue Sep 16 10:58:45 2003
Subject: Fwd: Re: Topband: Beverage measurements
Message-ID: <6.0.0.22.0.20030916104551.03901a40@pop.vnet.net>
Received the following response from WW2Y...I had
forgotten about the excellent paper he and K2WI did in 1997.
73, Bill W4ZV
> Hi Bill,
> Please read my paper on end fire beverage arrays. The 3 element array
>towards
>europe completely wiped out all QRN and man made noise sources from the sides
>and
>rear. It's a VERY quiet system. Even a 2element version makes a BIG
>improvement in
>directivity.
> http://www.exit109.com/~kz2s/bev_arrays/
>
> 73, Peter
From jon.zaimes at dol.net Tue Sep 16 12:23:24 2003
From: jon.zaimes at dol.net (Jon Zaimes AA1K)
Date: Tue Sep 16 12:15:06 2003
Subject: Topband: Beverage measurements
In-Reply-To: <6.0.0.22.0.20030915214134.03406e40@pop.vnet.net>
Message-ID: <5.2.0.9.0.20030916110655.00aa1540@127.0.0.1>
Hi Bill,
The stagger-phased Beverages are a big advantage here. I can hear things on my European pair that are inaudible on a single wire in the same direction (pair are 513-feet long; single about the same).
A stagger pair at 324 degrees, each 465-feet long, seem to do about as well as the single-wire 880-foot wire in same direction.
New parallel phased pair due West -- 525 feet each, spaced 312 feet -- is also a big improvement over single wire.
A parallel pair of 950-foot wires toward JA, spaced 175 feet, offered some improvement over a single 500-foot wire in the same direction, in the few tests I was able to make on it last season. But I will probably be converting it to a stagger-phased pair soon.
The stagger pair of course doesn't narrow the beamwidth, just improve the f/b, with a deeper null to the rear of the rearward element (with the leading current). The broadside (parallel) pair spaced 300+ feet gives a narrower lobe and improved f/b. Either one could be an advantage, depending on your target area and orientation of the nulls.
Next step here is to add a second stagger phased pair toward Europe, spaced 400 feet away, and feed the two pairs together for additional improvement.
73/Jon AA1K
My new At 09:48 PM 9/15/03, you wrote:
>Hi John!
>
>K9DX wrote:
>>7. If you want better signal to noise, reduce the beam-width. Going from 15 to 30db off the sides or back, won't do much.
>
> Do you feel this applies to staggered/phased Beverages
>(i.e.echelon)? My greatest noise problem is often thunderstorms
>from the South-Central US when trying to listen toward Europe.
>I've been considering staggered/phased Beverages as a solution
>and believe this should help greatly. Even if individual Beverage
>F/R patterns are not great, the result of a phased/staggered pair
>should work fairly well IMHO. Any thoughts on this?
>
> 73, Bill W4ZV
>
>_______________________________________________
>Topband mailing list
>Topband@contesting.com
>http://lists.contesting.com/mailman/listinfo/topband
From Bill at AA6TT.com Tue Sep 16 14:16:35 2003
From: Bill at AA6TT.com (William H. Hein)
Date: Tue Sep 16 14:14:22 2003
Subject: Topband: 3-element Beverage array
Message-ID: <014901c37c76$4d7d2c60$d401a8c0@TOSHIBALAPTOP>
WW2Y's 3-element Beverage array sounds interesting--how does one feed it?
I just finished adding radials and tuning my 160m 4-Square (Jay WX0B and
Paul N5RT were in the neighborhood to help), I went from 2elevated
1/8th-wave radials to 8 elevated 1/8th-wave radials on each vertical and
tweaked the phase controller, seems to be a significant improvement but I
haven't yet had decent band conditions to really test it. I still hope to
install a ground screen under the array before the ground freezes.
73,
Bill NT1Y (ex-AA6TT)
From kl7ra at ptialaska.net Tue Sep 16 18:51:44 2003
From: kl7ra at ptialaska.net (KL7RA)
Date: Wed Sep 17 06:21:50 2003
Subject: Topband: Making your own Base Insulators
Message-ID: <001501c37cbe$bd443460$aa7997d0@kl7ra>
I'm in the process of moving this station from the arctic to
the Kenai peninsula on a hill top about a mile from the ocean.
Sunday we un-installed the Rohn 25 1/4 wave topband vert
with insulated base using the Rohn BPH25G tiltover base and
a sheet of Teflon.
After about eight years the Teflon looked fine, a little dirty
but still a good insulator and intact. I had the base covered
with a tarp and never had a failure at full smoke, summer or
winter. Mostly winter and snow however.
The top plate is spun around 180 degrees and is bolted to
the bottom plate with the Teflon in between. Four half inch
bolts are used with Teflon spacers and washers to make it
as secure as the original design.
The sheet Teflon is 1/4 inch. The spacers were cut from one
inch bar stock with a half inch hole. The sheet was cut to fit
the top plate and the end pieces were used as the washers.
I had some interest in this from my previous post and took
two pictures. The first shows the base plate in its normal
configuration with the Teflon parts. The second is the base
plate insulated. I don't have a web site but would be happy
to forward these pics to anyone.
Using the Rohn BPH25G with a sheet of Teflon to insulate
the base of a tower is probably only a good idea if you can
find one used or cheap.
73 Rich KL7RA
From w8ji at contesting.com Wed Sep 17 06:52:05 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Wed Sep 17 06:21:52 2003
Subject: Topband: Beverage phasing
References: <6.0.0.22.0.20030916104551.03901a40@pop.vnet.net>
Message-ID: <002101c37d01$5e185c80$178001d8@akorn.net>
There is no reason this has to be a single band system. I'd get rid of the
90 degree lumped component feed, and use the system on my Web pages. It is
very rare when the 90 degree Hybrid is a better solution. If you get rid of
that, then the stagger can be ANY amount less than 90 degrees and the F/B
will be excellent. Certainly the antenna would be usable over at least a 3:1
frequency range.
My Echelon Beverages and Broadside Beverages operate over very wide
bandwidths using crossfire phasing, and it actually is easier to build!!
They work as well on 80 as on 160, and are still quite usable on 40m and the
BC band and lower.
> >rear. It's a VERY quiet system. Even a 2element version makes a BIG
> >improvement in
> >directivity.
> > http://www.exit109.com/~kz2s/bev_arrays/
73 Tom
From tod at skypoint.com Thu Sep 18 01:51:18 2003
From: tod at skypoint.com (Tod - Idaho)
Date: Thu Sep 18 06:32:00 2003
Subject: Topband: 160 Beacons
In-Reply-To: <001101c37c45$1d059a80$188001d8@akorn.net>
Message-ID:
Clearly, Tom's idea of time coordinated calling/transmissions could be put
together without worrying about anything as long as the stations were
attended. To put together something that involves 'unattended' and/or
attended may be a little harder and might benefit from IARU participation.
It comes to mind that most folks would want to 'operate' rather than
'beacon' when conditions are good or some prime DX comes on the air. That
sort of conflicts with the coordinated attended beacons doesn't it?
Tod, K?TO
-----Original Message-----
From: topband-bounces@contesting.com
[mailto:topband-bounces@contesting.com]On Behalf Of Tom Rauch
Sent: Tuesday, September 16, 2003 6:25 AM
To: Richard Karlquist; Topband@Contesting. Com
Subject: Re: Topband: 160 Beacons
It would have to be an attended beacon.
I didn't (and still don't) like the idea of unattended QRP beacons, because
they are generally useless to anyone interested in propagation. The higher
power is why stations like DHJ were so useful. I remember leaving my
receivers on DHJ for hours, watching for band openings.
Higher power unattended or attended beacons could be quite useful, if
regulated and coordinated with known power and antennas.
I have the antenna spacing to run maybe 250-1000 watts and not bother my own
receivers. I've been thinking about something on 1999, but I wonder if
propagation is better up there and it might not reflect on what is happening
on the 1800 end??
> interested in low band beacons and they basically said
> "forget about it". What is an "attended" beacon anyway?
> Sounds like you might just as well call CQ if you have
> to be there.
The problem with CQ's is they are usually in the prime activity area of the
band, taking up room when the CQ'er might not have propagation. They also
are on random frequencies, no one knows where to look. Searching from 1815
to 1840 for weak signals is like looking for a needle in a haystack.
What I was thinking of is this. Some of us could buy MFJ Beacon clocks
(assuming they work OK) that are synchronized to WWVL. By stealing voltage
of the red LED's, we could have accurately timed signals to trigger a memory
keyer, and that could key the radio.
We could put several beacons on one frequency doing this.
We also need to establish some sort of International calling frequencies,
like six meters has, where calls are made but people vacate. That would help
a great deal.
73 Tom
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From ken.d.brown at verizon.net Thu Sep 18 19:17:25 2003
From: ken.d.brown at verizon.net (Ken Brown)
Date: Fri Sep 19 06:16:23 2003
Subject: Topband: 160 Beacons
References:
Message-ID: <3F6A8355.2090404@verizon.net>
What if the ON/OFF function of each beacon were controllable over the
internet by beacon operation society members around the world with
passwords. As long as one member was logged into the system, would it
then be "attended"?
From on4kj at skynet.be Fri Sep 19 17:19:04 2003
From: on4kj at skynet.be (on4kj)
Date: Fri Sep 19 11:45:33 2003
Subject: Topband: 160 Beacons
References:
<3F6A8355.2090404@verizon.net>
Message-ID: <005301c37eb8$fae06cc0$f170c950@hermansjos>
And why not having a cluster who collects data from fixed beacon receivers.
So we have a complete overview of propagation conditions continually in
chart, at any time all over the world ...........
jos on4kj
ps: Jos is not actif (yet ) on topband because of not ebnough space for
antenna.
Can't persue myself to charge the 65 foot tower at 20 foot from the chack.
affraid for RF return in the schack, at this short distance .
----- Original Message -----
From: "Ken Brown"
To: "Tod - Idaho" ; "topband"
Sent: Friday, September 19, 2003 6:17 AM
Subject: Re: Topband: 160 Beacons
> What if the ON/OFF function of each beacon were controllable over the
> internet by beacon operation society members around the world with
> passwords. As long as one member was logged into the system, would it
> then be "attended"?
>
>
>
> _______________________________________________
> Topband mailing list
> Topband@contesting.com
> http://lists.contesting.com/mailman/listinfo/topband
>
>
From wb6rse at earthlink.net Fri Sep 19 16:47:11 2003
From: wb6rse at earthlink.net (Steve Lawrence)
Date: Sat Sep 20 13:58:43 2003
Subject: Topband: KM9D in YJ
Message-ID: <34B8A7B2-EAF3-11D7-B71A-0003931129C6@earthlink.net>
FYI - Here is the latest from Mike, KM9D. No word on planned bands of
operation.
73, Steve WB6RSE
______________________________________
We are now lying to anchor at Tegua Island in the Torres Island group,
northern Vanuatu. Vanikoro in the Solomon Islands, Santa Cruz group
lies only about 100km north of this position.
73 for now,
de Mike, YJ0AMY
From richard at karlquist.com Sat Sep 20 10:30:30 2003
From: richard at karlquist.com (Richard Karlquist)
Date: Sat Sep 20 13:58:50 2003
Subject: Topband: 160 Beacons
In-Reply-To: <005301c37eb8$fae06cc0$f170c950@hermansjos>
Message-ID:
> And why not having a cluster who collects data from fixed beacon
> receivers.
> So we have a complete overview of propagation conditions continually in
> chart, at any time all over the world ...........
>
> jos on4kj
Another possibility is what I call "reverse beacons":
Set up receivers in various locations to monitor 160
meters and connect them to the internet using a network
such as Echolink or IRLP in receive-only mode. Then
to test propagation, you would send your call and grid
square on the beacon receiver input frequency and see if you can
hear it via your sound card. Kind of like kerchunking
a repeater, or pinging an internet node :-).
Stations could also passively monitor the reverse beacon
and listen for other stations and note their grid squares.
This can provide propagation information. It
is even possible that the beacon could decode CW and
spot successful pings to the DX cluster.
The advantage of this is that it completely sidesteps
the regulatory issue of attended operation and also the
100w power limit. If you're a big gun, you can hit the
beacon with your best shot. It also gets around the problem of
"I'd rather be operating than beaconing".
I can imagine a receiver on the west coast of Europe
connected to several beverages pointed west, to check
for the annual :-) opening to the USA west coast.
Rick N6RK
>
From K1ZM at aol.com Sat Sep 20 07:08:20 2003
From: K1ZM at aol.com (K1ZM@aol.com)
Date: Sat Sep 20 14:30:24 2003
Subject: Topband: Beacons - ARRL W1AW
Message-ID:
Dunno if this is commonly known, but according to the ARRL Letter, W1AW will
be moving down 1/2 kHz to 1817.5. The move is planned to avoid dead-one
birdies from the BC band and elsewhere.
I suppose this will make them easier to copy overseas, assuming 1817.5 is
clear in most parts of the world.
FYI.
73 JEFF
K1ZM@aol.com
From tao at skypoint.com Sat Sep 20 16:05:37 2003
From: tao at skypoint.com (Tod - Idaho)
Date: Sat Sep 20 19:26:01 2003
Subject: Topband: RE: Karlquist Proposal for reverse beacons
In-Reply-To:
Message-ID:
This sounds like a really good idea. It should be much easier to establish
receivers in interesting locations than transmitting stations. One small
matter is access to the internet, but I think that could be handled.
If one does this I would suppose that having a 'standard' transmission that
contained location, time, power, emitting station, etc. would allow multiple
receivers to report multiple emitters in real time as well as logging the
reception in case someone wanted to use the data for some sort of
propagation study. There are a number of special modulation modes (WOLF,
etc.) that allow very weak signals to be detected and received. These are in
regular use by the LOWFER folks -- those are the guys that run 1 watt to
antennas that are 45 feet or less in height.
I think that Rick's idea of using the Internet to tell us 'how we are doing'
at the other end is really interesting. One might suppose that you would not
need to set up special 'beacon receiver sites'. We could start by using our
regular stations when we are not operating just to see if the concept is
feasible. I wonder if someone will be interested enough to become a 'project
manager' for something like this. Without some structure it will be just
another interesting idea.
Tod, K?TO
**************** Message from Rick **************************
Another possibility is what I call "reverse beacons":
Set up receivers in various locations to monitor 160
meters and connect them to the internet using a network
such as Echolink or IRLP in receive-only mode. Then
to test propagation, you would send your call and grid
square on the beacon receiver input frequency and see if you can
hear it via your sound card. Kind of like kerchunking
a repeater, or pinging an internet node :-).
Stations could also passively monitor the reverse beacon
and listen for other stations and note their grid squares.
This can provide propagation information. It
is even possible that the beacon could decode CW and
spot successful pings to the DX cluster.
The advantage of this is that it completely sidesteps
the regulatory issue of attended operation and also the
100w power limit. If you're a big gun, you can hit the
beacon with your best shot. It also gets around the problem of
"I'd rather be operating than beaconing".
