Topband: Topband Digest, Vol 109, Issue 1
wa3mej at comcast.net
wa3mej at comcast.net
Sun Jan 1 10:54:10 PST 2012
Jose:
I have been a ham for a long while having seen the transition from tube to transistorized rigs. Although I have an amp the only time I find it necessary is when working DX on 160 much of the rest of the time I do not use the amp. Phase noise is caused by the synthesizers in the newer solid state transceivers not the digital modes. HOwever if your not tech savy enough to know how to tune the radio to properly run the digital mode in use, well then all bets are off. I can almost promise you a very wide noisy signal that may or may not spread out much of the band but then this is no different than any other mode .
ALL digital modes must be tuned so that no ALC is drawn during transmit. While I have the capability to run higher power on digital modes I have never found it necessary even when working the W3 to JA or 9M2 paths.. I have never run more than 50 watts on digital (the point at which my 756 Pro II starts to show ALC). The rules say that we should run no more power than necessary and to do so means we are being poor radio neighbors.
Why cant we share the band the digital signals use up only a fraction of the 40+ Khz used for CW and they are not present during contests (I mean they are not crazy ya know) Many countries do not go above 1900Khz and lets face it the bottom end between 1800 and 1810 is for the most part untouched except during contests.
By the way W3DF lives less than 5 miles and W3KL lives about 8 miles and when they are running legal limit on CW they do not bother me at 5KHz away nor do I bother them.. I do not see this changing even if I were running digital modes other than CW.
CW is a lot of fun. I am an ex Navy radioman and love it, having gone through high speed CW school (not that you would know it now). I am also a veteral with a service connected disability.. you see I am hearing impared with some maj or tinitus (ringing in the ears). Some days it is so bad that I cant work CW and go to the digital modes, it has been a life saver and helped me keep my sanity, although if you talk to my wife she might disagree with this assessment when she looks at my antenna concoctions!
In any event...
Happy New Year hope to talk to you on the band some day
Jim WA3MEJ
Message: 6
Date: Sat, 31 Dec 2011 23:27:55 -0500
From: "n4is" < n4is at comcast.net >
Subject: Re: Topband: 160M JT65HF
To: < jim at audiosystemsgroup.com >, < topband at contesting.com >
Message-ID: <000301ccc83d$bc7fbcb0$357f3610$@comcast.net>
Content-Type: text/plain; charset="us-ascii"
Happy New Year to all
Jim, I'd love to have you as a neighbor. You know how to set up a station
for best performance. I had experience with some stations in my area that
wants to get long DX increasing power without knowing how to do it. I was
able to hear the guy on several different frequencies and plenty of phase
noise. Digital modes using AF can be very noisy if you don't know what you
are doing.
I have a DDR SDR and I can see the noise across the band on the water fall
associated with the shift on the digital signal.
Why not allocate digital mode above 1900 KHz?
I know JT65, FSK441, etc. very well. I was very active on MS on 2 and 6m
when we transitioned from fast speed cw to JT modes 10 years ago. Also I did
EME CW and some JT65 on 144 MHz.
Regards
Jose Carlos
N4IS
------------------------------
Message: 7
Date: Sat, 31 Dec 2011 23:48:47 -0500
From: "Joe Subich, W4TV" < lists at subich.com >
Subject: Re: Topband: 160M JT65HF
To: topband at contesting.com
Message-ID: < 4EFFE5AF.4020302 at subich.com >
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> Why not allocate digital mode above 1900 KHz?
Because 1900 and up is not available in many areas of the world.
Although I'm not happy with TJ65 at 1838 - it's far better than
the over driven SSB, ESSB and AM that was the norm between 1830
and 1850 a few years ago (and still exists in some areas).
Of course 600 Watt JT65 is nothing more than an alligator ...
it causes a tremendous amount of QRM from all the stations calling
that the high power station can't hear. When someone on the East
Coast (or Caribbean) hear a west coast station they don't bother to
think that the west coast (or Pacific) station is running 10-12 dB
more power than "normal."
