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RIG ISOLATION

Subject: RIG ISOLATION
From: bill.lumnitzer@paonline.com (bill.lumnitzer@paonline.com)
Date: Mon Jul 11 13:12:30 1994
Sorry for not getting back to this sooner but my feed was disconnected for
a few days then a family vacation took precedence!

Received 6 or 8 suggestions regarding ways to improve rig isolation
in a multi-setup including the following:

    1. Bandpass filters between rig and amp.

    2. Coaxial stubs at the amplifier outputs.

    3. Antenna/Rig selection.

    4. Separate towers for each band.

1. BANDPASS FILTERS: These come in XMIT or RCV-only types. Xmit filters are
available from ICE (and elsewhere) or can be home-brewed -see K4VX'articles in
NCJ and Sept '88 QST, and the article in May? '94 QST; these designs include
both 3 and 5 pole versions. Rcv-only filters can be built per the NCJ article
by W3LPL and are a 5-pole design I think; these must be installed in the 
"receive antenna" line of your xcvr since they won't handle any power. Some
stations use both types but it seems like the 5 pole Xmit filters would give
equal performance to the 'LPL ones (ICE filters are 3 pole and have 10-15 dB
LESS rejection than 5 pole types); filters can be cascaded but results unknown.

2. COAXIAL STUBS: Coax stub filters on "tees" (type N recommended) directly at
the amplifier output on each band; sometimes these work better 1/8 wave down
the line or a few feet after the power meter. Since my antennas are remotely
switched at the tower I'm thinking of trying stubs on each line BEFORE the
relay so they can be left PERMANENTLY mounted (isn't rf leakage from good coax
at HF pretty low?). You can use either 1/4 OPEN or 1/2 SHORTED stubs (I recall
seeing an old NCJ article on this by K2TR). Separate sets of stubs tuned for
CW and SSB should be used for best results, giving 25 dB attenuation or so.
Some stations use DOUBLE stubs at the second harmonic to increase the
attenuation while others recommend one stub at both HALF and TWICE frequency
(e.g. stubs for 40/15 and 10 on the 20m station). I tried coax stubs before I
got the ICE filters and they DID help but haven't tried them yet in combination
with the filters.

Another interesting suggestion was to measure the receive power on one band
while transmitting on another. Supposedly TENS or even HUNDREDS of watts
have been found in some situations! N4KG installs protective diode-resistor
networks at the receiver inputs to guard against burnout. I plan to use my
Bird to benchmark my station and then to track improvement? after each step. 

3.  ANTENNA/RIG SELECTION: Different combinations of antennas and rigs can have
a big effect on interference. Using multiple tribanders versus monobanders 
opens the door to more severe interference and should be avoided if possible. 
I use both tribanders and monobanders but plan to confine them to two separate
towers. I'm also thinking of trying some remotely located receiving antennas
(e.g. trap vert. and inv. vee or small tribander).

Some rigs "talk" to each other more than others (e.g. two TS-940s are
purportedly worse than two TS-930s) and combinations of "synthesized" vs.
"non-synthesized" (TS-830) can be tried (or try a Drake R4C for receive).

4.  IF ALL ELSE FAILS: Several reported of having operated up to six stations
pretty much interference-free (except for 2nd harmonic) using the above
techniques with a single tower or rooftop. But this degree of success has not
been universal. In these situations Separate Towers (widely spaced) for each
band were the way to go. I have the space but not the energy to put up and
maintain all this hardware (two towers are enough!). Nothing dramatically new
came out of this except to prove that it CAN be done and there's still room
for a lot of experimentation. Now where is that 50W slug for the Bird....
 
73' de Bill N6CQ/3      Lewisberry, PA
(n6cq@paonline.com)

 

>From Bruce Sawyer" <zf8bs@twg.com  Tue Jul 12 00:58:03 1994
From: Bruce Sawyer" <zf8bs@twg.com (Bruce Sawyer)
Subject: 160m SSB for California QSO Party
Message-ID: <199407111701.RAA19276@eco.twg.com>

In preparation for the 1994 California QSO Party, the Northern California
Contest Club has sent a copy of the contest rules to the ARRL so they could
be published in QST.  I believe this notice is coming out in the August
issue, though it sure is getting close to press time now.  Anyway, we just
received the following note from Warren, NF1J, the editor of the Contest Corral:

   I'm working over the QSO Party Rules here for September QST, and I
noticed
   that you had the 160 meter phone frequency listed as 1815.