I can imagine a receiver on the west coast of Europe
connected to several beverages pointed west, to check
for the annual :-) opening to the USA west coast.
Rick N6RK
From sebdesn at ecentral.com Fri Sep 19 19:31:57 2003
From: sebdesn at ecentral.com (sebdesn)
Date: Sat Sep 20 19:26:03 2003
Subject: Topband: W1AW 160 Freq
Message-ID:
Got this from ARRL today.
Bud Schieving W?HG
ARLB060 W1AW to shift 160-meter transmission frequency
Starting Monday, September 29, W1AW will shift its 160-meter code
practice and bulletin transmission frequency from 1818 kHz to 1817.5
kHz, starting with the 4 PM EDT (2000 UTC) code practice run.
The frequency shift not only brings W1AW's Top Band frequency in
line with those the station uses on other bands, it also should help
to eliminate possible interference from broadcast station harmonics
and birdies--something that's more likely on an integer (ie, whole
number) frequency.
W1AW has been conducting code practice and bulletin transmissions on
1818 kHz since 1982. Prior to that, W1AW transmitted both CW and
phone bulletins on 1835 kHz.
NNNN
/EX
From smlx at earthlink.net Sat Sep 20 18:21:59 2003
From: smlx at earthlink.net (Steve Lawrence)
Date: Sat Sep 20 21:50:01 2003
Subject: Topband: Australs
Message-ID: <9D81FAAA-EBC9-11D7-B117-0003931129C6@earthlink.net>
FYI
FO/DL3GA and FO/DL1IAN are now active from the Australs on 12m. The SSB
station told me that they had NO antenna for 160 but would be on 80m
later. 9-21 0019Z as I write this.
From the DXNL:
AUSTRAL ISLANDS, FO/a, OC-152
Richard,DJ4OI, Andreas,DL3GA, Markus,DL1IAN, and Joachim,DF6IC,
will be
active in SSB/CW/RTTY/digital modes on 80-6m (including WARC bands)
from Tubuai (OC-152) between Sep 18 and Oct 3. They will probably
use
the callsigns FO/homecall/A. QSL via bureau.
73, Steve WB6RSE
From w8ji at contesting.com Sat Sep 20 21:23:38 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Sat Sep 20 21:50:07 2003
Subject: Topband: RE: Karlquist Proposal for reverse beacons
References:
Message-ID: <001b01c37fd6$a4eb0360$3b8001d8@akorn.net>
While the concept of a receiver is interesting, many good locations would
not be able to participate. The best and least expensive internet
connections are in populated areas, right where copy is worse. Another
problem is the receiver would have to be omni, or dedicated to a few
directions.
My general thought was to spur interest and activity in 160 by DX stations.
Nothing is more frustrating than to have a wide open band and no one on.
A "ping-back" would get ONE station on, as he checked the band and decided
it was "dead" (the receiver certainly couldn't be good while omni, and if it
was directional no one would have any idea of the path direction). You'd
have to do a dozen test pings to make up for QSB. If the ping was public
sooner or later a moron or two would figure out sending a rare call locally
would wake up everyone!
A beacon network with **useful ERP** could tell hundreds how the band is,
what direction the path is, and how the fading is. They could leave a
receiver running. Imitating a steady accurately timed beacon would be too
much for most casual pranksters, and the direction would be a giveaway.
I really think we just need four or five medium power beacons spead over the
USA, maybe two in Europe in the east and west with *reasonable power*,
something in north and south South America, and so on.
If the beacons are on 1999kHz, it is easily possible to notch them out of
any receiver. Besides...if the station hosting the beacon was actually
active and working people, the beacon wouldn't be needed.
>From an engineering and usefulness standpoint, the transmitting beacon has
it all over other systems I can think of. At least that's my opinion.
An international calling frequency might be nearly as good, however.
73 Tom
From sire at iinet.net.au Sun Sep 21 10:24:34 2003
From: sire at iinet.net.au (Steve Ireland)
Date: Sat Sep 20 21:50:13 2003
Subject: Topband: Small Tx/Rx antennas with front-to-back and front-to-size
Message-ID: <3.0.5.32.20030921092434.00abd5d0@mail.iinet.net.au>
G'day all
There has been quite a lot written on the reflector recently about the
advantages of having good front-to-back and front-to-side rejection on
Beverages or a phased vertical system - mainly by stations such as W8JI and
K9DX, who have spent long hours building very large antenna systems that
deliver amazing performance in these areas.
Whilst simpler systems such two phased or parasitic delta loops or inverted
Ls cannot offer the front-to-back and front-to-side noise rejection of the
four-element+ phased vertical arrays and staggered Beverages used by these
stations, they do offer do offer substantially improved noise rejection
ability to a single element antenna, as well as a small amount of gain.
Earlier this year I moved from a Marconi-T antenna (with a 20 metre/66'
vertical section) over an eighth wave ground screen (35 x 66' radials) to
two linear loaded (at the voltage ends) three-quarter sized delta loops.
The footprint required by the two vertically polarised antenna systems was
very similar - the delta loop array requiring a bit more land of
approximately 46 metres (~150') by 32 metres (~100') in size.
The (predominantly) vertically polarised delta loop array lies over the
same ground screen as the Marconi-T did and is almost as noisy when either
of its loops are used as single elements. However, phase them together as
a figure-8 array (no f/b but some 15 - 20dB f/s) or as a conventional
parasitic 2-element director/reflector array (even better), then the noise
REALLY drops away.
In my favoured DX direction, the noise levels is typically S7/8 on a single
loop and S1/S2 on the parasitic configuration.
Until I had this simple array, I only a vague idea of where my 'noise'
(atmospheric, domestic electrical) was coming from - and no way of
rejecting any of it, as my semi-rural half acre block is too small to run a
decent Beverage on (except during contests when a neighbour allows me to
run one onto their land).
As an antenna, I found a single vertically polarised delta loop at VK6VZ
can be pretty useless for Rx, as (like its Marconi predecessor) it is just
too noisy. However, couple up another loop to it and I have not only got a
small amount of gain in the main DX direction from here, but lots of noise
rejection in the others (in particular with the cardioid type pattern
offered by the conventional radiator/reflector parasitic configuration).
If you can put up a 2-element loop or inverted-L array, do give it a try -
a half acre block is usually just about enough room. The extra space
needed in comparison to a single element antenna is small, but the benefits
are potentially really large.
Vy 73
Steve, VK6VZ
From ersmar at comcast.net Sat Sep 20 23:29:23 2003
From: ersmar at comcast.net (EUGENE SMAR)
Date: Sun Sep 21 06:41:08 2003
Subject: Topband: 160M Beacon protocol?
Message-ID: <001901c37fe8$2d6a7e80$0200a8c0@nrockv01.md.comcast.net>
Gents:
FWIW: The US Govt (military and civilian) have developed and are using
a technique called ALE (Automatic Link Establishment) for their HF emergency
networks. The radios ping each other on several frequencies in sequence, I
believe, and exchange signal info in a handshaking protocol of some kind.
The purpose of the system is to establish a clear HF channel between two
points with minimal operator intervention.
I know very little about this technique other than what I've described
and that my colleagues in MARS ( volunteer radio operators in the US
military radio auxiliary) have been experimenting with it on HF. This
tells me that the software is available from some public source. If there
is interest among Topband folk in exploring this technique for the 160M
beacon network, I'll make a few inquiries and pass along info to the
reflector.
73 de
Gene Smar AD3F
From W4EF at dellroy.com Sat Sep 20 22:04:52 2003
From: W4EF at dellroy.com (Michael Tope)
Date: Sun Sep 21 06:41:12 2003
Subject: Topband: RE: Karlquist Proposal for reverse beacons
References:
<001b01c37fd6$a4eb0360$3b8001d8@akorn.net>
Message-ID: <03c801c37ff5$853e8d10$0100a8c0@1800XP>
> connections are in populated areas, right where copy is worse. Another
> problem is the receiver would have to be omni, or dedicated to a few
> directions.
>
Not necessarily. You could do a reverse of the NCDXF system whereby
the receiver could utilize directional receive antennas with each direction
in a preassigned time slot. A series of ten one minute slots would be
capable
of supporting up to 36 deg azimuth resolution.
>
> A beacon network with **useful ERP** could tell hundreds how the band is,
> what direction the path is, and how the fading is. They could leave a
> receiver running. Imitating a steady accurately timed beacon would be too
> much for most casual pranksters, and the direction would be a giveaway.
>
Agreed.
Mike, W4EF......................
From sire at iinet.net.au Sun Sep 21 22:26:32 2003
From: sire at iinet.net.au (Steve Ireland)
Date: Sun Sep 21 09:53:09 2003
Subject: Topband: 160m DX calling channel
Message-ID: <3.0.5.32.20030921212632.00abfd70@mail.iinet.net.au>
W8JI said
>An international calling frequency might be nearly as good, however.
>
G'day
With the present 'spotty' conditions which might continue for another year
or two, I think this is a great idea. I am often busy with family chores
in the US sunrise window, but monitor 1824 when I can, as there is usually
some activity around there if the band is open - often from Tom.
Let's find a frequency and give it a go. If we use a similar type of
operation to that used on six metres - i.e. if the propagation is good
enough to attract a pile-up, the 'DX' nominates a new frequency and goes
QSY, it should work OK.
Vy 73
Steve, VK6VZ
From wbeyerjr at cfl.rr.com Sun Sep 21 11:11:29 2003
From: wbeyerjr at cfl.rr.com (William F. Beyer Jr.)
Date: Sun Sep 21 10:15:54 2003
Subject: Topband: San Andres Dxpedition on 160M
Message-ID: <3F6DB191.39C35639@cfl.rr.com>
Hello List:
The San Andres Island Dxpedition with be on 1826.5 in a few weeks.
Dxpedition dates 20-28 Oct.
The Antenna will be a 80/160 Vertical, the one used by ZL7C (Chatham
Is.Dxpedition) last October 2002. Thanks Al/K3VN.
There is a photo of the antenna on the web site, under Photo's list.
Hope to work many stations on the Low Bands.....
See you on 1826.5 CW.....+/- QRN, QRM.
--
*See you in the pileups!
The San Andres Team!
William
HK0/N2WB
Florida Dxpedition Group
San Andres Island Dxpedition 2003
http://www.geocities.com/hk02003/
ARMY Rangers
Lead The Way!
"The only thing necessary for the Triumph of EVIL,
is for GOOD Men to do Nothing"
-- Edmund Burke --
"Unless we stand for something,
we shall fall for anything."
-- Peter Marshall --
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If you are not the addressee indicated in this message, or
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From SteamBoilers at aol.com Sun Sep 21 17:42:04 2003
From: SteamBoilers at aol.com (SteamBoilers@aol.com)
Date: Sun Sep 21 17:39:04 2003
Subject: Topband: 160m DX calling channel
Message-ID: <14a.243fbc7a.2c9f671c@aol.com>
Hello Steve
"Let's find a frequency and give it a go. "
The down side is that on 160 it is a lot easier to generate a signal that can
be heard, but due to space limitations the rx side is lacking. In Europe it
is not uncommon for two stations to be on the same frequency not hearing each
other with long distance station calling both and not being heard. If you call
the Dx station you are in the wrong. ( No win situation)
Still think its worth a try
Regards
Alan Downing
G3ZES
From gjerning at flash.net Sun Sep 21 18:11:26 2003
From: gjerning at flash.net (ARNE GJERNING)
Date: Sun Sep 21 22:13:28 2003
Subject: Topband: 4U1UN QSL news
Message-ID: <003301c38095$afac6860$1c1b4bab@066>
Received a my 4U1UN QSL last week for a 160M QSO I made in Jan 1994. After
hearing many bad reports of QSL problems it seems someone has taken this to
task. THANKYOU VERY MUCH. This could mean QSLs for other bands also
available as was the case of my QSL card. They do not have some logs
however some is better than none.
Envelope had the following return address:
4U1UN
PO Box 3873
Grand Central Station
New York, NY 10163
USA
Hope this info might help others to obtain cards.
73 de Arne N7KA
From ac7a at earthlink.net Sun Sep 21 20:28:05 2003
From: ac7a at earthlink.net (Thomas Kuehl)
Date: Mon Sep 22 06:06:33 2003
Subject: Topband: Preamp shielding
Message-ID: <001501c380b1$27de4270$120110ac@texas6oef4glwm>
Hello,
I am in the process of constructing a K9AY loop antenna and have some
questions about shielding for the preamp. My plans call for using the W7IUV
preamp circuit and locating it at the antenna. It would be more convenient
to place it in the shack, but doing so will slightly degrade the system
noise figure, due to the feedline loss ahead of the preamp. The feedline is
RG-58C/U, about 125 feet in length.
A 7-pole Chebyshev high pass filter will be placed in the circuit, before
the preamp. My question is in regard to the shielding of the preamp. I have
an aluminum Bud box, and a painted steel box by Hammond. Either can be used
for the enclosure. What is the most effective box material from a shielding
standpoint? Does it matter? Or should I just go ahead and place the preamp
in an enclosure inside the shack?
Regards, Thomas - AC7A (Tucson)
From fcresce at comcast.net Mon Sep 22 09:20:43 2003
From: fcresce at comcast.net (Fred Cresce)
Date: Mon Sep 22 08:33:59 2003
Subject: Topband: Pre-Amp Shielding
Message-ID: <004201c38103$f1938dd0$6401a8c0@DJZJV911>
Hi Tom
I'm sure some of the other folks on this reflector would agree that the line loss on your coax run for the K9AY loop is very minimal. I would stick my neck out and say less than a dB. I know that for VHF and above we need the preamp right up there, but not at 160M. We're dealing with more atmospheric noise than anything else.
Fred
From john at ae5x.com Mon Sep 22 09:55:40 2003
From: john at ae5x.com (John Harper)
Date: Mon Sep 22 08:59:18 2003
Subject: Topband: Coax to ladder line question
Message-ID: <000501c38108$d3e2e650$6501a8c0@JOHN>
Good morning,
The remnants of Isabel took down my 10-80m dipole that I'd been feeding with
450-ohm ladder line. Rather than replace it, I'm probably just going to
change the feedline on my 160m semi-inverted V from RG-58 to ladder line
(via a 4:1 balun) and use it on all bands.
My question is this:
The inverted V actually has only one leg that slopes; the other is
horizontal like a dipole. By feeding it with coax, I know which leg is "hot"
and have chosen to have the horizontal section of the antenna as the one to
which the coax center conductor is connected. By going thru a balun and then
to ladder line, will there still be a "hot" and a grounded leg or will
current distibution at the feedpoint now be hot on both ends but opposite in
polarity? What I'm really trying to find out is, does it matter which side
of the ladder line is connected to which side of the dipole/inverted V?
Thanks and 73,
John Harper AE5X
Outdoor QRP & 80-Meter DXing: http://www.ae5x.com
From w8ji at contesting.com Mon Sep 22 10:15:23 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Mon Sep 22 13:45:31 2003
Subject: Topband: Preamp shielding
References: <001501c380b1$27de4270$120110ac@texas6oef4glwm>
Message-ID: <000901c3810b$9eef1d80$328001d8@akorn.net>
> preamp circuit and locating it at the antenna. It would be more convenient
> to place it in the shack, but doing so will slightly degrade the system
> noise figure, due to the feedline loss ahead of the preamp. The feedline
is
> RG-58C/U, about 125 feet in length.