I don't think that anyone on 160 wants a JT65 "arms race" where 1500 W
outputs become normal. Not only will the perception of interference to
other operations become worse, the very strong signals will cause AGC
issues that will make copying the weaker signals much more difficult
for everybody.
73,
... Joe, W4TV
----- Original Message -----
From: topband-request at contesting.com
To: topband at contesting.com
Sent: Sunday, January 1, 2012 3:22:22 AM
Subject: Topband Digest, Vol 109, Issue 1
Send Topband mailing list submissions to
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When replying, please edit your Subject line so it is more specific
than "Re: Contents of Topband digest..."
Today's Topics:
1. More Inv-L matching issues.... (Dan Bookwalter)
2. Re: K2AV 160m Folded Counterpoise (FCP), parts and winding
for isolation transformer. (James Rodenkirch)
3. More Inv-L matching issues.... BIGGER ISSUE (Dan Bookwalter)
4. Re: More Inv-L matching issues.... BIGGER ISSUE (Paul Dulaff)
5. Re: 160M JT65HF (Jim Brown)
6. Re: 160M JT65HF (n4is)
7. Re: 160M JT65HF (Joe Subich, W4TV)
8. Re: K2AV 160m Folded Counterpoise (FCP), parts and winding
for isolation transformer. (Guy Olinger K2AV)
----------------------------------------------------------------------
Message: 1
Date: Sat, 31 Dec 2011 12:41:13 -0800 (PST)
From: Dan Bookwalter <n8dcj at yahoo.com>
Subject: Topband: More Inv-L matching issues....
To: "topband at contesting.com" <topband at contesting.com>
Message-ID:
<1325364073.55926.YahooMailNeo at web34405.mail.mud.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1
well about a month ago i put up my Inv-L , it is now ~165ft , I have an air variable in series , and 12 radials anywhere from 150-250ft long ( going out to add more as soon as i am done typing this). my SWR wasn't too bad maybe 1.7:1 at the best. Two nights ago I added an amplifier to the mix ~700w , well to make a long story short I smoked one of the relays in my RCS-10 , I am now not too sure what to do , I don't want to keep blowing out relays in the RCS-10.
I had several responses back then regarding matching etc... , but , in my haste i seem to have deleted them :-(?
so here i am again asking for advice...
any help greatly appreciated?
Dan N8DCJ
------------------------------
Message: 2
Date: Sat, 31 Dec 2011 14:14:26 -0700
From: James Rodenkirch <rodenkirch_llc at msn.com>
Subject: Re: Topband: K2AV 160m Folded Counterpoise (FCP), parts and
winding for isolation transformer.
To: <olinger at bellsouth.net>, <rgarrett5 at comcast.net>,
<w0uce at nc.rr.com>, <topband at contesting.com>, <press at thewireman.com>
Message-ID: <SNT137-W45290BA30685E2DE072AB0F0930 at phx.gbl>
Content-Type: text/plain; charset="iso-8859-1"
Would that FCP work with my 43' vertical, three 25' top loading wires that drop at a 45 degree angle (patterned after the NORD antenna model) and have a 160 meter loading coil that I put in series with an auto tuner at the base???
Using a less than complete counterpoise "field" - about 40 radials, not symmetrical and not even in lengths. Max power is 20 watts out of a Ten Tec Argonaut V 516 but run QRP most of the time.
Thank you, in advance, for comments, suggestions or escape plans!
72, Jim Rodenkirch, K9JWV
> Date: Fri, 30 Dec 2011 20:50:48 -0500
> From: olinger at bellsouth.net
> To: rgarrett5 at comcast.net; w0uce at nc.rr.com; topband at contesting.com; press at thewireman.com
> Subject: Topband: K2AV 160m Folded Counterpoise (FCP), parts and winding for isolation transformer.
>
> As requested.
>
> Parts:
>
> http://thewireman.com/wirep.html#631 #635 Double polyimide insulated
> #14 AWG, 15 feet.
>
> https://www.amidoncorp.com/categories/15 #12 AWG standard wall teflon
> tubing, 15 feet.
