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 John Dorr K1AR" <p00259@psilink.com Tue Jul 12 22:09:56 1994
From: John Dorr K1AR" <p00259@psilink.com (John Dorr K1AR)
Subject: 1994 CQ Contest Survey
Message-ID: <2983129723.1.p00259@psilink.com>
Thanks to everyone who replied to my message about the CQ Contest
Survey. As promised, attached is a copy of what we will be running in
the September issue. Feel free to be the first kid on your block to
respond and send me your survey reply via Internet.
73 John, K1AR
1994 CQ Magazine Contest Survey
Your Callsign (optional):
Contesting Experience (years):
1) Do you favor the concept of limiting contest operation to
portions of bands, thus creating "contest-free" operating
zones?
YES NO
2) Who would you recommend should be the next inductee into the
CQ Contest Hall of Fame?
3) What do you predict the winning CQWW scores will be in the
year 2000 for the following categories:
Single Operator/USA SSB
Single Operator/World SSB
Single Operator/USA CW
Single Operator/World CW
4) Do you support the elimination of the traditional 59/599
portion of contest exchanges in favor of more meaningful
information?
YES NO
5) Should the single operator category:
A) Be limited to using only one radio? YES NO
B) Be allowed to use packet spotting? YES NO
6) What was your first contest operation?
7) How did you become interested in contest operating (circle all
that apply)?
A) Contest Elmer
B) Discovered contest operating while operating radio
C) Local radio club
D) Magazine
E) Other
g?8) At what age did you start operating contests?
9) Do contests still have the same appeal for you that they did
when you began?
YES NO
10) As a contest operator, what feature(s) would you like to see
in the next generation transceiver?
A)
B)
C)
D)
11) Are you in favor of limiting transmitter output power to 100
watts for domestic contests?
YES NO
12) If you had the power to change one and only one aspect of
contesting, what would you recommend?
13) In a few words, how does your spouse really feel about your
interest in contest operating (Ladies--feel free to answer
this question personally!)?
Additional comments:
(use extra sheets if necessary)
Return your survey responses to:
John Dorr, K1AR
1994 Contest Survey
c/o CQ Communications, 76 N. Broadway, Hicksville, NY 11801
Deadline: November 30, 1994
------- End of Forwarded Message
>From Trey Garlough <GARLOUGH@TGV.COM> Tue Jul 12 21:57:59 1994
From: Trey Garlough <GARLOUGH@TGV.COM> (Trey Garlough)
Subject: CT Reflector... (fwd)
Message-ID: <774046679.156000.GARLOUGH@TGV.COM>
CQ-CONTEST@TGV.COM Frequently Asked Questions (FAQ) List
Revised: June 20, 1994
What is CQ-CONTEST?
CQ-CONTEST@TGV.COM is an electronic mail reflector dedicated to hams
interested in all types of amateur radio contesting. This is a good
place for score reports, expedition rumors, and other contest-related
discussion or announcements. This forum is more like the NCJ than
QST; INFO-HAMS@UCSD.EDU and rec.radio.amateur.misc are good places to
look for a more rounded discussion of the hobby.
Although there is overlap between contesters and DXers, CQ-CONTEST is
not a DX-oriented group. DX@UNBC.EDU is an electronic mail mailing
list dedicated to the discussion of DXing. For details on how to
subscribe to this and other mailing lists, consult the List of Lists
at the end of this message.
Each message you send to CQ-CONTEST@TGV.COM will be sent out to all
the other subscribers, kinda like a 2-meter repeater that has a
coverage radius of 12,000 miles or so. Think of sending mail to the
list as the equivalent of an ANNOUNCE/FULL message on PacketCluster.
Use regular email to send a message to a specific individual.
Electronic mail is also different from packet radio, in that many
subscribers receive their email through commercial services such as
CompuServe and MCImail. In essence, many people are paying for each
byte of every message sent to CQ-CONTEST. In order to minimize
spurious messages, follow the operating hints detailed below.
How do I join CQ-CONTEST?
Subscription management is handled automatically by a program that
answers mail send to CQ-CONTEST-REQUEST@TGV.COM. Send a message to
CQ-CONTEST-REQUEST@TGV.COM that says SUBSCRIBE if you wish to join the
group, or UNSUBSCRIBE if you want to drop out. The Subject: line is
ignored. Messages sent to CQ-CONTEST@TGV.COM are broadcast to *all*
readers, so don't send subscription requests there.
What are the suggested "operating practices" for CQ-CONTEST?
Put your name and call sign on every message you send. We don't all
know everyone by just a call or a nickname.
Use a subject line that indicates the true subject of your message.