Feedline loss, and with that system noise degradation, should be
immeasurable with the feedline at either end of the line since line loss is
less than .7dB compared to a noise figure that certainly must be well over
5dB for the rest of the system. If you don't have good enough noise figure
with the amp at the house, you won't notice a change moving it to the
antenna. Subtle changes in amplifier design and matching transformer design
would have a much larger effect than 125 feet of transmission line, assuming
you make proper connections.
> A 7-pole Chebyshev high pass filter will be placed in the circuit, before
> the preamp.
Watch the loss there, which mostly relates to inductor Q and component and
design tolerances.
Are you sure you need such a large filter before the amp??
>My question is in regard to the shielding of the preamp. I have
> an aluminum Bud box, and a painted steel box by Hammond. Either can be
used
> for the enclosure. What is the most effective box material from a
shielding
> standpoint? Does it matter?
Shielding, once it is a several skin depths thick, can be any material.
Either box would be the same at HF. It is the connection and length of
"floating" seams and how you bring cables into the box that generally
dominates effectiveness. A good rule is to have less than 2ft of shield seam
length per 5MHz. Shielding channel 2 TV would require seam ground points
less than 2 inches apart, and of course at each corner. You can see by that
unless you are shielding VHF energy, it isn't very critical what you do.
On low frequencies like lower HF, you don't even need a shield with good
board layouts if the amplifier and filter mount over and close to
groundplane or have a groundplane on the PC layout! The exception is if you
mount the amplifier very close to a strong source of noise (like a switching
supply with strong HF harmonics).
73 Tom
From w8ji at contesting.com Mon Sep 22 10:23:43 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Mon Sep 22 13:45:33 2003
Subject: Topband: Coax to ladder line question
References: <000501c38108$d3e2e650$6501a8c0@JOHN>
Message-ID: <001701c3810c$bf7c7060$328001d8@akorn.net>
> polarity? What I'm really trying to find out is, does it matter which side
> of the ladder line is connected to which side of the dipole/inverted V?
John,
That shield sure is a wonderment!
Anytime the current in the antenna terminals is not equal and opposite the
feedline will radiate! Even with coax, the current entering and leaving the
braid equals the current in the center conductor, unless the feedline is
radiating.
So it makes no difference with a balun or a feedline with high common mode
impedance.
73 Tom
From NX4D at comcast.net Mon Sep 22 11:00:44 2003
From: NX4D at comcast.net (Doug Waller)
Date: Mon Sep 22 13:45:38 2003
Subject: Topband: Pre-Amp Shielding
References: <004201c38103$f1938dd0$6401a8c0@DJZJV911>
Message-ID: <00f301c38111$eab16fb0$f39a3b44@youry5sn6dl7l3>
The line loss has little to do with the problem. Its the signals leaking
into the coax thats the killer.
I thought coax was well shielded until I put 40 db of preamp in the shack.
The RG-58 picked up broadcast stations at 20 over, with no antenna connected
to the coax. RF chokes on each end of the coax almost solves the problem,
but my next step is to replace the coax with a double shielded type.
RF chokes that work well at 160m must still choke well in the broadcast band
to kill the noise. FT150A-F toroids with 15 turns of mini-coax makes a fine
choke. I now hear very well with the phased loops with an 18 db
preamp/hi-pass filter at the feedpoint.
73, Doug / NX4D
----- Original Message -----
From: "Fred Cresce"
To: "Top Band Reflector"
Sent: Monday, September 22, 2003 8:20 AM
Subject: Topband: Pre-Amp Shielding
Hi Tom
I'm sure some of the other folks on this reflector would agree that the line
loss on your coax run for the K9AY loop is very minimal. I would stick my
neck out and say less than a dB. I know that for VHF and above we need the
preamp right up there, but not at 160M. We're dealing with more atmospheric
noise than anything else.
Fred
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Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From rmf01 at comcast.net Mon Sep 22 13:01:01 2003
From: rmf01 at comcast.net (rmf01)
Date: Mon Sep 22 13:45:46 2003
Subject: Topband: T loaded vertical
Message-ID: <000e01c38122$b884fbe0$838f3c18@ne2.client2.attbi.com>
Hello everyone,
I'm new to topband. Recently got on with a coaxial L at 55 feet and I'm sure that it's no surprise to all that the performance is mediocre, although I have worked 23 countries.
Thinking about erecting in it's place a T loaded vertical and wonder if you have any suggestions on calculating the dimensions of the T if used with a 55 foot or hopefully a 60 foot radiator. The T would have to be partially strung through tree branches. Is a single wire radiator sufficient?
Finally, any suggestions on a matching? If it comes out at ~20 ohms can I direct feed with the RG213 that is in place and use the tuner in the shack or is it best to construct an L/C circuit at the base?
Tnx,
Rich W1TSP
From k9ay at k9ay.com Mon Sep 22 13:10:59 2003
From: k9ay at k9ay.com (K9AY)
Date: Mon Sep 22 13:45:51 2003
Subject: Topband: Preamp shielding
References: <001501c380b1$27de4270$120110ac@texas6oef4glwm>
Message-ID: <006e01c3812c$80a44820$0b7cfea9@k9ay>
Thomas,
If the coax is buried or lying on the ground, it is probably OK to put the
preamp indoors, since the lossy earth will reduce any noise and signal
pickup on the coax feedline. But if you suspect that the feedline is acting
as an unwanted antenna, it may be useful to put the preamp at the
antenna to boost signals before they enter the feedline.
Note that feedline pickup can also couple energy back into the loop,
which requires a different solution -- proper grounding and common-
mode isolation.
73, Gary
K9AY
> Hello,
>
> I am in the process of constructing a K9AY loop antenna and have some
> questions about shielding for the preamp. My plans call for using the
W7IUV
> preamp circuit and locating it at the antenna. It would be more convenient
> to place it in the shack, but doing so will slightly degrade the system
> noise figure, due to the feedline loss ahead of the preamp. The feedline
is
> RG-58C/U, about 125 feet in length.
>
> A 7-pole Chebyshev high pass filter will be placed in the circuit, before
> the preamp. My question is in regard to the shielding of the preamp. I
have
> an aluminum Bud box, and a painted steel box by Hammond. Either can be
used
> for the enclosure. What is the most effective box material from a
shielding
> standpoint? Does it matter? Or should I just go ahead and place the preamp
> in an enclosure inside the shack?
>
> Regards, Thomas - AC7A (Tucson)
From tao at skypoint.com Mon Sep 22 15:25:33 2003
From: tao at skypoint.com (Tod - Idaho)
Date: Mon Sep 22 15:51:35 2003
Subject: Topband: T loaded vertical
In-Reply-To: <000e01c38122$b884fbe0$838f3c18@ne2.client2.attbi.com>
Message-ID:
The T loaded will perform very similarly to the L loaded vertical in the
vertical component is about the same and the T and L are about the same
length -- one centered and the other offset. Generally, the objective of top
loading is to increase the feed point resistance with the idea of reducing
ground losses or making matching easier.
I have found that using a 55 foot radiator and a 45 foot L will produce
about 12 +/-j ohms at the feed point on 160 meters. That reading includes
resistance attributable to the ground resistance (maybe most of it is ground
resistance, I don't know) ( I am assuming that you have some sort of radial
system at the feed point ).
I have just finished modifying a HyTower to make it continuous from top to
bottom (connected stinger to tower at top of tower) and hung a 45 foot wire
from the top of the stinger toward another tall support (tree). My
measurements with a GenRad 1606A RF Bridge gave R readings on 160 on the
order of 12 ohms. The X readings were negative (as expected). I used a
series inductor to get X=0 ohms at about 1.825 MHz. Then I wound a 1:4 unun
(see Sevick's books) on a ferrite rod. The series inductor goes to the low
impedance input of the 1:4 unun and the output is about 55 ohms. The result
was a very flat VSWR curve across the low end of 160 meters. When I did the
matching with an LC network (or tuner) I had to make adjustments every 15
kHz or less to please the transmitter.
Tod, K?TO
-----Original Message-----
From: topband-bounces@contesting.com
[mailto:topband-bounces@contesting.com]On Behalf Of rmf01
Sent: Monday, September 22, 2003 11:01 AM
To: topband@contesting.com
Subject: Topband: T loaded vertical
Hello everyone,
I'm new to topband. Recently got on with a coaxial L at 55 feet and I'm
sure that it's no surprise to all that the performance is mediocre, although
I have worked 23 countries.
Thinking about erecting in it's place a T loaded vertical and wonder if
you have any suggestions on calculating the dimensions of the T if used with
a 55 foot or hopefully a 60 foot radiator. The T would have to be partially
strung through tree branches. Is a single wire radiator sufficient?
Finally, any suggestions on a matching? If it comes out at ~20 ohms can I
direct feed with the RG213 that is in place and use the tuner in the shack
or is it best to construct an L/C circuit at the base?
Tnx,
Rich W1TSP
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From herbs at vitelcom.net Mon Sep 22 18:19:49 2003
From: herbs at vitelcom.net (Herb Schoenbohm)
Date: Mon Sep 22 16:38:27 2003
Subject: Topband: T loaded vertical
In-Reply-To: <000e01c38122$b884fbe0$838f3c18@ne2.client2.attbi.com>
References: <000e01c38122$b884fbe0$838f3c18@ne2.client2.attbi.com>
Message-ID: <3F6F5965.7080109@vitelcom.net>
Rich, Try to get the current loop to appear at the connection to the
flat top T. This can be done by modeling or in the old days we would
just tape a small 6 volt bulb on a loop at the T. While running just
enough power at night to get the bulb to illuminate, keep pruning the
wire until you get the maximum illumination. When you finally go QRO the
light will burn out and you won't have the neighbors calling 911 because
of the flashing light they see in the sky. This will require raising and
lowering the wire ends at night and if you have a forest of trees may
not be a feasible means of tuning your T to maximum performance. Try to
keep the flat top wires equal in length
If you have a 60 foot vertical drop a 75 foot to 80 foot each side of
the T connection should work well as a starting point if you plan to
tune it in the field. Even a smaller flat top will also work if you are
prepared to deal with the increased reactance and lower feed point
resistance at the base. However it is best to match the feed point with
a simple L network and put down as many radial as possible. I have
found this out to be true, that a well designed T design always beats an
inverted L for a long angle DX path. I believe this is due to the
cancellation of much of the horizontal radiation component .
I hope this information will help you.
73
Herb, KV4FZ
Rich, W1TSP wrote:
> Thinking about erecting in it's place a T loaded vertical and wonder if you have any suggestions on calculating the dimensions of the T if used with a 55 foot or hopefully a 60 foot radiator.
>
> Finally, any suggestions on a matching? If it comes out at ~20 ohms can I direct feed with the RG213 that is in place and use the tuner in the shack or is it best to construct an L/C circuit at the base?
>
>
>
>
>
>
From k6se at juno.com Mon Sep 22 18:04:34 2003
From: k6se at juno.com (Earl W Cunningham)
Date: Mon Sep 22 20:26:43 2003
Subject: Topband: T loaded vertical
Message-ID: <20030922.170728.-1862457.0.k6se@juno.com>
Herb, KV4FZ wrote:
"Try to get the current loop to appear at the connection to the flat top
T. This can be done by modeling or in the old days we would just tape a
small 6 volt bulb on a loop at the T."
==========
The highest current point on any antenna is always 1/4 wave from its open
end, regardless of how long the vertical section is. In the case of an
L, this means the horizontal portion would have to be about 130 feet long
to achieve maximum current at the bend in the L.
If the top portion is a T, make sure each of the two sides are equal and
are each about 130 feet long.
73, de Earl, K6SE
From w8ji at contesting.com Mon Sep 22 22:04:33 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Tue Sep 23 07:21:01 2003
Subject: Topband: Coax shielding
References: <004201c38103$f1938dd0$6401a8c0@DJZJV911>
<00f301c38111$eab16fb0$f39a3b44@youry5sn6dl7l3>
Message-ID: <001901c3816e$a75a3b40$168001d8@akorn.net>
> I thought coax was well shielded until I put 40 db of preamp in the shack.
> The RG-58 picked up broadcast stations at 20 over, with no antenna
connected
> to the coax. RF chokes on each end of the coax almost solves the problem,
> but my next step is to replace the coax with a double shielded type.
If it is shield ingress, a choke will not help at all. It would make no
difference. Chokes only affect common mode currents, not shield integrity.
I ran a test with cheap Radio Shack coax, the type you could see through the
braid, and the leakage from two pieces 30 feet long that were ty-wrapped
tightly together was below the noise floor of my measurement equipment at
HF, over -100dB for crosstalk.
In many years of building RF equipment, I've never seen cable ingress or
egress that was due to anything other than a broken or high resistance
shield connection, or some other system flaw. Every time I find a problem,
it is with shield connections someplace along the line and not shield
quality.
> RF chokes that work well at 160m must still choke well in the broadcast
band
> to kill the noise.
Noise in the BC band isn't noise on 160, even if it did get in. Unless a
non-linear device in the receiving system is seriously overloading, you'd
never hear about out-of-band noise.
What I'd suspect more than anything is improper feedpoints at the loops, or
a defective cable or shield connections elsewhere. Many reference materials
incorrectly claim the "shield" on a loop shields the element, and worse yet
show the loop "shield" as non-symmetrical or the feedline and a mast or
ground attaching to the shield at a point not opposite of the shield gap!
The shield IS the actual antenna. If the antenna "shield" is not perfectly
balanced, it is a source of ingress from common mode currents on the coax.
An antenna "shield" that is not grounded at exact dead bottom center with
the feedline attaching to the inner wire exiting at that same bottom point,
with a gap exactly in the center of the loop top equal-distant from the
feedline entrance point is sure to be improperly balanced.
A small "shielded" loop really isn't any better or much different than a
single turn open wire when installed correctly. When installed incorrectly,
such as being grounded off center, it is actually worse. That's why I always
avoided shielded loops, after my first few years of playing with them.
73 Tom
From tao at skypoint.com Mon Sep 22 21:27:57 2003
From: tao at skypoint.com (Tod - Idaho)
Date: Tue Sep 23 07:21:05 2003
Subject: Topband: T loaded vertical
In-Reply-To: <20030922.170728.-1862457.0.k6se@juno.com>
Message-ID:
Jeez, I am just reacting to the thought of 260 feet of top loading on a
vertical. It almost seems as though one is using a single wire feed line to
feed an horizontal antenna. I may have to get out my ON4UN book and see what
the equations tell me the feed point resistance would be -- I have never
thought of doing something like this and maybe I have missed something that
would work better than what I am using.
Maybe this is just an oddly proportioned DDDR antenna.