>
> https://www.amidoncorp.com/items/26 T300A-2 #2 material powdered iron
> toroid.
>
> You can also use Micrometals T300-2D, or a PAIR of Micrometals T300-2
> stacked and taped together with fiberglass tape, which are the same as
> Amidon T300A-2. You can often find the Micrometals cores on eBay.
>
> Note: The core material, bifilar winding turn count, and core dimensions
> are chosen to facilitate a "simple" 160 installation that has approximately
> 1/4 wave wire, a toroid wound balun-sized isolation transformer feeding the
> coax, and a folded counterpoise attached, that delivers an impedance that
> is close enough to 50 ohms resistive to reasonably use regular coax as a
> feed. If you change the turn count, or the core material, or core
> dimensions, this balance for the "simple solution" is defeated, and the
> conditions which were tested in our two year research period no longer
> apply. You might substitute configurations which we put up ourselves,
> tested, and specifically rejected for cause. Like burned it up, was lossy,
> wouldn't stay tuned, was worse than the original antenna, etc, etc
>
> You can't use a stack of smaller diameter cores with the same total of A
> sub L numbers because you can't get the required 20 bifilar turns on the
> inside diameter of the smaller cores. 20 turns fills up the inside diameter
> of the T300x-x form factor. If you don't use 20 turns, then you will get
> less inductive reactance to cancel the FCP's capacitive reactance for the
> simple installation and need more wire in the radiator to compensate.
> Dropping only one turn on the core will add 12 or 13 feet to the "pruned"
> length for resonance you would have had otherwise.
>
> The #2 powdered iron core material has been very carefully chosen for 1.8
> MHz QRP and QRO, drawing on advice and published work by W2FMI. Do not
> substitute ferrite or other powdered iron materials. #2 powdered iron cores
> are always painted red and easily identified. A core without paint or a
> different color will not work.
>
>
> Winding:
>
> First, have a look on W0UCE's site for a good picture of one of these
> correctly done . (Pix worth 1000 words and all that...)
> http://www.w0uce.net/K2AVantennas.html
> Scroll down for the pictures. Note the appearance of the bifilar pair when
> done right. Think of the bifilar pair as an exotic "zip cord". You will
> be winding the PAIR as if you were winding with zip cord.
>
> The professionally wound version from Balun Designs with enclosure and
> hardware can be seen at:
> http://www.balundesigns.com/servlet/the-108/1-cln-1-High-Isolation-Balun/Detail
>
>
>
> Cut wire and tubing in half and slip the wire inside the tubing to create a
> pair of parallel 7.5 feet teflon-sleeved wires. Some find it easier to
> handle the wires in winding if you tape them together.
>
> Tightly wind twenty bifilar turns around the core. This will use all the
> space in the inner diameter. Keep the bifilar pair turns separate and
> uniformly spaced on the outside. ALL the wires should be laying flat on
> the toroid, with NO twist flips where the wires do an "over-under".
>
> IMPORTANT: When properly connected there is NO connection between the
> antenna/FCP side and the coax side. CAUTION: If you get that WRONG when
> you hook it up, you will STILL be able to hear on it, but the system won't
> work right and you will loose valuable dB's.
>
> !!! VERIFY THE SEPARATION !!! with an ohmmeter BEFORE you start pruning the
> antenna wire or hurling electronic curses at dog, family, neighbors, or me.
>
> To wind one of these for a 16+16 version FCP for 80 meters, and you are
> doing the "simple" version with 67 feet or so radiator above the FCP,
> evenly space *fifteen* bifilar turns around the toroid.
>
> 73, and I'm looking forward to a lot more 160 QSO's in the contests,
>
> Guy K2AV
>
>
> On Sat, Dec 10, 2011 at 1:38 PM, Bob Garrett <rgarrett5 at comcast.net> wrote:
>
> > Hello Guy,
> >
> > When the dust settles, will you post a list of parts and sources so we can
> > duplicate this antenna and the unique matching network? 73, Bob K3UL
> >
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
------------------------------
Message: 3
Date: Sat, 31 Dec 2011 14:34:09 -0800 (PST)
From: Dan Bookwalter <n8dcj at yahoo.com>
Subject: Topband: More Inv-L matching issues.... BIGGER ISSUE
To: "topband at contesting.com" <topband at contesting.com>
Message-ID:
<1325370849.12907.YahooMailNeo at web34407.mail.mud.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1
Ok...