   As this is in the generally accepted CW portion of the band, I'm listing
it
   as 1850. If you have a problem with this, let me know and I'll delete it.

Warren's statement implies the existence of a 160m band plan with which I'm not
familiar.  I did check the rules for CQP in previous years and found that we
have always advertised 1815 as the SSB frequency on 160m.  However, I have
little doubt in my mind that Warren is right about this.  Can somebody
please enlighten us about the 160m band plan?  It looks like NCCC is about
to advertise 1815 in CQ and 1850 in QST, thereby making just about everybody
mad at us!

                                             Bruce Sawyer
                                             President, NCCC  

>From Trey Garlough <GARLOUGH@TGV.COM>  Mon Jul 11 18:40:52 1994
From: Trey Garlough <GARLOUGH@TGV.COM> (Trey Garlough)
Subject: Unsubscribe
Message-ID: <773948452.927999.GARLOUGH@TGV.COM>

# in case of false syntax, pse write back how to unsubscribe ... #

Send a message to cq-contest-request@tgv.com that says UNSUBSCRIBE.

--Trey, WN4KKN/6

>From ken.silverman@atlas.ccmail.AirTouch.COM (ken silverman)  Mon Jul 11 
>20:17:41 1994
From: ken.silverman@atlas.ccmail.AirTouch.COM (ken silverman) (ken silverman)
Subject: WX0X M/S IARU HF Championship
Message-ID: <9406117739.AA773950661@atlas.ccmail.airtouch.com>

Dave, Just thought you would be interested in these notes on the 736.  
The more I use it, the more I like it for the its main purpose in life - 
a portable contest radio:




Mike, Congrats on your new IC 736!

Yeah, the notepad is real slick.  Great for mult hunting.  Yes, the 
tuner will basically only tune out stuff under 3 to 1.  Like you said, 
no surprise.  (Though I was surprised by the tuning capability of the 
IC4KL at Luigi's place.  It had a gerat range)  I just read last night 
before going to bed on how to deactivate the tuner when you are using a 
manual external tuner.  I was having the problem of the automatic tuner 
kicking in when I was adjusting the MFJ.  

When you insert the filters, make sure you set the internal software to 
accomodate the filters, or else they wont be active.  There is a 
section on this in the manual on the installation of the filters.  

This weekend I was playing around on 6m - some nice Sporadic-E.  And 
decided to see how far the tuning range was... It went down to 45 MHz, 
then jumped to 30 MHz.  The neat thing is that  cordless phones are at 
the high end of 46 MHz.  I was listening in on all of the phone calls!  
With my high pearch with line of sight to over 100,000 people, there 
are lots of calls to listen to.  ANy idea of how legal this is??  It 
was Sunday, so lots of calls to grandma.  

Other 736 quirks (but minor in the scheme of things):
Internal keyer pot is not all that linear.  The speed changes rapidly 
in the range you normally use for contesting.  I'de also rather have 
the keyer where the mic gain is and vice-versa.  The light is a bit 
bright when you are operating in low light conditions, thus limiting 
your ability to read the buttons (Scott first mentioned this to me, but 
discovered it myself).  The brightness can be changed by an interal 
screw adjustment after you take off the cover.  The CW side tone volume 
is also an internal set screw.  The RIT is a bit rapid in tuning...  it 
would be nice if it WASNT linear, so the first little section went 
slow.  I find I overshoot a station easily when trying to tune him in 
(on CW).  

I know very well what "baksheesh" is.  Also known as spiff, dash, etc.  
When in Africa, anything of importance was done by dashing a guy.  
Usualy dash was a bottle of Johnny Walker Black.  About $6 for a liter 
at the Embassy compound, but around $150 on the black market, which 
equaled 6 months salary.  It got things done.