Herb, what is the reasoning behind the statement, ""Try to get the current
loop to appear at the connection to the flat top
T. This can be done by modeling or in the old days we would just tape a
small 6 volt bulb on a loop at the T." I suppose that by doing so one will
maximize the current at the highest point above ground and thereby get
maximum radiation from that point. Using Earl's rule of '1/4 wave from its
open end' would suggest that an L that has a flat top of 130 feet or so will
achieve that. A T loaded top should not be necessary (to get the current
maximum at the top of the vertical segment). The T load will, however,
produce a balanced pattern when modeled, the L will not. What happens to the
pattern in real life is probably not the same as either of the models.
A interesting special case would be when the vertical segment is 130 feet.
Now when one adds 130 foot legs for a T or L you are challenged with a feed
point that should be rather high impedance. Presumably one would not need
radials in this case.
Rich, I would not expect the T to be quieter than the L.
As usual, the comments of other folks on this reflector stimulate thought.
Tod, KOTO
-----Original Message-----
From: topband-bounces@contesting.com
[mailto:topband-bounces@contesting.com]On Behalf Of Earl W Cunningham
Sent: Monday, September 22, 2003 7:05 PM
To: herbs@vitelcom.net; rmf01@comcast.net; topband@contesting.com
Subject: Re: Topband: T loaded vertical
Herb, KV4FZ wrote:
"Try to get the current loop to appear at the connection to the flat top
T. This can be done by modeling or in the old days we would just tape a
small 6 volt bulb on a loop at the T."
==========
The highest current point on any antenna is always 1/4 wave from its open
end, regardless of how long the vertical section is. In the case of an
L, this means the horizontal portion would have to be about 130 feet long
to achieve maximum current at the bend in the L.
If the top portion is a T, make sure each of the two sides are equal and
are each about 130 feet long.
73, de Earl, K6SE
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Topband@contesting.com
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From jdube at peoplepc.com Tue Sep 23 00:46:22 2003
From: jdube at peoplepc.com (Joseph Dube)
Date: Tue Sep 23 07:21:08 2003
Subject: Topband: T loaded vertical
References: <20030922.170728.-1862457.0.k6se@juno.com>
Message-ID: <003101c38185$42a2b9e0$624e4804@u5d2s4>
I agree with you 100 % Earl. I wouldn't want the highest current at the
bend though. I believe that there would be too much current in the
horizontal field. About 90 to 100 feet on each side would do the trick.
The currrent would be more evenly distributed on the vertical radiator give
a more vertically polarized signal as a result. I know that it works that
way because I am using that theory here with great success. I have more
current in the vertical field than the horizontal. Works really great.
Joe KK4TR
----- Original Message -----
From: "Earl W Cunningham"
To: ; ; <>
Sent: Monday, September 22, 2003 8:04 PM
Subject: Re: Topband: T loaded vertical
> Herb, KV4FZ wrote:
>
> "Try to get the current loop to appear at the connection to the flat top
> T. This can be done by modeling or in the old days we would just tape a
> small 6 volt bulb on a loop at the T."
> ==========
> The highest current point on any antenna is always 1/4 wave from its open
> end, regardless of how long the vertical section is. In the case of an
> L, this means the horizontal portion would have to be about 130 feet long
> to achieve maximum current at the bend in the L.
>
> If the top portion is a T, make sure each of the two sides are equal and
> are each about 130 feet long.
>
> 73, de Earl, K6SE
> _______________________________________________
> Topband mailing list
> Topband@contesting.com
> http://lists.contesting.com/mailman/listinfo/topband
>
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From btippett at alum.mit.edu Tue Sep 23 08:35:39 2003
From: btippett at alum.mit.edu (Bill Tippett)
Date: Tue Sep 23 07:36:21 2003
Subject: Topband: Reflector
Message-ID: <6.0.0.22.0.20030923073442.030c0610@pop.vnet.net>
I just deleted about 50 failure notice messages that
were bounced back to the reflector from various ISP's. These
were apparently in response to messages (spoofing the
reflector as the sender) that contained viruses.
Just for everyone's information, I believe it is impossible for
the reflector to send viruses because we cannot send attachments.
Besides, in moderated mode, the moderator must approve each
message that goes out.
No more comments on this are necessary...if you don't
have an anti-virus, you can get a free one here, and remember to
update the signature files regularly:
http://www.grisoft.com/us/us_dwnl_free.php
73, Bill W4ZV
From w8ji at contesting.com Tue Sep 23 08:55:57 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Tue Sep 23 08:35:21 2003
Subject: Topband: T loaded vertical
References:
Message-ID: <001501c381c9$a7755500$2e8001d8@akorn.net>
It's not how our antennas work, it's how we *think* they work that makes us
feel good.
> Jeez, I am just reacting to the thought of 260 feet of top loading on a
> vertical. It almost seems as though one is using a single wire feed line
to
> feed an horizontal antenna. I may have to get out my ON4UN book and see
what
> the equations tell me the feed point resistance would be -- I have never
> thought of doing something like this and maybe I have missed something
that
> would work better than what I am using.
Maximum radiation resistance occurs when current integrated over the
vertical section is as high as possible, which means maximum current
mid-height in the vertical section.
Feedpoint resistance is not the same as radition resistance, of course. With
a poor ground system maximum gain would occur with a larger flat top and
current further up from the center. With a reasonable ground maximum gain
would appear when current maximum is near mid-height. With a good ground,
at mid-height or lower. But all of these are small changes anyway. The real
cure is to use the best ground system possible.
> Maybe this is just an oddly proportioned DDDR antenna.
The flat top of the DDRR being close to the groundplane only "loads" the
short vertical antenna, and does so somewhat inefficiently. Only the very
short vertical section radiates useful RF. The DDRR isn't a good antenna,
typically in the few percent efficiency range, because of the large flattop
and short vertical radiating section.
With a T or L antenna, the optimum length would depend on the ground system
and vertical height. I don't think there is any combination of modest
height vertical and reasonable ground loss that would have maximum
performance with current maxima exactly at the top of the vertical. As the
ground system gets better, where you place the current maximum generally
means less and less (fractions of a dB).
Not using any ground or a poor ground wouldn't be a good idea, unless the
antenna is 100 feet above ground at the lowest point! Electric fields induce
large amounts of loss in soil also. We often forget about that and only
consider direct current paths.
I'd use whatever made me happy, no one else would ever notice the signal
change. I wanted a real signal change, I'd work on the ground system.
73 Tom
From w1to at adelphia.net Tue Sep 23 09:16:46 2003
From: w1to at adelphia.net (Tom Homewood)
Date: Tue Sep 23 08:35:23 2003
Subject: Topband: T Vertical
Message-ID: <017001c381cc$8f348080$0a00a8c0@mbd>
I modeled a T vertical on EZNEC. My target was to get a design with zero
reactance at the feed point. The vertical distance was per W1TSP's criteria.
With 59 feet of vertical, two horizontal wires of 64 feet each and eight 60
foot radials. I got a feed impedance of 18.19 + J 0.4599 ohms at 1.83 mHz.
The take off angle is 26 degrees.
73, Tom, W1TO
From w1to at adelphia.net Tue Sep 23 09:30:06 2003
From: w1to at adelphia.net (Tom Homewood)
Date: Tue Sep 23 08:35:25 2003
Subject: Topband: T Vertical
Message-ID: <018201c381ce$6c10eb00$0a00a8c0@mbd>
This is a follow-up to my previous post. That calculation was done with
MININEC ground.
When I changed just the ground type to Real/High Accuracy the impedance
changed to 23.51 + J 0.5327 ohms.
In both cases I used Medium conductivity.
This should give Rich, W1TSP, an idea of what to expect. If the horizontal
wire droop, ala an inverted vee look, the impedance will be lower.
73, Tom, W1TO
From herbs at vitelcom.net Tue Sep 23 11:41:23 2003
From: herbs at vitelcom.net (Herb Schoenbohm)
Date: Tue Sep 23 10:05:02 2003
Subject: Topband: T loaded vertical
In-Reply-To:
References:
Message-ID: <3F704D83.4080400@vitelcom.net>
Tod, I should have been more specific. Top loading with a T type
marconi with a short vertical 60 foot down lead can be peaked to
reasonable performance with a 75 foot (each side of center) flat top
with the method I described. (If I recall the modeling done on this a
longer flat top has a slightly lower take off angle and off course a
higher feed point impedance.) Yes Earl is right about the current
maximum always appearing 1/4 wave from each end. Yet I have found that
a shorter flat top can be a terrific performer on top band as long as
care is taken to match the feed point at the base. (W8UVZ and K8GG
worked JA's from my QTH with only this type of antenna during the CQ 160
meter Contest a few years ago.)
The marconi T is a superb DX limited space antenna for 160 meters
especially in restricted space circumstances. It is also a relatively
efficient antenna as long as radials (in the ground or above the ground)
are employed.
73
Herb, KV4FZ
Tod - Idaho wrote:
>Jeez, I am just reacting to the thought of 260 feet of top loading on a
>vertical. It almost seems as though one is using a single wire feed line to
>feed an horizontal antenna.
>
>Herb, what is the reasoning behind the statement, ""Try to get the current
>loop to appear at the connection to the flat top
>T. This can be done by modeling or in the old days we would just tape a
>small 6 volt bulb on a loop at the T."
>
>
>
>
>
>
>
>
From k6se at juno.com Tue Sep 23 09:32:19 2003
From: k6se at juno.com (Earl W Cunningham)
Date: Tue Sep 23 13:08:07 2003
Subject: Topband: T loaded vertical
Message-ID: <20030923.083246.-1866877.1.k6se@juno.com>
Tod, K0TO wrote:
"A interesting special case would be when the vertical segment is 130
feet. Now when one adds 130 foot legs for a T or L you are challenged
with a feed point that should be rather high impedance. Presumably one
would not need radials in this case."
==========
True, the feedpoint impedance would be quite high, but let's not get that
mixed up with the radiation resistance of the antenna.
A good ground radial system is still very necessary to minimize ground
losses!!!
73, de Earl, K6SE
From tao at skypoint.com Tue Sep 23 13:03:30 2003
From: tao at skypoint.com (Tod - Idaho)
Date: Tue Sep 23 13:08:09 2003
Subject: Topband: T loaded vertical
In-Reply-To: <20030923.083246.-1866877.1.k6se@juno.com>
Message-ID:
Just being a bit defensive, probably without need, I would like to assure
the folks commenting on this topic that I did intend to say 'feed point
impedance' and did not mean 'radiation resistance' in my previous comments.
As Earl says, "..let's not get that (feed point impedance) mixed up with the
radiation resistance of the antenna."
I know that in one post I wrote that I had measured about 12-14 ohms R at
the base of an antenna --- that is not (I don't believe it to be at least)
the radiation resistance of the antenna which I estimated to be closer to
2-4 ohms on 160 meters. It is simply the Resistive part of the Impedance I
was going to have to 'adjust' by a matching network to something closer to
50 ohms before sending it off to my station.
Tom, Earl and others have pointed out in different writings the fact that
the resistance of the ground system is added to the radiation resistance of
the antenna and that will determine the resistance in the measurements made
at the feed point. The radiation resistance of a vertical antenna is a
function of vertical wire length, diameter, top loading, etc.
All this stuff is in the ARRL antenna book (to some degree) and in ON4UN's
Low Band DXing book (to a large measure)--- but sometime requires careful
reading followed by a period (often long) of contemplation.
Tod, KOTO
-----Original Message-----
From: Earl W Cunningham [mailto:k6se@juno.com]
Sent: Tuesday, September 23, 2003 10:32 AM
To: tao@skypoint.com; topband@contesting.com
Subject: Re: Topband: T loaded vertical
Tod, K0TO wrote:
"A interesting special case would be when the vertical segment is 130
feet. Now when one adds 130 foot legs for a T or L you are challenged
with a feed point that should be rather high impedance. Presumably one
would not need radials in this case."
==========
True, the feedpoint impedance would be quite high, but let's not get that
mixed up with the radiation resistance of the antenna.
A good ground radial system is still very necessary to minimize ground
losses!!!
73, de Earl, K6SE
From marc.wullaert3 at pandora.be Tue Sep 23 20:12:37 2003
From: marc.wullaert3 at pandora.be (Marc - on4ma-)
Date: Tue Sep 23 17:57:20 2003
Subject: Topband: FVR spitfire Aray .
Message-ID: <006001c381f5$e481d370$6501a8c0@on4mamarc>
Hi,
i'm looking for the dimensions for the spitfire array.
There where some files (presentation ) but there is a bad link on the yccc
webpage
I need de dimensions both for 160m and 80m .
Any help pse .Some have the presentation files for me ?
73/dx
ON4MA Marc
DXCLUSTER CONCENTRATOR
visit www.on5oo.com
From ua3ap at mail.ru Wed Sep 24 08:55:36 2003
From: ua3ap at mail.ru (=?koi8-r?Q?=22?=Sergei Kulyov=?koi8-r?Q?=22=20?=)
Date: Wed Sep 24 07:32:22 2003
Subject: Topband: RX antenna on roof
Message-ID:
Hello topbanders:
Could you please advise on RX antenna desing which can be use atop of multy store building?
Appreciate for help
73, Sergei - UA3AP
Moscow
From kn4lf at tampabay.rr.com Wed Sep 24 10:18:52 2003
From: kn4lf at tampabay.rr.com (Thomas Giella KN4LF)
Date: Wed Sep 24 10:05:15 2003
Subject: Topband: Tee Antenna
Message-ID: <004f01c3829e$665fbda0$6501a8c0@tampabay.rr.com>
I have been using "elevated highest current" Tee antennas for a good while and they are great performers. I designed mine to place the highest current point midway up the 80 foot vertical section. This arrangement was what I called a voltage fed Tee which used a parallel network at the base of the antenna to tune our reactance.
At the moment I'm using a current fed Tee. I have some information about the Tee antenna on my website at http://www.kn4lf.com/kn4lf.htm .I also have an in depth article online about the Tee antenna at http://www.kn4lf.com/kn4lf2.htm .
73,
Thomas F. Giella, KN4LF
Plant City, FL, USA
EL87WX
KN4LF 160 Meter Amateur Radio Resources & More:
http://www.kn4lf.com/kn4lf.htm
Florida Space & Atmospheric Weather Institute:
http://www.kn4lf.com/fsawi.htm
---
Outgoing mail is certified Virus Free Thanks To Grisoft AVG.
Checked by AVG anti-virus system (http://www.grisoft.com).
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From marc.wullaert3 at pandora.be Wed Sep 24 18:45:42 2003
From: marc.wullaert3 at pandora.be (Marc - on4ma-)
Date: Wed Sep 24 12:59:44 2003
Subject: Topband: Re: FVR spitfire Aray .
References: <5.2.0.9.2.20030923234028.01a2d4e0@mail.adelphia.net>
Message-ID: <006901c382b2$ea95c7e0$6501a8c0@on4mamarc>
Thanks ,
It is working now.Danny ON7NQ did the magic trick.
The website designer used some bad colors for this page
if you use CTRL-A you see the presentation !!
Thanks to the others who send me the needed dimensions !
Back to my garden and lay down radials for the 1/4wave 80m tower.