I went and added 9 more radials the SWR is now at 1.2:1 after some adjusting of the air variable....
well , i decided to see how the amp (Alpha 374A) loaded into the antenna , I keyed down with maybe 500 watts and everything went dead again in less that 1 second. So it now appears that I have smoked another relay in the RCS-10 .
One thing about this configuration is that the base of the antenna is about 16" from the RCS-10 , is this too close ? I can probably move it so that it is about 4' away if that is the issue.... I cant afford to keep destroying relays and such....
thoughts ?
Dan N8DCJ
________________________________
-----Original Message-----
From: topband-bounces at contesting.com [mailto:topband-bounces at contesting.com]
On Behalf Of Dan Bookwalter
Sent: Saturday, December 31, 2011 2:41 PM
To: topband at contesting.com
Subject: Topband: More Inv-L matching issues....
well about a month ago i put up my Inv-L , it is now ~165ft , I have an air
variable in series , and 12 radials anywhere from 150-250ft long ( going out
to add more as soon as i am done typing this). my SWR wasn't too bad maybe
1.7:1 at the best. Two nights ago I added an amplifier to the mix ~700w ,
well to make a long story short I smoked one of the relays in my RCS-10 , I
am now not too sure what to do , I don't want to keep blowing out relays in
the RCS-10.
I had several responses back then regarding matching etc... , but , in my
haste i seem to have deleted them :-(?
so here i am again asking for advice...
any help greatly appreciated?
Dan N8DCJ
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2012.0.1901 / Virus Database: 2109/4714 - Release Date: 12/31/11
------------------------------
Message: 4
Date: Sat, 31 Dec 2011 20:21:44 -0500 (EST)
From: Paul Dulaff <pdulaff at embarqmail.com>
Subject: Re: Topband: More Inv-L matching issues.... BIGGER ISSUE
To: Dan Bookwalter <N8DCJ at YAHOO.COM>
Cc: topband at contesting.com
Message-ID:
<762340724.821141.1325380904314.JavaMail.root at md23.embarq.synacor.com>
Content-Type: text/plain; charset=utf-8
Dan
A couple of thoughts...
When transmitting, is the RCS-10 antenna switch inadvertantly changing (switching) antennas (ports) during the transition from receive to transmit, possibly RF getting into the switching circuit causing this ? Do you lose the 12VDC to the switch when changing from receive to transmit ? Are you trying to support semi-break-in with the RCS-10 ?
The ratings on this switch are fairly good. 16 amps, 1200 volts. I would think that it would need to be feeding an open or a short to fail this quickly at this power level or switching at full power.
Paul - WB2NMI
----- Original Message -----
From: Dan Bookwalter <n8dcj at yahoo.com>
To: topband at contesting.com
Sent: Sat, 31 Dec 2011 17:34:09 -0500 (EST)
Subject: Topband: More Inv-L matching issues.... BIGGER ISSUE
Ok...
I went and added 9 more radials the SWR is now at 1.2:1 after some adjusting of the air variable....
well , i decided to see how the amp (Alpha 374A) loaded into the antenna , I keyed down with maybe 500 watts and everything went dead again in less that 1 second. So it now appears that I have smoked another relay in the RCS-10 .
One thing about this configuration is that the base of the antenna is about 16" from the RCS-10 , is this too close ? I can probably move it so that it is about 4' away if that is the issue.... I cant afford to keep destroying relays and such....
thoughts ?