I am on the air, and my antenna should be OK to ur area.  I have a big 
problem going due east to work Scott, but should be Ok to N/E.

Gotta get to work.  Ken WM2C

>From mraz@maverick.aud.alcatel.com (Kris I. Mraz)  Tue Jul 12 03:29:22 1994
From: mraz@maverick.aud.alcatel.com (Kris I. Mraz) (Kris I. Mraz)
Subject: Non-Contaminating Coax
Message-ID: <9407120229.AA28113@maverick.aud.alcatel.com>

Quoth The Wireman:

"Class IIA is also PVC but is referred to as "non-contaminating". The term
applies to the chemical makeup of the plastic making it less reactive to
the other plastics in the cable for a net result of greater longevity for
all reasons including ultra violet resistance. Under similar environments 
to that of class I, class IIA should last 10 - 15 years. "Non-contaminating"
does not mean direct-buriable, no matter what you may have read in the
periodicals or even handbooks. To an amateur it simply means that no matter
what you do with it, side by side with class I it will last longer, period.
Examples include RG58C/U, honest RG213/U, the CQ 4XL cables."

Wirebook II, Press Jones, N8UG

>From Paul D. Walker <pwalker@mbi.moody.edu>  Tue Jul 12 13:43:30 1994
From: Paul D. Walker <pwalker@mbi.moody.edu> (Paul D. Walker 
<pwalker@mbi.moody.edu>)
Subject: IARU Results - first contest ever!

WOW!  What fun!

I was over at my Elmer's (N9DHN) shack after a VE testing session on 
Saturday AM and I found him vigorously pouncing on CQ's all over the bands.
When he finally came up for air I asked him what he was up to.  He 
responded that he was trying to defend his Indiana section high score in the 
Mixed-Mode category of the IARU HF World Championships (It was probably the 
lowest score published in that edition of QST) ;^)   

After a few minutes of watching and listening my elmer gets up and says he
is going to help his mom close on a house and said I could try "contesting"
for a while [read: until he gets back].  Naturally I said sure.  I was
tentative at first, but once you get that first QSO, look out.  I racked up
20 QSO's in an hour and a half before he came back and bounced me.  Later
that evening, my elmer called me up and said he was retireing until early
morning and the shack was mine if I wanted to do some more contesting.
Of course I did!  Anyway, the results follow:

N9WHG
Indiana
Mixed Mode - Single Op - Total Operating time: 6:31
100 watts
Zone 8

Band            QSOs            Points          Multipliers

15              5               7               2
20              27              73              13
40              7               13              4
80              22              42              7
                -----           -----           -----
Total           61              135             26

SCORE:  135 x 26 = 3510

I know this is a mere pittance compared to the rest of you guys, but I had
a blast playing:  I love getting into a pile up with the BIG GUNS and
getting heard in some foreign country.

My biggest thrill came at 630 utc when 20m was flatter than a pond on a
calm summer day.  I could hear a Hawaii station working the west coast.
Almost no signal, but perfectly readable.   So I figure if I can hear him,
maybe ....   Well I spent about ten minutes calling and finally: "Nancy 9,
again ..."   He heard me!  Thanks KH6FKG for pulling me out.

Also, thanks for being patient those of you who worked me early on
(CI6AO, for one.  I know you're out there.  Sorry about the Henry:(  Nice
score anyway!)

In retrospect, there are alot of things I would have done differently now
given the limited operating time I had.  But, hey, you live and learn.  Now
the waiting begins for next year.  :^)

de N9WHG
--
Paul D. Walker II                       e-mail: pwalker@mbi.moody.edu
Database/System Administrator           phone:  (312)329-4392
Moody Bible Institute                   fax:    (312)329-4496
820 North LaSalle Drive
Chicago, IL  60610

>From len@ariel.coe.neu.edu (Leonard Kay)  Tue Jul 12 13:54:02 1994
From: len@ariel.coe.neu.edu (Leonard Kay) (Leonard Kay)
Subject: 4U1ITU(KB2R op) IARU results
Message-ID: <9407121254.AA03067@ariel.coe.neu.edu>