73/ dx
on4ma marc
From na4d at kih.net Thu Sep 25 14:05:29 2003
From: na4d at kih.net (LLOYD CURRY)
Date: Thu Sep 25 14:52:28 2003
Subject: Topband: capacitance hat
Message-ID: <410-22003942517529200@kih.net>
I am about to finish an insulated tower vertical. I have a 10 foot section,
then an insulator, then 100 ft of 25g and a 10 ft mast out the top. The
tower is insulated with Phillystran guy wire. How much capacitance hat
will I need to resonate to about 1830 khz? Should I put it at the top of
the mast or is where the mast exits the top section ok? Finally, I am
considering placing my Cushcraft 6 el 6 mt. yagi (20 ft boom) on this
tower. Will it provide enough capacitance? Any comments will be
appreciated. Lloyd Curry NA4D
LLOYD CURRY
na4d@kih.net
Why Wait? Move to EarthLink.
From gmguerin at voyager.net Thu Sep 25 23:55:46 2003
From: gmguerin at voyager.net (George & Marijke Guerin)
Date: Fri Sep 26 06:09:24 2003
Subject: Topband: capacitance hat
References: <410-22003942517529200@kih.net>
Message-ID: <003e01c383d9$b12c53c0$988d59cf@yourkf1y8xksrv>
Lloyd, et.al.:
10 sections of 25G add up to about 97.375 feet since the legs telescope
about 3.5 inches at each joint. If you put the 6 meter beam on the top of
the 2 inch diameter 10 foot high mast, assuming the reflector and directors
are grounded to the boom, you will have between 15 and 20 feet of top
loading.. it is best to model it and find out.
That would mean the electrical length could be between 122 and 127+ feet or
resonant somewhere between 1840 and 1920 KHz. Since one does not get much
radiation off the top 25% of a quarter wave vertical, I would recommend
enough top loading to at least get down to the center frequency of interest,
where the impedance will be Zant = 36 ohms plus ground losses. If you have
a very good radial system, that could mean the impedance, Zant = 36 + 0 ohms
ground loss. That would mean about 30 feet of wire on each guy line from
the top of the tower down toward the guy anchors. If your ground is very
good, consider another 10 to 15 feet of top loading (40 - 45 feet of wire on
each top guy line) to bring the impedance up to Zant = 50 + jXL ohms and
then tune out the inductive reactance with a series capacitor at the feed
point. The inductive reactance could be around +60j to +80j ohms which
would be tuned out by a capacitor in the range of 1000 to 1500 pfd at 1830
KHz.
73, George K8GG
----- Original Message -----
From: "LLOYD CURRY"
To:
Sent: Thursday, September 25, 2003 1:05 PM
Subject: Topband: capacitance hat
> I am about to finish an insulated tower vertical. I have a 10 foot
section,
> then an insulator, then 100 ft of 25g and a 10 ft mast out the top. The
> tower is insulated with Phillystran guy wire. How much capacitance hat
> will I need to resonate to about 1830 khz? Should I put it at the top of
> the mast or is where the mast exits the top section ok? Finally, I am
> considering placing my Cushcraft 6 el 6 mt. yagi (20 ft boom) on this
> tower. Will it provide enough capacitance? Any comments will be
> appreciated. Lloyd Curry NA4D
>
>
> LLOYD CURRY
> na4d@kih.net
> Why Wait? Move to EarthLink.
>
>
> _______________________________________________
> Topband mailing list
> Topband@contesting.com
> http://lists.contesting.com/mailman/listinfo/topband
>
>
From rtym at ippt.gov.pl Fri Sep 26 11:31:05 2003
From: rtym at ippt.gov.pl (Ryszard Tymkiewicz)
Date: Fri Sep 26 07:35:37 2003
Subject: Topband: 3C0V
Message-ID: <01f701c38408$87a2bce0$2f355194@ippt.gov.pl>
Hi All,
I exchanged e-mails with Franz DJ9ZB a few days ago regarding his activity
on 160m from Annobon. As you know /if everything goes well/ the group should
be active as 3C0V from 27th September till 10th October.
I suggested Franz to use 1821-1824 kHz and rather + 0.5 kHz /like 1821,5 ; 1822,5 kHz etc/
than exactly 1821,1822 ..etc. I asked him also to work split ~2kHz and he answered
he will try.
They will use Titanex V80 and although there is only one strictly CW operator EA5YN
Franz DJ9ZB will try also to be there himself.
73 GL and CU in pileups
Rys
SP5EWY
rtym@ippt.gov.pl
P.S.
Also more details about Juan de Nova :
Europa Island, FR---.
Europa, FR A team of eight French military operators will be active from Europa Island (AF-009)
from November 22nd until December 5th or 6th.
Europa is a small island that is part of the DXCC Entity called - Europa & Juan de Nova.
They hope to have three stations active on 6 through 160 meters on SSB, CW and digitals modes.
The team plan to operate in the CQ World Wide CW DX Contest on last weekend of November.
Be aware of the possibility that the operation could be cancelled if the international situation were to
unfold, as these operators would have to all go on active duty because of there military jobs. It has
been a difficult project to secure permission to go to this rare island, however with the persistence of
F5OGL, Didier and his team they did receive the blessing from the general headquarters to go. Europa
ranks # 6 (World wide) on The DX Magazine's 2002 Most Wanted Countries list. In Europe it ranks # 10
and in the US it is # 6.
Team members for this operation include F5OGL, Didier, F5CW, Dany; F5JKK, Eric; F5KIN, Stephane;
F5IRO; F0CRS, David; TU5AX, Chris and another one operator. The callsign for this most anticipate
DXpedition will be announced when the operation begins. QSL cards will be handled by F5OGL and
may be sent via the bureau or direct to Didier Senmartin, P.O. Box 7, 53320 Loiron, France.
From K8LV1 at aol.com Fri Sep 26 16:10:54 2003
From: K8LV1 at aol.com (K8LV1@aol.com)
Date: Fri Sep 26 16:12:55 2003
Subject: Topband: Fwd: Open wire lines - fact and fiction
Message-ID: <1c8.f85a5a0.2ca5e93e@aol.com>
From k4kyv at hotmail.com Fri Sep 26 23:44:49 2003
From: k4kyv at hotmail.com (Donald Chester)
Date: Fri Sep 26 19:15:10 2003
Subject: Topband: This is from FCC Digest re BPL
Message-ID:
Addressing the United Powerline Council's annual conference September 22 in
Arlington, Virginia, FCC Commissioner Kathleen Q. Abernathy expressed
unabashed enthusiasm for BPL and recommended a combination of regulatory
restraint and the elimination or substantial modification of existing rules
as steps along the "path to Enlightenment." Here is the complete text, form
the FCC Digest of 22SE03:
Reaching Broadband Nirvana
United PowerLine Council Annual Conference Remarks of Commissioner
Kathleen Q. Abernathy
September 22, 2003 (As prepared for delivery)
Thank you very much for inviting me to speak with you. I am very
excited about broadband-over-powerline technology. I
have seen it in action, and I believe it has a very bright future. It
is a real honor to be your keynote speaker at this
important juncture for BPL.
As a regulator, I am keenly interested in BPL technology for a number
of reasons. One of my central objectives as an FCC commissioner is to
facilitate the deployment of broadband services to all Americans. I
also fundamentally believe that the FCC can best promote consumer
welfare by relying on market forces, rather than heavy-handed
regulation. The development of BPL networks will serve both of these
key goals. It will not only bring broadband to previously unserved
communities, but the introduction of a new broadband pipeline into the
home will foster the kind of competitive marketplace that will
eventually enable the Commission to let go of the regulatory reins. I
want consumers to have a choice of multiple, facilities-based
providers, including not only cable and DSL, but also powerline,
wireless, and satellite services. Such a robustly competitive and
diversified marketplace is something I would call broadband Nirvana.
We will not get there overnight, but the continuing development of BPL
technology is a major step forward.
While the long-term objective is a robustly competitive marketplace
that is free of regulatory distortions, a more immediate question is:
What should the FCC do to help foster such an environment? Sticking
with my Nirvana metaphor, I guess the question would be, what is the
path to enlightenment?
I believe the answer, in short, is regulatory restraint. It is
tempting for regulators to take every new technology or service that
comes along and apply the same rules that govern incumbent services.
After all, regulatory parity and a level playing field are
intuitively appealing concepts. But I believe that it would be a huge
mistake to carry forward legacy regulations whenever new technology
platforms are established. Many of our regulations are premised on
the absence of competition, and when that rationale is eroded, we
must not reflexively hold on to regulations that no longer serve
their intended purpose. In fact, many of our old rules not only become
unnecessary as markets evolve, but they can be fatal to new services
that need room to breathe.
The Nascent Services Doctrine applying more stringent regulations to
wireline providers at a minimum must be reconsidered. As other
platforms, including BPL and wireless, become more widely available,
that will further undermine the justification for regulating
incumbent LECs broadband services as if they were the only available
offerings. When the Commission completes this rulemaking, I expect
that we will eliminate many existing rules and substantially modify
others; the central question is the degree of regulation that will
remain during the transition to a more robustly competitive market.
Finally, it is important to recognize that although the emergence of
new platforms like BPL will eliminate the need for many
competition-related regulations, other types of regulation may well
remain necessary. For example, the FCC must implement public policy
goals unrelated to competition, or even at odds with competition.
Universal service and access for persons with disabilities are
examples of this kind of regulation. These public policy goals
generally should be applied to all service providers, to the extent
permitted by the Communications Act. The FCC also must intervene to
prevent competitors from imposing externalities on one another and to
protect consumers where market failures are identified. Although, as
I have noted, the Commission was right to refrain from imposing
heavy-handed price and service-quality regulations on PCS services
when the were introduced, it was also right to adopt strict
interference rules to prevent competitors from externalizing their
costs. The same principle will apply to BPL. They key point is that,
while some degree of regulation is both inevitable and desirable, we
should ensure that it is narrowly tailored to the particular
governmental interests at stake. I appreciate the opportunity to
share these thoughts with you, and I would be happy to answer a few
questions if we have time.
YOU CAN EMAIL MISS ABERNATHY AT THE FOLLOWING ADDRESS AND I URGE EVERYONE TO
DO SO.
kabernat@fcc.gov
-Don K4KYV
_________________________________________________________________
Share your photos without swamping your Inbox. Get Hotmail Extra Storage
today! http://join.msn.com/?PAGE=features/es
From Hal553 at aol.com Sat Sep 27 09:24:57 2003
From: Hal553 at aol.com (Hal553@aol.com)
Date: Sat Sep 27 09:48:36 2003
Subject: Topband: Antenna on small lot
Message-ID:
I've always wanted to work 160m CW. I can put a wire antenna up to about 40
feet maximum. The max length will be in the vicinity of 90 feet. Am I wasting
my time and should I stick to 40m and above?
Thanks for any insight.
Hal
KB3HAA
From W4EF at dellroy.com Sat Sep 27 08:59:22 2003
From: W4EF at dellroy.com (Michael Tope)
Date: Sat Sep 27 12:10:16 2003
Subject: Topband: Antenna on small lot
References:
Message-ID: <021701c38507$ef9a54c0$0100a8c0@1800XP>
Hal,
Try an inverted L (40 ft vertical, 50 ft horizontal). Feed the
wire against ground with the appropriate impedance matching
network and as many ground radials as you can get down.
You will be suprised at how much DX you can work with
such a system (even with 100 watts). The key is the radial
system. You can use a similar arrangement on 80 meters.
I used a similar arrangement with only a 27 ft vertical section
and got surprisingly good results with about 25 random
length ground radials (average length about 50').
Good Luck!
Mike, W4EF....................................
----- Original Message -----
From:
To:
Sent: Saturday, September 27, 2003 5:24 AM
Subject: Topband: Antenna on small lot
> I've always wanted to work 160m CW. I can put a wire antenna up to about
40
> feet maximum. The max length will be in the vicinity of 90 feet. Am I
wasting
> my time and should I stick to 40m and above?
> Thanks for any insight.
> Hal
> KB3HAA
From rtym at ippt.gov.pl Sat Sep 27 17:14:06 2003
From: rtym at ippt.gov.pl (Ryszard Tymkiewicz)
Date: Sat Sep 27 13:21:41 2003
Subject: Topband: 3C0
Message-ID: <004e01c38501$9d9ed700$51365194@rys>
Hi All
Franz DJ9ZB told me they will put up the V80 for 40/80/160 tomorrow
and they should be the next night on Low Bands.
73 GL
Rys
SP5EWY
From ac7a at earthlink.net Sat Sep 27 11:45:51 2003
From: ac7a at earthlink.net (ac7a@earthlink.net)
Date: Sat Sep 27 13:49:33 2003
Subject: Topband: Antenna on small lot
Message-ID: <12165090.1064684751912.JavaMail.root@thecount.psp.pas.earthlink.net>
Hal,
There are many of us on 160 meters who sucessfully operate with pint-size antennas. My antenna is a modest 45' tall and it allows me to enjoy the band. Although a vertical, it also occupies some horizontal space as well.
A 40' top-loaded vertical is likely a good bet. The top loading should can consist of a large top hat, preferably symmetrical in layout. Doing so minimizes high-angle, horizontally polarized radiation. The top hat doesn't have to be hat shaped; it can be as simple as equally long, opposing horizontal wires. However, with a 40' vertical height, the horizontal wire lengths will be in excess of 100' - in both directions. One way to overcome the problem is to take the far ends of the wires, fold them back, and connected the ends to each other. This results in a much more compact top hat. Using this technique has little affect on the antenna's performance. The greater the spacing used between the folded wires the shorter the horizontal span required. My 160 antenna uses the folded top-hat arrangement and takes much less space than an 80-meter dipole.
If you would like more information on this subject, you can directly contact me. I've had a few articles published on the subject and they should answer most any questions you might have.
Don't even think about settling for 40 and above. You'll miss out on way too much of the fun.
Regards, Thomas - AC7A (Tucson)
-----Original Message-----
From: Hal553@aol.com
Sent: Sep 27, 2003 5:24 AM
To: topband@contesting.com
Subject: Topband: Antenna on small lot
I've always wanted to work 160m CW. I can put a wire antenna up to about 40
feet maximum. The max length will be in the vicinity of 90 feet. Am I wasting
my time and should I stick to 40m and above?
Thanks for any insight.
Hal
KB3HAA
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From ken.d.brown at verizon.net Sat Sep 27 09:31:29 2003
From: ken.d.brown at verizon.net (Ken Brown)
Date: Sat Sep 27 15:05:19 2003
Subject: Topband: Antenna on small lot
References:
Message-ID: <3F75D781.4000205@verizon.net>
Hi Hal,
I have an inverted L. The support for the verical section is a strap
around a palm tree. In the last several months the strap has slid down
the tree, so that it is now less than 40 feet up. The rest of the
antenna slopes up to maybe 50 feet high, and then back down to around 30
feet high. It is more like an inverted J than an L. I have about 30
radials, that are presently all bunched together, because I had to mow
the lawn. A couple of nights ago I worked ZL and VK on 160 meters with
this antenna. I am in Hawaii, so thats not the DX it would be for you.