Dan N8DCJ
________________________________
-----Original Message-----
From: topband-bounces at contesting.com [mailto:topband-bounces at contesting.com]
On Behalf Of Dan Bookwalter
Sent: Saturday, December 31, 2011 2:41 PM
To: topband at contesting.com
Subject: Topband: More Inv-L matching issues....
well about a month ago i put up my Inv-L , it is now ~165ft , I have an air
variable in series , and 12 radials anywhere from 150-250ft long ( going out
to add more as soon as i am done typing this). my SWR wasn't too bad maybe
1.7:1 at the best. Two nights ago I added an amplifier to the mix ~700w ,
well to make a long story short I smoked one of the relays in my RCS-10 , I
am now not too sure what to do , I don't want to keep blowing out relays in
the RCS-10.
I had several responses back then regarding matching etc... , but , in my
haste i seem to have deleted them :-(?
so here i am again asking for advice...
any help greatly appreciated?
Dan N8DCJ
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2012.0.1901 / Virus Database: 2109/4714 - Release Date: 12/31/11
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
------------------------------
Message: 5
Date: Sat, 31 Dec 2011 19:01:52 -0800
From: Jim Brown <jim at audiosystemsgroup.com>
Subject: Re: Topband: 160M JT65HF
To: topband at contesting.com
Message-ID: <4EFFCCA0.9040002 at audiosystemsgroup.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
On 12/31/2011 11:15 AM, Darl DEEDS wrote:
> I was under the impression that JT65 was a weak signal mode. 600 watts seems
> a lot for that. Is that a normal power level for that? I was hoping to work
> it without an amplifier.
If you only want to work W6 to W1, or even W6 to JA, yes. But if you
want to work W6 to EU on 160, which is a very difficult path, the
additional 12-18 dB that an amp provides can make the difference. And
EU is why I'm doing it.
73, Jim K9YC
------------------------------
Message: 6
Date: Sat, 31 Dec 2011 23:27:55 -0500
From: "n4is" <n4is at comcast.net>
Subject: Re: Topband: 160M JT65HF
To: <jim at audiosystemsgroup.com>, <topband at contesting.com>
Message-ID: <000301ccc83d$bc7fbcb0$357f3610$@comcast.net>
Content-Type: text/plain; charset="us-ascii"
Happy New Year to all
Jim, I'd love to have you as a neighbor. You know how to set up a station
for best performance. I had experience with some stations in my area that
wants to get long DX increasing power without knowing how to do it. I was
able to hear the guy on several different frequencies and plenty of phase
noise. Digital modes using AF can be very noisy if you don't know what you
are doing.
I have a DDR SDR and I can see the noise across the band on the water fall
associated with the shift on the digital signal.
Why not allocate digital mode above 1900 KHz?
I know JT65, FSK441, etc. very well. I was very active on MS on 2 and 6m
when we transitioned from fast speed cw to JT modes 10 years ago. Also I did
EME CW and some JT65 on 144 MHz.
Regards
Jose Carlos
N4IS
------------------------------
Message: 7
Date: Sat, 31 Dec 2011 23:48:47 -0500
From: "Joe Subich, W4TV" <lists at subich.com>
Subject: Re: Topband: 160M JT65HF
To: topband at contesting.com
Message-ID: <4EFFE5AF.4020302 at subich.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> Why not allocate digital mode above 1900 KHz?
Because 1900 and up is not available in many areas of the world.
Although I'm not happy with TJ65 at 1838 - it's far better than
the over driven SSB, ESSB and AM that was the norm between 1830
and 1850 a few years ago (and still exists in some areas).
Of course 600 Watt JT65 is nothing more than an alligator ...
it causes a tremendous amount of QRM from all the stations calling
that the high power station can't hear. When someone on the East
Coast (or Caribbean) hear a west coast station they don't bother to
think that the west coast (or Pacific) station is running 10-12 dB
more power than "normal."
I don't think that anyone on 160 wants a JT65 "arms race" where 1500 W
outputs become normal. Not only will the perception of interference to
other operations become worse, the very strong signals will cause AGC
issues that will make copying the weaker signals much more difficult
for everybody.
73,
... Joe, W4TV
On 12/31/2011 11:27 PM, n4is wrote:
> Happy New Year to all
>
> Jim, I'd love to have you as a neighbor. You know how to set up a station
> for best performance. I had experience with some stations in my area that
> wants to get long DX increasing power without knowing how to do it. I was
> able to hear the guy on several different frequencies and plenty of phase
> noise. Digital modes using AF can be very noisy if you don't know what you
> are doing.