                       IARU HF Championship 1994

    Call: 4U1ITU (KB2R, op)     Country:  ITU HQ Geneva
    Mode: Mixed                 Category: Headquarters Station

     BAND      QSO   QSO-PTS   PTS/Q    ZONES  HQ STNS

      160        8       12     1.50      3      3
       80       78      152     1.95      7      7
       40      188      482     2.56     10     13
       20      707     2477     3.50     32     14
       15      280      770     2.75     23      9
       10       29       51     1.76      5      2
     ---------------------------------------------------

     Totals   1290     3944     3.06     80     48   =   504,832 points


Equipment Description:  IC-765, IC-2KW linear, 2nd radio IC-745
                        CTv8, 486/33 laptop, PacketCluster
                        
Antennas:       160/80/40:  Butternut vertical 
                       20:  4-el mono + tribander
 (all at               15:  4-el mono + tribander
   ~ 70 ft)            10:  4-el mono + tribander


Words cannot describe the fun I had running this contest from 4U1ITU (and
the casual operating beforehand). It was my first time being DX, and a big
multiplier during the contest as well. What a feeling to drop one CQ on
a band and hear a pileup! And, more than once, while hunting multipliers,
if I had to make more than one call to break the pileup, I found myself with 
my *own* pileup. 

This trip was also a great study in propagation differences. What a trip being 
able to run JA's all afternoon, I also worked more RA9's than I could count, 
and the opening into SE Asia is much easier than in the States. However, the 
transequatorial propagation to Africa which I expected, much like the NA/SA 
over here, didn't materialize, but that may just have been a consequence of 
double-digit solar flux. I also have developed a very healthy respect for all 
those European DXers who are up at 0100-0300Z to give us low-band contacts! 

The lack of a (working) 40m beam reallly hurt me. Without it, I missed a lot 
of 5 point QSO's to the states Saturday night. Nonetheless, I more than 
attained my contest goals.

Many thanks to KA1NCN, WA2CJT, F5NYQ, OE6FOG, and F8RU. I hope to make this a 
repeat performance someday soon. QSL via WA2CJT. I will be printing a special 
YCCC QSL card for this operation.

73, Len KB2R
Yankee Clipper Contest Club

>From Kenneth N Bolin <KBOLIN@dpc2.hdos.hac.com>  Tue Jul 12 10:44:36 1994
From: Kenneth N Bolin <KBOLIN@dpc2.hdos.hac.com> (Kenneth N Bolin)
Subject: Help with modified TH7DXX setting.
Message-ID: <MAILQUEUE-101.940712094436.480@dpc2>

I'd like to set up my TH7DXX so that it is tuned for about half way
between the CW and phone band rather than the center of the band
settings per the manual. Does anyone have these settings or know
where I can get them? I plan on calling Hy-Gain later today but based
on past experience, I'm not sure how much help I will get.

Thanks in advance.

Ken, W1NG (kbolin@dpc2.hdos.hac.com)

>From Jim Reisert AD1C  12-Jul-1994 1102 <reisert@wrksys.enet.dec.com>  Tue Jul 
>12 16:02:48 1994
From: Jim Reisert AD1C  12-Jul-1994 1102 <reisert@wrksys.enet.dec.com> (Jim 
Reisert AD1C 12-Jul-1994 1102)
Subject: Bob Heil on Ham Radio & More show
Message-ID: <9407121502.AA03901@us4rmc.pko.dec.com>

From: lenwink@indirect.com (Len Winkler)
Newsgroups: rec.radio.amateur.misc
Subject: Bob Heil
Organization: Ham Radio & More
Lines: 10

Bob Heil of Heil Sound will be the guest this Sunday, July 17, on the
Ham Radio & More show. If you want to know about sound, microphones,
headsets, etc, Bob is the guy to ask. Ham Radio & More is on every Sunday
at 6:00pm EST on the Talk America Network in many cities throughout
the country and via satellite on Spacenet 3, Transponder 9, 6.8 audio.
For more info, call 602-241-1510.
73,

Len, KB7LPW

>From James Brooks <9v1yc%equator@csar.csah.com>  Tue Jul 12 05:55:15 1994
From: James Brooks <9v1yc%equator@csar.csah.com> (James Brooks)
Subject: IARU Score - 9V1ARU
Message-ID: <2e221426.equator@equator.uucp>