Still that is good DX.
So I say: Go for it! We will all be looking for you on 160 meters.
Ken N6KB
Hal553@aol.com wrote:
>I've always wanted to work 160m CW. I can put a wire antenna up to about 40
>feet maximum. The max length will be in the vicinity of 90 feet. Am I wasting
>my time and should I stick to 40m and above?
>Thanks for any insight.
>Hal
>KB3HAA
>_______________________________________________
>
>
From dennis.peterson at machlink.com Sat Sep 27 16:07:14 2003
From: dennis.peterson at machlink.com (dennis peterson)
Date: Sat Sep 27 19:08:12 2003
Subject: Topband: frequency updates, changes, new additions etc
Message-ID: <000001c38532$f2ff9140$520acf42@machlink.com>
Topbanders;
I would like to update the Topband Frequency allocations listing but I
need your help.............
Please send any additions, changes or deletions to me before October 5,
2003. I would like to update the listing and have it current for the
upcoming season.
Thanks K?CKD
Dennis G. Peterson
S U R E ---
Skills Unlimited Resources Enterprise
Home, Lawn & SENIOR Services
http://www.machlink.com/~sure my business web site
http://www.machlink.com/~k0ckdennis amateur radio web site
http://www.machlink.com/~classof63 class of 1963 web site
cell:?????? 563-299-4224
home:??? 563-263-2272
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From n6wg at earthlink.net Sat Sep 27 14:12:38 2003
From: n6wg at earthlink.net (Bob Tellefsen)
Date: Sat Sep 27 19:08:14 2003
Subject: Topband: Antenna on small lot
In-Reply-To:
Message-ID:
Hello Hal
I'm on the edge of San Francisco Bay, way over on the left edge of things.
The antenna here is a 50-ft top-loaded wire vertical. The top loading is
a homebrew airwound coil and 5 30-ft top loading wires. My back yard is
way too small for a ground radial system, so I went overhead with a
counterpoise system. I have 21 wires, 3 ft apart, stretching from the top
of my back fence to the back edge of the house roof, then laying on the
roof to the front of the house.
It works really well, considering I only run 5w here with a K2. I'm one
state (RI) away from completing QRP WAS on 160m. Plus I enjoy working all
the top band cw contests.
A good receiving antenna will make a big difference too. I'm using a Flag
receiving loop here, with a homebrew preamp.
Hope you will jump in and join the fun. See you in the contests.
73, Bob N6WG
From tao at skypoint.com Sat Sep 27 16:33:10 2003
From: tao at skypoint.com (Tod - Idaho)
Date: Sat Sep 27 19:08:16 2003
Subject: Topband: Antenna on small lot
In-Reply-To:
Message-ID:
Hal, if you can locate your small lot at a low latitude and relatively close
to an ocean coastline you will find that the small lot will not prevent low
band success.
Tod, KOTO
-----Original Message-----
From: topband-bounces@contesting.com
[mailto:topband-bounces@contesting.com]On Behalf Of Hal553@aol.com
Sent: Saturday, September 27, 2003 7:25 AM
To: topband@contesting.com
Subject: Topband: Antenna on small lot
I've always wanted to work 160m CW. I can put a wire antenna up to about 40
feet maximum. The max length will be in the vicinity of 90 feet. Am I
wasting
my time and should I stick to 40m and above?
Thanks for any insight.
Hal
KB3HAA
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From K8LV1 at aol.com Sat Sep 27 19:53:32 2003
From: K8LV1 at aol.com (K8LV1@aol.com)
Date: Sat Sep 27 19:08:18 2003
Subject: Topband: Open Wire Lines - Fact and Fiction
Message-ID:
While recently reviewing some recent postings RE: open wire transmission
lines, I found some controversial info to which I would like to add my 2 cents
worth. Particularly intersting was the claim by W8JI (08/034/04) that he had
built a perfect transmission line (almost). This triggered one of my alarms, the
one that trips on statements that approximate "If it is too good to be true, it
probably isn't". The data claims a 2-wire line, almost a third of a mile
long+broadband transformers at both ends, ?with a total attenuation of .087dB
(2%), or .005db/100'. This data contradicts enough established RF engineering
dogma that I simply can't believe it, and I believe that his measurments are
flawed.The following three points support my opinion.
First, the line was described as 1500 feet long, #8 copper with 2 inch
spacing, with details of the construction omitted. Assuming a straightforward
construction, my calculations, based upon standard EM principles, shows that the
attenuation constant at 4MHZ for an IDEAL line (no loss in the spacers or the
medium) would be .00012 nepers/m. (RF units) or .03 db/100feet (ham units.) For
1500 feet, this works out to .46db of attenuation (about 11% loss). Again, this
is a totally optimistic calculation which assumes absolutely NO losses of any
kind other than the .1ohm/m. of AC ohmic resistance at 4MHZ (properly
corrected for skin-depth). These numbers are chiseled in stone - pure, basic,
electronics. ?
Second, the impedance of the line calculates to 412 ohms, which requires the
noted transformers to get it down to 50 ohms. Broadband transformers, as
stated in the data, would have to be constructed using ferrite cores. It is not
possible to build such transformers, especially at transmitting power levels,
which do not have losses that range from small but noticable, to overwhelming. If
you doubt that, just spend about 10 minutes talking to anyone who has ever
designed a broadband PA. The idea of building these matching transformers with
power losses in the 1% range is just not thinkable. It would be possible to
build transformers using low-loss coax, which would not be fully broadband, but
would have losses that could be kept down to a few tenths of a db. over a
single band.
Third, contrary to popular belief AND statements that I have seen posted
here, even a perfectly 'balanced' open wire line will radiate some RF (an
authoritative, early reference for this is the article by Sterba in Proc.IRE, 1932,
p.1200) The statement that zero-radiation will occur is an approximation, that
is useful when used properly. But if you want to engage in analysis of effects
down in that 1% range, it won't work there. That is why the 4 wire 'X-line'
was invented, to reduce the small but known amount of residual magnetic dipole
radiation from the parallel line, which is really a long,skinny loop (i.e. a
magnetic dipole). By using two equal and opposed lines, which is what the X-line
really is, the magnetic dipole fields of each pair are highly cancelled,
leaving a residual magnetic quadrupole field (whose radiation is orders of
magnitude lower.) By reciprocity, it also greatly reduces the undesired signal
capture in RX mode, which was one of the motivations for its invention.
An easier, intuitive way to fathom this phenomenon is as follows. Imagine
taking that 1500 foot by 2 inch loop and stretching it out to a perfect square
(which would be 750 feet on a side.) Such a big loop is obviously going to do
some serious radiating at 4 MHz (or any other frequency for that matter). Now
begin to pull the sides back in while lengthening it, gradually restoring it to
the original line configuration. Is there any basic physical reason why at
some "magic" value of the width of the loop, it should suddenly stop radiating?
Of course not. The radiated field will just continue to decrease until the
width shrinks to zero.
Here is another interesting observation. When I went back and reviewed
Sterba's article, there were many articles around that time on transmission line
theory and measurements.The early radio antenna pioneers, like Brown, Kraus,
Sterba, etc. were laying down the basic theory of HF radiating and transmission
systems, which is all documented in the radio and electronics publications of
the 30's and 40's I ?noticed a general pattern in all of them, that the
experimental measurements (of ?line losses) were ALWAYS ?higher by factors of 2-3 than
the theoretical calculations based just upon the RF resistance of the
conductors (as I used in my first point above.) Hence, for anyone wishing to engage
in this type of loss estimation, I would suggest using the standard formulas
for loss (based on pure ohmic loss) and then doubling the result.
In conclusion, I do not think an open wire (2) line with a loss of .005
db/100' ?is possible ?in the HF ham bands. I would say that a long line like this
would exhibit at least 1 db. total loss, from one 50ohm port to the other.
73
Eric von Valtier K8LV
From k9ay at k9ay.com Sun Sep 28 02:40:10 2003
From: k9ay at k9ay.com (K9AY)
Date: Sun Sep 28 05:57:04 2003
Subject: Topband: Open Wire Lines - Fact and Fiction
References:
Message-ID: <000901c3858b$5d906b80$a49ffea9@k9ay>
This note piqued my interest and I reached the conclusion that the
right answer lies closer to W8JI's claims than K8LV's calculations.
To wit...
K8LV -- Assuming a straightforward construction, my calculations, based upon
standard EM principles, shows that the attenuation constant at 4MHZ for an
IDEAL line (no loss in the spacers or the medium) would be .00012 nepers/m.
(RF units) or .03 db/100feet (ham units.) For 1500 feet, this works out to
.46db of attenuation (about 11% loss). Again, this is a totally optimistic
calculation which assumes absolutely NO losses of any
kind other than the .1ohm/m. of AC ohmic resistance at 4MHZ (properly
corrected for skin-depth). These numbers are chiseled in stone - pure,
basic, electronics.
K9AY -- Frequency-dependent effects, including skin effect, are minimal
at 2 MHz (not much more at 4 MHz), so AC (RF) loss is essentially the
same as DC resistive loss, which is 0.04 dB for 1500 ft. of (2) #8 wires.
(1.90 ohms resistance, 412 ohm load).
K8LV -- Second, the impedance of the line calculates to 412 ohms, which
requires
the noted transformers to get it down to 50 ohms. Broadband transformers, as
stated in the data, would have to be constructed using ferrite cores. It is
not possible to build such transformers, especially at transmitting power
levels, which do not have losses that range from small but noticable, to
overwhelming. If you doubt that, just spend about 10 minutes talking to
anyone who has ever designed a broadband PA. The idea of building these
matching transformers with power losses in the 1% range is just not
thinkable. It would be possible to build transformers using low-loss coax,
which would not be fully broadband, but would have losses that could be kept
down to a few tenths of a db. over a single band.
K9AY -- A properly designed transmission line transformer using the correct
wire size, winding style and core material can have a loss well under 0.1
dB,
as low as 0.03 to 0.5 dB in the frequency range of of optimum performance.
(Ref. "Transmission Line Transformers" by Sevick.)
K8LV -- Third, contrary to popular belief AND statements that I have seen
posted
here, even a perfectly 'balanced' open wire line will radiate some RF ....
...An easier, intuitive way to fathom this phenomenon is as follows. Imagine
taking that 1500 foot by 2 inch loop and stretching it out to a perfect
square (which would be 750 feet on a side.) Such a big loop is obviously
going to do some serious radiating at 4 MHz (or any other frequency for that
matter). Now begin to pull the sides back in while lengthening it, gradually
restoring it to the original line configuration. Is there any basic physical
reason why at some "magic" value of the width of the loop, it should
suddenly stop radiating? Of course not. The radiated field will just
continue to decrease until the width shrinks to zero.
K9AY -- The field intensity from a loop is proportional to the area enclosed
by the loop -- in dB, that's 20 log(Area1/Area2). Applied to the above
analogy, radiation from a 2-inch by 1500 foot loop is -67 dB relative to a
750 by 750 foot loop. -67 dB corresponds to a loss of 0.0000009 dB
(e.g. 0.2 mW out of 1 kW). That's not much radiation.
K8LV -- In conclusion, I do not think an open wire (2) line with a loss of
.005
db/100' is possible in the HF ham bands. I would say that a long line like
this would exhibit at least 1 db. total loss, from one 50ohm port to the
other.
K9AY -- 0.04 dB line loss + (2 x .05 dB) transformer losses = 0.14 dB
For comparison, the loss in 1500 ft. of 7/8" foam dielectric Heliax(R) at
2 MHz is 0.75 dB.
73, Gary
K9AY
From jmata at tinet.org Sun Sep 28 11:45:53 2003
From: jmata at tinet.org (JOSE MATA EA3VY)
Date: Sun Sep 28 05:57:07 2003
Subject: Topband: 3C0V
Message-ID: <000b01c3859d$0c403500$0100a8c0@mshome.net>
Vicente EA5YN will be the operator for Topband.
Early this month he called me and we had a series of long telephone calls.
He is extremely interested in this Topband face of the expedition . My
personal belief is that he will do the best possible for the Topbanders,
more than any other of the group.
Please do not worry him trying to change directly or indirectly the working
plan he has. He has his ideas on frequencies, split and everything related.
In Spain we have a phrase "No me des consejos que ya se equivocarme solo"
Confirming my previous info, Gaby OD5NJ told me that he will relay
immediately to this reflector any info on precise times of operation.
See u on the band. Good luck specially for the people that a "new one " is a
matter "of life or death"
Jose EA3VY
From n1rj at pivot.net Sun Sep 28 08:28:06 2003
From: n1rj at pivot.net (Roger D Johnson)
Date: Sun Sep 28 08:26:07 2003
Subject: Topband: Astron noise
Message-ID: <3F76C5C6.9010701@pivot.net>
I did a pre-DX season noise finding survey of my house recently.
One strong source I thought was power line noise turned out to be
an Astron RS-12A power supply I have across a 12 volt battery used
to power the various DC items in the shack. The noise was very
high amplitude pulses every 16.66 ms ... especially strong on top
band. I notice some Astron models have .05 bypass caps to ground
across the DC outputs. Mine does not. I'm wondering if this is
noise from the rectifier diodes or some other source. Anyone have
any info???
73, Roger
From w8ji at contesting.com Sun Sep 28 09:31:30 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Sun Sep 28 09:22:26 2003
Subject: Topband: Open Wire Lines - Fact and Fiction
References:
<000901c3858b$5d906b80$a49ffea9@k9ay>
Message-ID: <001201c385bc$72d03760$188001d8@akorn.net>
I'm not sure what post Eric was referencing, because he didn't really quote
which post he was referring to.
My original post was 22 October 1998. I did make an error in a second post
on Aug 8, 2003 where I said:
"I had a 1500-foot open wire line of number 8 solid copper spaced just over
2
inches, and I impedance matched the line at both ends through broadband
transformers. I measured a power loss of 2% on 4 MHz, including the
transformers."
That should have been about 4% loss on 2 MHz, not 2% on 4MHz. We were
talking about 160, not 80 meters. Also since we are looking at this closely,
my line was 1400 feet long. Not 1500.
> In conclusion, I do not think an open wire (2) line with a loss of
> .005
> db/100' is possible in the HF ham bands. I would say that a long line like
> this would exhibit at least 1 db. total loss, from one 50ohm port to the
> other.
Not even close! My data was based on what I observed through measurements of
a real transmission line, and that is the final proof of any estimate.
I'm also puzzled by this:
<>
That is a disappointing comparison. Transformers for matching two ohms or
less to 50 ohms are considerably more difficult to construct with very low
loss than a 50 to 450 ohm transformer. Even so, I can do that in most HF PA
cases when I am not working with space and cost restraints!!
I can and have built 300kHz to 100MHz transformers for 450/50 ohm
applications with under .1dB loss over that entire range, and with an SWR
under 1.1:1 over that range. Transformer performance at higher Z from and
into non-reactive sources and terminations is nothing like the performance
in very low impedance applications. This is especially true if efficiency
is intentionally sacrificed for cost and space, and the source impedance is
very low and very reactive (as it is in most SS designs)!!!!