> I have a DDR SDR and I can see the noise across the band on the water fall
> associated with the shift on the digital signal.
>
> Why not allocate digital mode above 1900 KHz?
>
> I know JT65, FSK441, etc. very well. I was very active on MS on 2 and 6m
> when we transitioned from fast speed cw to JT modes 10 years ago. Also I did
> EME CW and some JT65 on 144 MHz.
>
> Regards
> Jose Carlos
> N4IS
>
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
------------------------------
Message: 8
Date: Sun, 1 Jan 2012 03:22:17 -0500
From: Guy Olinger K2AV <olinger at bellsouth.net>
Subject: Re: Topband: K2AV 160m Folded Counterpoise (FCP), parts and
winding for isolation transformer.
To: James Rodenkirch <rodenkirch_llc at msn.com>
Cc: topband at contesting.com
Message-ID:
<CANckpc3Z2LWLd_r_U9qPACBHLiEWady1QzVkCLVCDERgzqyAWQ at mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Just remember that an FCP is a SINGLE BAND device. If you use a 160 FCP on
80 meters, the field cancellation will not occur and it will be lossy.
Second, the gorilla in the room for QRP is eliminating loss. Wind the 160m
isolation transformer (ISOT) as specified or get the Balun Designs
commercial duplicate. Put the auto tuner right at the transformer, and it
will work. You will not need the loading coil if the tuner is at the ISOT.
You can put any kind of antenna on the other wire connection on the ISOT.
You just need to tune it right at the coax connection of the ISOT. If you
put more than 2-6 feet of coax between ISOT and autotuner you may start
running up losses. Put the coax to the shack on the tuned output side of
the autotuner so the shack coax is matched and losses are minimum.
An antenna like the one you describe has a very low radiation resistance on
160, therefore the current is very high in whatever counterpoise is in use.
A radial system used with this antenna that is NOT dense, AND uniform
length and spacing, will be that much more lossy and the FCP will make a
large difference. Critical with QRP. It is entirely possible that a
miscellaneous radial collection could reduce your 5 watts to a half watt.
For QRP, do the radials right, or use a counterpoise specifically designed
to minimize loss.
73, Guy.
On Sat, Dec 31, 2011 at 4:14 PM, James Rodenkirch <rodenkirch_llc at msn.com>wrote:
> Would that FCP work with my 43' vertical, three 25' top loading wires
> that drop at a 45 degree angle (patterned after the NORD antenna model) and
> have a 160 meter loading coil that I put in series with an auto tuner at
> the base???
>
> Using a less than complete counterpoise "field" - about 40 radials, not
> symmetrical and not even in lengths. Max power is 20 watts out of a Ten
> Tec Argonaut V 516 but run QRP most of the time.
>
> Thank you, in advance, for comments, suggestions or escape plans!
>
> 72, Jim Rodenkirch, K9JWV
>
>
> > Date: Fri, 30 Dec 2011 20:50:48 -0500
> > From: olinger at bellsouth.net
> > To: rgarrett5 at comcast.net; w0uce at nc.rr.com; topband at contesting.com;
> press at thewireman.com
> > Subject: Topband: K2AV 160m Folded Counterpoise (FCP), parts and winding
> for isolation transformer.
>
> >
> > As requested.
> >
> > Parts:
> >
> > http://thewireman.com/wirep.html#631 #635 Double polyimide insulated
> > #14 AWG, 15 feet.
> >
> > https://www.amidoncorp.com/categories/15 #12 AWG standard wall teflon
> > tubing, 15 feet.
> >
> > https://www.amidoncorp.com/items/26 T300A-2 #2 material powdered iron
> > toroid.
> >
> > You can also use Micrometals T300-2D, or a PAIR of Micrometals T300-2
> > stacked and taped together with fiberglass tape, which are the same as
> > Amidon T300A-2. You can often find the Micrometals cores on eBay.