Wait a while before answering someone's question. Six other people
have probably answered it already. Most answers should go directly
to the person who posed the question, rather than to the list.
Unlike PacketCluster, many people pay $$$ when they receive messages.
Some people pay per message, some per byte. Therefore, please take
this into consideration when writing a response. Would you pay $0.50
to read the message that you just wrote?
Eschew flamage. If someone sends a flame to the list and you can't
bite your tongue, send your flaming reply directly back to the flaming
individual, not back to the list. No one wants to pay $1.00 to read
these messages (the original flame + your reply). Treat flamers the
way you would 2-meter repeater jammers - ignore them.
Make sure there is something of value in each message you send to the
list. Avoid messages that are a complete reprint of someone else's
message, with nothing but "I agree" or "Me too" added to the bottom --
not much value there.
Some people pay by the byte, so when following up to someone else's
message, be sure to include only the essential pieces or thread of
the note. Don't include those 20 extra header lines that your mail
gateway tacked onto the original message.
How can I find out the email address of a particular contester?
John Pescatore, WB2EKK (pescatore_jt@ncsd.gte.com), and George Fremin,
WB5VZL (geoiii@bga.com), maintain fairly current lists of
contester email addresses. Send a note to them asking for their
lists. You can also get a list of registered CQ-Contest subscribers
by sending a message to CQ-Contest-Request@TGV.COM that says REVIEW.
How can I find out more about the Internet?
Pick up a copy of the book _The Internet Companion_ by Tracy LaQuey,
Addison-Wesley, ISBN 0-201-62224-6. If your local technical book
store doesn't carry it, you can order from Computer Literacy,
2590 North First Street, San Jose, CA 95131. Their phone number is
408-435-0744.
73, The Wouff Hong
List of Lists
-------------
CQ-Contest@TGV.COM
Contest forum
DX@UNBC.EDU
DX forum
QRP@Think.COM
QRP forum
VHF.icon_fonts@xeroxaffiliates.xerox.com
VHF forum
VHF-Request.icon_fonts@xeroxaffiliates.xerox.com
Boatanchors@GNU.AI.MIT.EDU
Old ham gear forum
VHF@W6YX.Stanford.EDU
VHF forum
N6TRLOG@CMicro.COM
N6TR logging program forum
ct-user-request@mlo.dec.com
K1EA's CT logging program forum
ham-tech@netcom.COM
forum for people with technical ham related questions (antennas,
radios, digital communications, etc) to share information with
each other
w1aw-list@World.STD.COM
distribution list for the dissemination of official news and
information from the American Radio Relay League (the "League")
ky1n-list@World.STD.COM
distribution list for the dissemination of volunteer examination
information in New England
ham-ant@UCSD.EDU
Bidirectional mailing list with Usenet group rec.radio.amateur.antenna
ham-bsd@UCSD.EDU
A discussion group for people interested in ham radio applications of
the Jolitz 386BSD software.
ham-digital@UCSD.EDU
Bidirectional gateway with Usenet newsgroup(s)
rec.radio.amateur.digital.*
ham-equip@UCSD.EDU
Bidirectional gateway with Usenet newsgroup rec.radio.amateur.equipment
ham-homebrew@UCSD.EDU
Bidirectional gateway with Usenet newsgroup rec.radio.amateur.homebrew
ham-policy@UCSD.EDU
Bidirectional gateway with Usenet newsgroup rec.radio.amateur.policy
ham-radio@UCSD.EDU
The HAM-RADIO mailing list is an experimental digest using subject
grouping and MIME encapsulation to provide a daily dose of ham radio
related traffic from the Usenet
ham-space@UCSD.EDU
Bidirectional gateway with Usenet newsgroup rec.radio.amateur.space
info-hams@UCSD.EDU
Bidirectional gateway with Usenet newsgroup rec.radio.amateur.misc
>From Jim Stevens, KI4HN" <ki4hn@jabba.Cybernetics.NET Wed Jul 13 00:12:32 1994
From: Jim Stevens, KI4HN" <ki4hn@jabba.Cybernetics.NET (Jim Stevens, KI4HN)
Subject: W5WMU
Message-ID: <Pine.3.89.9407121930.E19259-0100000@jabba>
On Tue, 12 Jul 1994, Dave Pascoe wrote:
> Hmmmm.....2 reports now about how loud W5WMU was.
Make that 3. I was CQing on 80M. Most callers were S7-S9 barely above
the noise level. W5WMU was easily 30db over S9. He was so load that when
I first heard his signal I thought he had to be local. BTW, I'm in NC, and
he's in LA. Wow!!
73, Jim, KI4HN
ki4hn@jabba.cybernetics.net
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