While Eric greatly overestimated feedline radiation, even Gary's more
optimistic estimate failed to consider line layout:
"The field intensity from a loop is proportional to the area enclosed
by the loop -- in dB, that's 20 log(Area1/Area2). Applied to the above
analogy, radiation from a 2-inch by 1500 foot loop is -67 dB relative to a
750 by 750 foot loop. -67 dB corresponds to a loss of 0.0000009 dB
(e.g. 0.2 mW out of 1 kW). That's not much radiation."
If conductors of the feedline are transposed at small fractions of a
wavelength along the line (perhaps by "twisting" the line), radiation from
each section cancels at distances large compared to the "twist distance".
My line was twisted every 20-40 feet, since it was primarily going to be a
160 and 80 meter line. Even the -67dB estimate is too high. On ten meters I
could hear "signals" listening to the dummy load terminated line. But then
the "twists" are a wavelength apart, and certainly no longer cancel farfield
signal response of the line! In that case I'm sure Gary's calculations are
correct.
The conductor resistance, according to my calculations, accounts for ALL of
the loss I measured. This makes sense to me, since there was no dielectric
to speak of. It also is a very well known effect that conductor resistance,
below upper UHF, accounts for the bulk of transmission line loss. At HF we
can pretty much ignore dielectric losses.
My measurements, made with good measurement protocol, were within reasonable
error of what theory predicts. 1400 foot of #8 copper in a 450 ohm line has
about the same loss as 100 feet of good quality 50 ohm RG-8 size coaxial
line on 2 MHz. It is far under 1dB, that is certain. If properly constructed
it also has negligible radiation. BE SURE to twist or transpose long
balanced lines at small fractional wavelength intervals!! This would include
long two-wire reversible Beverage antennas, especially with wide wire
spacing.
73 Tom
From petvet at adelphia.net Sun Sep 28 12:31:44 2003
From: petvet at adelphia.net (Scott Johns)
Date: Sun Sep 28 15:54:24 2003
Subject: Topband: Crossfire phasing
Message-ID: <000001c385d5$a26126b0$6401a8c0@hewlett5k1589j>
I would appreciate any journal/article references regarding the design
of crossfire phasing for receive arrays.
73, Scott W3TX
All outgoing e-mails checked by Norton Antivirus
From W8UVZ at voyager.net Sun Sep 28 18:34:05 2003
From: W8UVZ at voyager.net (George Taft)
Date: Sun Sep 28 17:48:47 2003
Subject: Topband: 3c0v
Message-ID: <3F7753CD.3E7F9A14@voyager.net>
I see a post to the DX summit re 3C0V today saying "40/80/160" on
Monday. Can anyone verify this info and know whether they meant Monday
AM, their time or Monday nite/Tuesday PM, their time??
Tks W8UVZ
From bernie at dailydx.com Mon Sep 29 00:11:51 2003
From: bernie at dailydx.com (Bernie McClenny, W3UR)
Date: Sun Sep 28 20:47:49 2003
Subject: Topband: 3c0v
In-Reply-To: <3F7753CD.3E7F9A14@voyager.net>
Message-ID: <023b01c38615$e6f66b10$6401a8c0@pavilion>
Yes George,
I spoke for a few moments today with Franz, DJ9ZB at 3C0V. He told me
the 40/80/160 meter antenna will be ready and installed Monday and that
they plan to be QRV Monday night (their time).
Bernie, W3UR
--
Bernie McClenny, W3UR
Editor of The Daily DX, The Weekly DX and How's DX.
http://www.dailydx.com
-----Original Message-----
From: topband-bounces@contesting.com
[mailto:topband-bounces@contesting.com] On Behalf Of George Taft
Sent: Sunday, September 28, 2003 21:34
To: Topband@contesting.com
Subject: Topband: 3c0v
I see a post to the DX summit re 3C0V today saying "40/80/160" on
Monday. Can anyone verify this info and know whether they meant Monday
AM, their time or Monday nite/Tuesday PM, their time??
Tks W8UVZ
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From brehm at ptitest.com Mon Sep 29 11:19:56 2003
From: brehm at ptitest.com (Brad Rehm)
Date: Mon Sep 29 13:03:15 2003
Subject: Topband: Astron noise
References: <3F76C5C6.9010701@pivot.net>
Message-ID: <004301c3869d$24498010$456fa8c0@3vlf901>
"...Astron RS-12A power supply...The noise was very
high amplitude pulses every 16.66 ms ... especially strong on top
band. 73, Roger"
_________________
Roger, the missing output capacitor probably has nothing to do with
this. Missing or not, the value is too small to have any effect at
this frequency. Also, the emissions are probably conducted back out
of the supply on the power cable.
Take a look at the MOV device across the incoming power leads and the
diode rectifiers. Check 'em by lifting one lead on each. 16 mS is
the 60 Hz power line frequency. Something is breaking down during one
half of the AC cycle. Most likely one of the full-wave rectifier
diodes.
73,
Brad, KV5V
From k9ay at k9ay.com Mon Sep 29 13:54:17 2003
From: k9ay at k9ay.com (K9AY)
Date: Mon Sep 29 14:59:27 2003
Subject: Topband: Open Wire Lines - Fact and Fiction
References:
<000901c3858b$5d906b80$a49ffea9@k9ay>
<001201c385bc$72d03760$188001d8@akorn.net>
Message-ID: <003901c386b3$0157b8e0$bd4efea9@k9ay>
My point was simply to show that the magnitude of this loss mechanism is
miniscule...
This tiny line loss due to radiation still exists if the line is twisted.
The twist simply achieves cancellation in the far field -- eliminating
signal ingress.
K9AY
_____
> While Eric greatly overestimated feedline radiation, even Gary's more
> optimistic estimate failed to consider line layout:
>
> "The field intensity from a loop is proportional to the area enclosed
> by the loop -- in dB, that's 20 log(Area1/Area2). Applied to the above
> analogy, radiation from a 2-inch by 1500 foot loop is -67 dB relative to a
> 750 by 750 foot loop. -67 dB corresponds to a loss of 0.0000009 dB
> (e.g. 0.2 mW out of 1 kW). That's not much radiation."
>
> If conductors of the feedline are transposed at small fractions of a
> wavelength along the line (perhaps by "twisting" the line), radiation from
> each section cancels at distances large compared to the "twist distance".
From ve3zi at yahoo.com Tue Sep 30 02:34:47 2003
From: ve3zi at yahoo.com (=?iso-8859-1?q?Roger=20Parsons?=)
Date: Mon Sep 29 20:35:06 2003
Subject: Topband: Open Wire Lines - Fact and Fiction
Message-ID: <20030930003448.78423.qmail@web14904.mail.yahoo.com>
I totally agree that line loss due to radiation is
normally miniscule. I was heavily involved in the
design of leaky feeder (radiating coax) cables when
the world was rather younger. Even when cables are
specifically designed to 'radiate', copper losses are
many orders greater than radiation losses, and
dielectric losses can usually be ignored. Balanced
lines can radiate rather more than coax when they are
unbalanced, or when the spacing becomes a significant
part of a wavelength (?BPL?) - intentionally or
otherwise - but the radiation losses are still tiny.
And just as an aside, even when coax cable has a 100%
outer conductor (ie solid copper) there will still be
an external field.
73 Roger
VE3ZI
________________________________________________________________________
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From mccapr at myrealbox.com Tue Sep 30 09:16:38 2003
From: mccapr at myrealbox.com (Jon Rudy-MCC Asia Peace Resource)
Date: Mon Sep 29 21:58:42 2003
Subject: Topband: DU9/N0NM on the air
Message-ID: <002e01c386f5$33300380$0200a8c0@jon>
Greetings from Davao.
I have completed the antenna work and am now regularly on 160. I will park and call on my usual frequency of 1828.3 going QSX up when activity is intense.
I have two rx antenna up. A delta loop pointed at 50 degrees covering SP to the US and some of South America SP. A pennant pointed 270 degrees (directly into the Delta loop apex so its very quiet) which covers EU and LP US. Tropical noise (QRN and QRM) continues to limit my RX.
I need to be gone some at the end of Oct. I would prefer not to set schedules but you can e-mail your call so I know who to listen for specifically. I will be on regularly at my sunset through continental US sunrise and my sunrise for EU and other parts of Asia west.
73...jon
================================
Jon Rudy
DU9/N0NM
Davao City, Mindanao, Philippines
Zone 27, Grid-PJ27, OC-130
EX: 3DA0CA, C91CO, ZS5UZ, A2/ZS5UZ
QSL via W4DR
E-mail: n0nm@arrl.net
=================================
From jsm at gulfislands.com Mon Sep 29 22:46:47 2003
From: jsm at gulfislands.com (Steve McDonald)
Date: Tue Sep 30 06:21:41 2003
Subject: Topband: Topband QRN
References: <007b01c3861b$d232f620$6711f4cc@jsm>
Message-ID: <000301c3870d$f1db1fa0$8d1179d1@jsm>
An annoying topband QRN problem for the past 2 months has finally been
traced to a neighbor's TV switching supply. It appears that the QRN source
is being radiated out and along the common powerline into the street where
the noise is e-probed and re-radiated by my 50' tower. My receive loop
couples into the field radiated by the tower all too effectively!
Is it possible to choke the QRN at the TV power cord? Would a large ferrite
J core wrapped with as many turns of the power cord be effective in
eliminating or attenuating this signal at its source?
Any hints appreciated.
Steve / VE7SL
From k9ay at k9ay.com Tue Sep 30 01:09:40 2003
From: k9ay at k9ay.com (K9AY)
Date: Tue Sep 30 06:21:45 2003
Subject: Topband: more feedline data
Message-ID: <003101c38711$1329b4c0$bd4efea9@k9ay>
I discovered an error in my calculations of basic resistive feedline loss, and I am not afraid to admit it! In the process of reviewing various references, I got the units wrong. Some formulas used frequency "f" in Hz, others in MHz. Murphy led to mix them up in my calculations. Here is a summary of the feedline loss in the recent discussion, checked and double-checked. The pertinent formulas can be found in "Reference Data for Radio Engineers," 6th ed, ITT/Howard W. Sams, 1982, pp 6-4 to 6-8, and 24-13.
At 2 MHz, skin depth on a copper conductor is 0.005 cm, or 2 mils. Thus, the entire conductor is not being utilized by the RF current flow and its effective resistance is greater than the DC resistance. The AC resistance is calculated as 0.011 ohms/foot, which must be doubled to include both conductors of the transmission line.
Keeping with the familiar loss per 100 ft. used for most feedline specifications, the 2.2 ohms resistance in 100 feet of 450-ohm feedline results in a loss of 0.02 dB/100 feet at 2 MHz, or 0.028 dB/100 feet at 4 MHz. 1400 feet of such a feedline would have a total loss of 0.28 dB at 2 MHz.
If the same wire was used at wider spacing in a 600 ohm line, the 2 MHz loss would be reduced to 0.015 dB/100 feet.
On this count, K8LV is correct -- the laws of physics insist that this is the lowest loss achievable. And Maxwell's work has held up pretty well over the years...
On the issues of feedline radiation and low-loss transmission line transformers, my earlier comments stand as-is.
With these numbers, the loss for 1400 feet of Tom's open-wire line should be in the range of 0.4 dB -- it would take 3" hardline or Heliax(R) and many $$$ to achieve this with coax.
73, Gary
K9AY
From df2py at t-online.de Tue Sep 30 06:21:00 2003
From: df2py at t-online.de (Dr .Wolf Ostwald)
Date: Tue Sep 30 06:21:47 2003
Subject: Topband: mag-field still sick !
Message-ID: <1A4CxB-1R67V20@fwd04.sul.t-online.com>
hello reflectees !
Observing the band in the last very much disturbed weeks and rite now in the more quiet range i found the following.Even with the A up in the 30ies USA stns made it thru from the midwest and from the eastern 5 area.Rite now the band had 2 days to recuperate from hi numbers and still is somewhat frustrating to lsn to. Only the very eastern seabord of the US makes it thru. At the same time 80m seems to be not as picky as topband is ( we all agree that topband must be a female structure - don`t we ? ).
I think its about time that Bob (NM7M )brings back some professional propagation explanation to us.
73 es gud dx de wolf
From f8bpn at wanadoo.fr Tue Sep 30 12:21:45 2003
From: f8bpn at wanadoo.fr (f8bpn)
Date: Tue Sep 30 08:27:53 2003
Subject: Topband: mag-field still sick !
References: <1A4CxB-1R67V20@fwd04.sul.t-online.com>
Message-ID: <001301c38745$0877fbc0$f5a83351@PHMARTIN>
Hi All, Hi Wolf!
What do you mean that way Wolf? Women are complicated to undestand....? Hi!
Sure the band is poor, so it doesn't give power enough to get up in the
night!
See you on the band
88 F8BPN
Mau
----- Original Message -----
From: "Dr .Wolf Ostwald"
To:
Sent: Tuesday, September 30, 2003 5:21 AM
Subject: Topband: mag-field still sick !
hello reflectees !
Observing the band in the last very much disturbed weeks and rite now in the
more quiet range i found the following.Even with the A up in the 30ies USA
stns made it thru from the midwest and from the eastern 5 area.Rite now the
band had 2 days to recuperate from hi numbers and still is somewhat
frustrating to lsn to. Only the very eastern seabord of the US makes it
thru. At the same time 80m seems to be not as picky as topband is ( we all
agree that topband must be a female structure - don`t we ? ).
I think its about time that Bob (NM7M )brings back some professional
propagation explanation to us.
73 es gud dx de wolf
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
From la2rz at online.no Tue Sep 30 15:05:24 2003
From: la2rz at online.no (La2rz)
Date: Tue Sep 30 08:27:55 2003
Subject: Topband: Topband QRN
References: <007b01c3861b$d232f620$6711f4cc@jsm>
<000301c3870d$f1db1fa0$8d1179d1@jsm>
Message-ID: <001001c3874b$21feceb0$0ba8a8c0@mikromekanikk.local>
Steve,
I had a simular problem some years back when working on 80 / 40 meters! this coincided with my neighbour buying a new
TV set, a Panasonic 29" 100hz. Strong birdies (59+) and some wide band noise also related.
After consulting with another ham who is a TV repair guy we found that the TV antenna coax was re-radiating. I popped on a large amount of div. ferrites from my junk box ( inner dia just over coax) about 60cms or so, this did the trick!
I did not check out 160 meters as this band was not of interest to me then but maybe there's noise on it. Would be a good idea to try this out on the power cord as well while your'e about it.
73's Dave LA2RZ
----- Original Message -----
From: "Steve McDonald"
To: <>
Sent: Tuesday, September 30, 2003 6:46 AM
Subject: Topband: Topband QRN
>
> An annoying topband QRN problem for the past 2 months has finally been
> traced to a neighbor's TV switching supply. It appears that the QRN source
> is being radiated out and along the common powerline into the street where
> the noise is e-probed and re-radiated by my 50' tower. My receive loop
> couples into the field radiated by the tower all too effectively!