                      IARU HF Championship -- 1994


      Call: 9V1ARU                   Country:  Singapore
                                     Category: Multi Two (Low Power)

     BAND      QSO   QSO-PTS   PTS/Q    ZONES  HQ STNS


      160        0        0     0.00      0      0
       80        1        1     1.00      1      0
       40      161      539     3.35     18      3
       20      400     1602     4.01     30     10
       15      251      945     3.76     19      9
       10        7       19     2.71      3      0
     ---------------------------------------------------

     Totals    820     3106     3.79     71     22

                 Score: 288,858 points



Equipment:  IC735, IC725, Cushcraft A3, HF2V

Operators:  9V1YC, JE1JKL


Well, as you can see by our crappy score, low power really BITES
from here in this contest - even if we are a multiplier to ourselves.
The locals who showed up wouldn't dare touch the radio (scared!) so it 
unfortunately ended up being a 100W multi-two consisting of myself and 
Saty, JE1JKL.

OK, what kind of power was W5WMU running anyhow?  He was so loud on 
20m it was shocking, and so far above any other Stateside signal 
it was weird.  Never heard anything like it. Ever.

Did anyone have a problem with CT9 when scrolling upwards back through 
the log to make a correction?  Crashed everytime.

Anyhow....it was fun, and we were very happy give out a multiplier which
otherwise wouldn't have been there.  Many thanks to all of you who
dug us out of the low power mud, especially on 40m, and all the 
complaints aside, we'd do it again.  Thanks all!

73,

James 9V1YC

-- 
+-------------+-------------------------+
| James 9V1YC | 9v1yc%equator@csah.com  |
+-------------+-------------------------+

>From Dave Pascoe <pascoe@MathWorks.Com>  Tue Jul 12 17:32:12 1994
From: Dave Pascoe <pascoe@MathWorks.Com> (Dave Pascoe)
Subject: IARU Score - 9V1ARU
Message-ID: <Pine.3.89.9407121237.T9492-0100000@zippy>

On Tue, 12 Jul 1994, James Brooks wrote:

> OK, what kind of power was W5WMU running anyhow?  He was so loud on 
> 20m it was shocking, and so far above any other Stateside signal 
> it was weird.  Never heard anything like it. Ever.

Hmmmm.....2 reports now about how loud W5WMU was.  One in the States from 
KM9P and one from the other side of the globe.  Hmmm....very 
interesting.  I guess propagation is truly the great equalizer.   ;-)

-Dave KM3T
 km3t@mathworks.com


>From mike hansow <mhansow@connected.com>  Tue Jul 12 17:45:07 1994
From: mike hansow <mhansow@connected.com> (mike hansow)
Subject: CT Reflector... (fwd)
Message-ID: <Pine.3.89.9407120907.A11847-0100000@hebron.connected.com>




Some time ago I remember seeing something on here about a reflector 
address for K1EA contest software. Does anybody have that info???

Thanks de Mike, KA7CSE   <mhansow@hebron.connected.com>



>From Jim Reisert AD1C  12-Jul-1994 1241 <reisert@wrksys.enet.dec.com>  Tue Jul 
>12 18:11:45 1994
From: Jim Reisert AD1C  12-Jul-1994 1241 <reisert@wrksys.enet.dec.com> (Jim 
Reisert AD1C 12-Jul-1994 1241)
Subject: Need IARU log data on UA9/UA0
Message-ID: <9407121711.AA16834@us4rmc.pko.dec.com>

I'm trying to see how well CT9 did in determining ITU zones for Asiatic CIS
(UA9/UA0, etc.)

If you used CT9 in the contest, can you please send me your <log>.BAD and/or
<log>.ZON file - it will tell me everything I need to know.

Even if you didn't use CT9, and you have a computerized log in some sort of
TEXT format that you can EMAIL me, I would appreciate that as well.  I can
then run that log through CT9 and see if any bad zones pop out.

Thanks & 73 - Jim AD1C
reisert@mlo.dec.com

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