I have been thinking about constructing a BIP-BOP switch using DPDT
relays. I notice that in the diagrams published in the mags using
commercial switch boxes, an extra half-wavelength of coax is switched
into one of the antenna feeds to provide the out-of-phase signal. I
do NOT see any where the second antenna's phase is switched by merely
reversing the center conductor and the shield of one of the antennas
using another DPTD relay. This appears to be easier and cheaper than
yet antother piece of coax with all the extra connectors. What am
I missing???
I would seem the same idea would be usable for a pair of phased verticals,
that is, reversing the center and shield on one of the antennas. Again,
I don't see this mentioned anywhere in print.
Please enlighten me, especially if you have tried it!
Thanks.
Terry Zivney, N4TZ/9
00tlzivney@bsuvc.bsu.edu
>From Larry Schimelpfenig <lschim@mailstorm.dot.gov> Tue Jul 18 18:23:58 1995
From: Larry Schimelpfenig <lschim@mailstorm.dot.gov> (Larry Schimelpfenig)
Subject: Which Vertical
Message-ID: <Pine.3.07.9507181356.A7210-c100000@mailstorm.dot.gov>
Hi Rick. I'm not sure how much real-estate you have in the city, but
before I put the tower/KT34XA up I had two 40 mtr extended zepps. One
ran broadside to Eur and the other was end on. They were up about 50-55
feet in the trees. Working as a dipole on 80 and the design antenna on 40,
they were quite effective broadside. Had some pretty good runs on 40 and
worked most of what I heard on 80. On 20 through 10 they were effective
with ends towards the target. I don't remember the score, but in the WW CW
I know I made top 10 low power.
I assume you're looking for a site from which you can play contest during
weekends. I wish you the best of luck in finding a good qth. I assume the
commute from your old qth to the U was the determining factor in your move.
I have a 55mile commute each way, but have a car pool with 3 other members
and we all get along well, so it's not too bad.
I'd like to think that you can remain fairly competitive until you
identify that garden spot for sprouting aluminum and copper. The existence
of a serious low power contester in the 4th call area helped push me a
bit!
Another thought, if you're in an area where there are lots of tall trees,
wire beams is another solution. PVRC met at KT3Y's qth Saturday. He has
developed some 4 and 5 element yagi's with folded dipole driven elements
for 20 and 15, and 3 elements on 40. They really kick butt!
Thanks for the kudos on the write-up of the fone sprint in last NCJ. It's
interesting that for a long time I had this perception that you were more
of a phone operator and I've always considered myself to be more of a cw
op. Interesting that it would be on fone that I beat you! Gotta run. Hope
to cu this weekend in the Internet Sprint, and in early Aug for CW NAQP.
Good luck on the new "temporary" antenna farm.
Oh, last note, I found that one of the 40 meter dubl zepps fed with about
55-60 feet of open wires tied together and fed with an L Network on 160
worked very well when fed against a couple of elevated radials.
73 de Larry K7SV in VA - lschim@mailstorm.dot.gov
>From ke7gh@PrimeNet.Com (Brian Short) Tue Jul 18 18:34:33 1995
From: ke7gh@PrimeNet.Com (Brian Short) (Brian Short)
Subject: CT Support Line/BBS
Message-ID: <199507181739.KAA18640@mailhost.primenet.com>
I appologize. That was my intention. Brain was turned off when I
entered the address. Sorry, please excuse the bandwidth.
73 de Brian
>Not to be a whiner or complainer myself, but you should have posted
>this message to the ct-users list. It is not clear to me that the
>ct-users list and the cq-contest list are same list.
>
>73, Jim, 'uses WriteLog and RTTY', WA6SDM
>jholly@cup.hp.com
>
>
>From gclark@cel.cummins.com (Gregory W. Clark) Tue Jul 18 17:44:52 1995
From: gclark@cel.cummins.com (Gregory W. Clark) (Gregory W. Clark)
Subject: 2 Radio Station
Message-ID: <9507181644.AA01505@cel.cummins.com>
Hi Brian
I by no means consider myself or my station as top of the line but I can
share what I have.
I have 2 radios...FT1000 and IC761. FT1000 is primary. I have a control
box that allows the headphones to be split, both ears either 761 or 1000 or
split with 761 in left ear and 1000 in right ear. The box also switches
keyer/computer control and mic.
For antennas, I have 2 towers...tower 1 = 10m yagi, 15m yagi and KT34XA on a
sidemount, tower 2 = 40m yagi, 20m yagi, 80 wire, TA-33 fixed SE, shunt fed
for 160m too. I also have a butternut vertical.
I do have an amp but I mainly do low power ops in contest. If the amp is
used it is dedicated to the 1000.
In domestic contests I can get away with using only the vertical on the 761
and all of the other antennas on the 1000. I don't have Dunestar or ICE
filters like you, but it would come in handy at times. In DX contests, I
will slave the KT34XA and the vertical the 761 and all the rest to the 1000.
I use the 761 to tune for mults....it works well. I just need to get the
TA33 on a rotating sidemount rather than fixed. That way, if I was on 20
looking at EU, I could point the TA33 toward the West to pick up anyone
calling on the back of the antenna.
As for grounds, all towers are grounded well. Coax/hardline comes to a
header in the shack and goes through ICE lightning hardware. All rotator
cables have MOV's bypassing to ground...they conduct to ground on pulses
greater than 35V. All equipment is connected to a buss that goes to
rods under our house.
I use manual antenna switches....MFJ remote switches (they really work and
are not too expensive) and Alpha-Delta manual switches. I just have not
dived into the Top-Ten Devices yet...some day maybe.
Is that what you're looking for??? If not, sorry to was the mail space, but
if it helps, great! If I can answer anything else, please let me know.
73/Greg
KO9Y
gclark@cel.cummins.com
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