> Is it possible to choke the QRN at the TV power cord? Would a large ferrite
> J core wrapped with as many turns of the power cord be effective in
> eliminating or attenuating this signal at its source?
>
> Any hints appreciated.
>
> Steve / VE7SL
>
> _______________________________________________
> Topband mailing list
> Topband@contesting.com
> http://lists.contesting.com/mailman/listinfo/topband
>
>
>
From bobnm7m at cnw.com Tue Sep 30 06:39:30 2003
From: bobnm7m at cnw.com (Robert Brown)
Date: Tue Sep 30 08:51:23 2003
Subject: Topband: mag-field still sick !
In-Reply-To: <1A4CxB-1R67V20@fwd04.sul.t-online.com>
Message-ID:
Wolf,
Thanks for the posting; it's good to hear from you again.
During times of high geomagnetic activity, the solar wind can distort
the high-latitude lines of force and carry E- and F-region electrons back
into the magneto-tail, adversely affecting DX propagagtion (e.g., DF to
W6) on long hops. Also, auroral activity increases ionospheric absorption
at lower altitudes in the auroral latitudes.
When the solar wind abates, E- and F-region ionization returns slowly to
the former equilibrium distribution, by upward diffusion of electrons and
photo-production during daylight. Because of density considerations,
there is a delay and the lower altitudes (and shorter DX hops) recover
first.
So paths into the polar caps suffer these effects while sub-auroral and
low-latitude paths are essentially immune.
73,
Bob, NM7M
From brehm at ptitest.com Tue Sep 30 10:06:17 2003
From: brehm at ptitest.com (Brad Rehm)
Date: Tue Sep 30 14:53:36 2003
Subject: Topband: Topband QRN
References: <007b01c3861b$d232f620$6711f4cc@jsm>
<000301c3870d$f1db1fa0$8d1179d1@jsm>
Message-ID: <001501c3875c$08669f30$456fa8c0@3vlf901>
"Is it possible to choke the QRN at the TV power cord? Would a large
ferrite
J core wrapped with as many turns of the power cord be effective in
eliminating or attenuating this signal at its source?
"Steve / VE7SL"
Steve,
It's worth a try. If the noise is in the lower HF bands and it is
conducted out of the set on the power leads, you'll want to find a
high-permeability ferrite torroid. One of the 2 1/2" o.d. cores that
Amidon sells should work. No. 77 material would be good. No. 33
would be better. If the problem is in the higher bands--15 to 10
meters--then, a more common No. 43 material core might do the trick.
Seven or eight turns on the core is all it takes.
If I had my choice of solutions, I'd use one of the power line filters
made by Corcom and others. The trouble with them is that you've got
to intercept the power cord as close to the receiver as possible to
make the really effective. It's also important to provide a ground
reference for these filters so that they have someplace to dump the
common-mode RF currents they've peeled off of the power leads.
Some of the better filters provide over 50 dB of attenuation of
signals below 30 MHz. That's much more than you can get by wrapping
the power cord around a torroidial core. Very few neighbors are
willing to let you install them properly, though.
73,
Brad, KV5V
From w8ji at contesting.com Tue Sep 30 08:46:36 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Tue Sep 30 14:53:39 2003
Subject: Topband: more feedline data
References: <003101c38711$1329b4c0$bd4efea9@k9ay>
Message-ID: <000201c38760$4a674d40$258001d8@akorn.net>
>On the issues of feedline radiation and low-loss transmission line
transformers, my earlier comments stand as-is.
>With these numbers, the loss for 1400 feet of Tom's open-wire line should
be in the range of 0.4 dB -- it would take 3" hardline or Heliax>(R) and
many $$$ to achieve this with coax.
That's right in line with what I measured...my measurement was about .35dB
loss.
As you pointed out, losses in matching and radiation are insignificant. With
the feeder properly installed, signal ingress is also insignificant so this
makes a very good feed system (if you can stand the maintenance).
73 Tom
From w8ji at contesting.com Tue Sep 30 09:54:52 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Tue Sep 30 14:53:42 2003
Subject: Topband: Topband QRN
References:
<007b01c3861b$d232f620$6711f4cc@jsm><000301c3870d$f1db1fa0$8d1179d1@jsm>
<001001c3874b$21feceb0$0ba8a8c0@mikromekanikk.local>
Message-ID: <000501c38760$4c341e00$258001d8@akorn.net>
I buy a cheap lightning protection unit that has CATV connectors on it, and
plug all the gear into that. I also route the TV antenna connection through
it.
That grounds the TV feedline to the power line ground.
If you add a couple .01uF UL/CSA/VDE rated line bypass caps from each side
of the power line to ground, it does more than ANY series RF choke would
ever do.
From jon.zaimes at dol.net Tue Sep 30 11:35:41 2003
From: jon.zaimes at dol.net (Jon Zaimes AA1K)
Date: Tue Sep 30 16:38:32 2003
Subject: Topband: DSL question
Message-ID: <5.2.0.9.0.20030930103535.00a874a0@127.0.0.1>
Nothing like the threat of BPL to rev up Verizon to get DSL in rural areas of Delaware. It's finally available here.
So my question....has anyone experienced any RFI problems with this?
73/Jon AA1K
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From w8ji at contesting.com Tue Sep 30 16:55:11 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Tue Sep 30 16:38:35 2003
Subject: Topband: Topband QRN
References:
<007b01c3861b$d232f620$6711f4cc@jsm><000301c3870d$f1db1fa0$8d1179d1@jsm>
<001501c3875c$08669f30$456fa8c0@3vlf901>
Message-ID: <00b901c3878c$c36bd0e0$3b8001d8@akorn.net>
Hi Brad and all,
My old cure here was a power plug with a built-in **suitable for line
bypass** .01uF cap between each conductor and the safety ground pin. (The
USA has a three wire system with a neutral, a safety ground, and a "hot"
wire). The CATV line is then grounded to the safety ground. This reduces
TVI, and interference back to the radio station. I found this much more
effective than anything else.
As I recall 73 material has about 30-80 ohms per linear inch of ferrite in
parallel with the conductor on 160 meters. It will also work well as an
absorber on much higher frequencies, certainly well beyond HF bands. One
problem with adding a core is the core flux density could be high, reducing
effective impedance, unless you have equal and opposing currents in the
winding.
Multiple turns through ONE core is much more effective than adding multiple
cores with only one pass through. Impedance goes up about by the square of
the turns increase. 4 turns through a 1" deep window has about the same
impedance as 16" long stack of cores with one pass through!!! Two passes
through are like having a 4" stack of cores.
You also do NOT need to use "fancy" winding techniques. It makes no
measurable difference at all below a few hundred MHz if you do that fancy
"winding flip" the Handbooks show. It will move stuff around a bit high in
the VHF area, but is not even significant up there!
All in all, it is **much** more effective to "connect" the TV power line to
the TV antenna lead through a coupling system like I described earlier than
to just slap a few beads at the problem. The reason is the TV set is
probably driving power lines as one leg of an "antenna" compared to the
Antenna Input of the TV.
Having done EMI certification, I know certification tests don't really watch
the antenna-to-powerline radiation mode nearly as much as they work to
prevent differential (push-pull) mode radiation down the power line,
although every product could be different in actual results. For this mode,
it is very difficult to get enough series impedance to eliminate problems
even with multiple turns, and almost impossible with a "single pass" winding
through a bead. A typical W2DU balun, with a string of beads a foot long,
only has several hundred ohms of Z on 160. On the other hand "shorting" the
radiation by RF connecting the power cord and antenna lead (with suitable
.01uF VDE/CE/UL rated capacitors) puts a few ohms load across the
unintentional noise generator, and greatly dampens any radiation.
Some TV's (ie plasma display TV's) radiate so much from the case that
nothing you do to input and output leads stops their QRM.
73 Tom
From brehm at ptitest.com Tue Sep 30 18:00:32 2003
From: brehm at ptitest.com (Brad Rehm)
Date: Tue Sep 30 17:39:17 2003
Subject: Topband: Topband QRN
References:
<007b01c3861b$d232f620$6711f4cc@jsm><000301c3870d$f1db1fa0$8d1179d1@jsm>
<001501c3875c$08669f30$456fa8c0@3vlf901>
<00b901c3878c$c36bd0e0$3b8001d8@akorn.net>
Message-ID: <004c01c3879e$456d2830$456fa8c0@3vlf901>
Hi Tom, et al.!
Some good comments about the problem. Let me add a few more:
"My old cure here was a power plug with a built-in **suitable for line
bypass** .01uF cap between each conductor and the safety ground pin.
(The
USA has a three wire system with a neutral, a safety ground, and a
"hot"
wire). The CATV line is then grounded to the safety ground. This
reduces
TVI, and interference back to the radio station. I found this much
more
effective than anything else."
You bet! Steve would have to build a fixture to hold the capacitors
to the back of the plug, though. TV sets usually have 2-wire power
leads, so the "fixture" at the wall plug would have to decouple the RF
to the safety ground. He also has to be sure to use X2- or Y2-type
capacitors that are UL approved for across-the-line applications.
They're also called "Suppression Capacitors." I know you mentioned
this, but I want to stress the point.
Here's a thought about using capacitors in this way: We assume that
the caps route the RF to a low-impedance load (the safety ground
system) and that the efficiency of the driver (the TV set) will go
down because its impedance is relatively high. The mismatch results
in reduced radiation from the AC wiring in the house. This works if
the impedance of the Safety Ground wiring is low. If it isn't, it
could and probably will radiate as effectively as the hot and neutral
wires did before the capacitors were added.
This could happen if the RF conducted on the power cord is
common-mode. Both line and neutral can "drive" Safety Ground. And
this is the reason Steve should be prepared to try ferrites too. They
dissipate the RF instead of re-directing it.
"One problem with adding a core is the core flux density could be
high, reducing
effective impedance, unless you have equal and opposing currents in
the winding."
The 60 Hz AC currents are opposing in the power cord, so they wouldn't
affect the core. The strongest conducted RF emissions--the kind we're
concerned about here--are usually in the hundreds of microampere
range. This is well below what it would take to saturate a 2 1/2" OD
core.
"Having done EMI certification, I know certification tests don't
really watch
the antenna-to-powerline radiation mode nearly as much as they work to
prevent differential (push-pull) mode radiation down the power
line...."
Yes. The problem, so far as hams are concerned, is that Radiated
Emissions measurements are all made above 30 MHz. Labs are only
required to measure Conducted Emissions from 150 kHz to 30 MHz, and
the ANSI C63.4 CE test setup is designed to prevent measuring
displacement currents between the power and antenna leads.
Moral: If you're a ham, take a transceiver with you when you buy your
next TV, VCR, or DVD player. Listen for emissions. Then, turn the
transmitter on and see how it affects the gadget. (There's usually
some reciprocity between emissions and immunity in electronic
devices.) A 5-Watt 2 meter HT works fine for this. It's interesting
to be able to shut down all but one or two VCRs on a shelf of ten at
Sears. I always buy one of the ones that my HT can't get to. They're
often the least expensive, and I have very little trouble with the
ones I've selected in this way.
"Some TV's (ie plasma display TV's) radiate so much from the case that
nothing you do to input and output leads stops their QRM."
I've tried the HT trick on some of these. You can imagine how quickly
that gets the salesman's attention. High susceptibility is usually
related to high emissions at some frequency or another.
73,
Brad, KV5V
From w8ji at contesting.com Tue Sep 30 21:37:26 2003
From: w8ji at contesting.com (Tom Rauch)
Date: Tue Sep 30 21:24:05 2003
Subject: Topband: Topband QRN
References:
<007b01c3861b$d232f620$6711f4cc@jsm><000301c3870d$f1db1fa0$8d1179d1@jsm><001501c3875c$08669f30$456fa8c0@3vlf901><00b901c3878c$c36bd0e0$3b8001d8@akorn.net>
<004c01c3879e$456d2830$456fa8c0@3vlf901>
Message-ID: <002c01c387b4$31ad2640$3e8001d8@akorn.net>
> Here's a thought about using capacitors in this way: We assume that
> the caps route the RF to a low-impedance load (the safety ground
> system) and that the efficiency of the driver (the TV set) will go
> down because its impedance is relatively high. The mismatch results
> in reduced radiation from the AC wiring in the house. This works if
> the impedance of the Safety Ground wiring is low. If it isn't, it
> could and probably will radiate as effectively as the hot and neutral
> wires did before the capacitors were added.
The primary enhancement of radiation occurs because the TV set (or SMPS in a
computer) has something to work "against". In computers, it's normally the
modem connection to the telco lines or other large wiring systems that act
like a counterpoise. Then the PS pumps the AC line, the AC line filter as
shipped from the factory is normally some rather large effective capacitors
from side to side of the line, but NOTHING to the chassis. So there is
substantial bypassing from conductor to conductor of the power line, but not
much if anythingto the chassis. The telephone line (in a computer) or the
antenna lead in a TV is bypassed to the chassis, so you have an instant
ground system for the power supply common mode to "push against".
Think of it as a little BPL system, with the telco or CATV lines one
conductor and the power lines another.
Connecting the Telco ground or antenna ground to NEW bypass capacitors on
the power line prevents the wonderful antenna and widely spaced
"counterpoise" from being at different potentials for RF.
The reason I stressed the safety ground is the .01 capacitors pass some
small current, and can "bite" the user if they are not grounded. This is
actually why manufacturers won't use such bypasses, it makes the case "hot"
with a very tiny current at 60 volts RMS. The safety ground connection
prevents that from happening, and prevents high current if a capacitor
shorts (extremely unlikely if you use the proper part, but still possible).
Its sole function is safety, otherwise it would not be needed.
> This could happen if the RF conducted on the power cord is
> common-mode. Both line and neutral can "drive" Safety Ground. And
> this is the reason Steve should be prepared to try ferrites too. They
> dissipate the RF instead of re-directing it.
Virtually all SMPS already have ferrites inside specifically for that
function. The reason they don't work well in every case is the required low
shunt impedance is missing. The manufacturer generally bypasses from power
line supply wire-to-wire, not from supply wire to chassis!
I'm not opposing ferrite cores, just reminding people that a choke doesn't
do much unless the impedance of the coke is very high compared to the shunt
impedance, and also a snap on bead has very little impedance with "one wire
pass". With little or no shunt capacitance, you don't have much of a
pi-filter!!! I have always found adding capacitors and grounding does far
more than adding chokes, mostly because most PS already have adequate chokes
inside...they simply lack bypass capacitors to the chassis.
By the way, the capacitors MUST be in a flame proof housing and you must use
this in a system with a safety ground. That's why I suggest buying a surge
protector that allows power line, CATV, and telephone lines to pass through.
I just get inside and add suitable .01 bypass caps on the power line and
telco lines. The CATV lines are already grounded to the neutral inside! I
replace telco line fuses with small molded 470uH chokes. An additional
benefit is all this work keeps RF out of the device, and greatly improves
lightning protection.
Few people will object to installing something that looks professional and
has improved lightning protection.
73 Tom