> >
> > Note: The core material, bifilar winding turn count, and core dimensions
> > are chosen to facilitate a "simple" 160 installation that has
> approximately
> > 1/4 wave wire, a toroid wound balun-sized isolation transformer feeding
> the
> > coax, and a folded counterpoise attached, that delivers an impedance that
> > is close enough to 50 ohms resistive to reasonably use regular coax as a
> > feed. If you change the turn count, or the core material, or core
> > dimensions, this balance for the "simple solution" is defeated, and the
> > conditions which were tested in our two year research period no longer
> > apply. You might substitute configurations which we put up ourselves,
> > tested, and specifically rejected for cause. Like burned it up, was
> lossy,
> > wouldn't stay tuned, was worse than the original antenna, etc, etc
> >
> > You can't use a stack of smaller diameter cores with the same total of A
> > sub L numbers because you can't get the required 20 bifilar turns on the
> > inside diameter of the smaller cores. 20 turns fills up the inside
> diameter
> > of the T300x-x form factor. If you don't use 20 turns, then you will get
> > less inductive reactance to cancel the FCP's capacitive reactance for the
> > simple installation and need more wire in the radiator to compensate.
> > Dropping only one turn on the core will add 12 or 13 feet to the "pruned"
> > length for resonance you would have had otherwise.
> >
> > The #2 powdered iron core material has been very carefully chosen for 1.8
> > MHz QRP and QRO, drawing on advice and published work by W2FMI. Do not
> > substitute ferrite or other powdered iron materials. #2 powdered iron
> cores
> > are always painted red and easily identified. A core without paint or a
> > different color will not work.
> >
> >
> > Winding:
> >
> > First, have a look on W0UCE's site for a good picture of one of these
> > correctly done . (Pix worth 1000 words and all that...)
> > http://www.w0uce.net/K2AVantennas.html
> > Scroll down for the pictures. Note the appearance of the bifilar pair
> when
> > done right. Think of the bifilar pair as an exotic "zip cord". You will
> > be winding the PAIR as if you were winding with zip cord.
> >
> > The professionally wound version from Balun Designs with enclosure and
> > hardware can be seen at:
> >
> http://www.balundesigns.com/servlet/the-108/1-cln-1-High-Isolation-Balun/Detail
> >
> >
> >
> > Cut wire and tubing in half and slip the wire inside the tubing to
> create a
> > pair of parallel 7.5 feet teflon-sleeved wires. Some find it easier to
> > handle the wires in winding if you tape them together.
> >
> > Tightly wind twenty bifilar turns around the core. This will use all the
> > space in the inner diameter. Keep the bifilar pair turns separate and
> > uniformly spaced on the outside. ALL the wires should be laying flat on
> > the toroid, with NO twist flips where the wires do an "over-under".
> >
> > IMPORTANT: When properly connected there is NO connection between the
> > antenna/FCP side and the coax side. CAUTION: If you get that WRONG when
> > you hook it up, you will STILL be able to hear on it, but the system
> won't
> > work right and you will loose valuable dB's.
> >
> > !!! VERIFY THE SEPARATION !!! with an ohmmeter BEFORE you start pruning
> the
> > antenna wire or hurling electronic curses at dog, family, neighbors, or
> me.
> >
> > To wind one of these for a 16+16 version FCP for 80 meters, and you are
> > doing the "simple" version with 67 feet or so radiator above the FCP,
> > evenly space *fifteen* bifilar turns around the toroid.
> >
> > 73, and I'm looking forward to a lot more 160 QSO's in the contests,
> >
> > Guy K2AV
> >
> >
> > On Sat, Dec 10, 2011 at 1:38 PM, Bob Garrett <rgarrett5 at comcast.net>
> wrote:
> >
> > > Hello Guy,
> > >
> > > When the dust settles, will you post a list of parts and sources so we
> can
> > > duplicate this antenna and the unique matching network? 73, Bob K3UL
> > >
> > _______________________________________________
> > UR RST IS ... ... ..9 QSB QSB - hw? BK
>
------------------------------
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