-----Original Message-----
From: comtek4@juno.com [mailto:comtek4@juno.com]
Sent: Tuesday, December 22, 1998 11:48 AM
To: n2tk@idsi.net
Subject: FW: Help - 80m 4 square
Tony;
Ur post forwarded to us.
For starters; without modeling, it sounds as i fthe verticals are
coupling to the tower at 80'; a bit too low for connection.
We suggest the Tee Top Vertical config: current baluns should be retained
in any elevated array, so Rf on the braid is not a problem.
Try at least the NW & SE over Holidays if possible to see if an
improvement is seen. Use dumped power freq/amount as baseline.
73-Happy Holidays & Good Luck;
Jim, K4SQR
Comtek Systems
The 4-Square company.
--------- Forwarded message ----------
From: "N2TK" <n2tk@idsi.net>
To: <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Mon, 21 Dec 1998 19:33:59 -0500
Subject: [TowerTalk] FW: Help - 80m 4 square
Message-ID: <000001be2d43$d9d31260$5e1be8cd@n2tk>
Presently I have a 4 square based on the article in section 6.3 of
ON4UN's
Low Band Dxing, 2nd edition.
I have 4 posts with a vertical wire from each pulled up to the top of the
80' tower. I am using 1/4 wave 70 ohm feedlines to the Comtek box. I have
one radial on each leg pointing away from the tower. There is a current
balun at each feed point.
The differences being -
- the vertical wires are tied into the tower at 80'. This adds more slope
to
the vertical wires.
- the radials and the feedpoint are 12' off the ground
- the vertical wires and 1/4 wave coax are cut for 3.65MHz
- the one radial on each leg is cut to for minimum dumped power at 3.79.
- I switch in a coil in the radial at each leg to have minimum dumped
power
at 3.520.
Performance - about 10-18 db f/b and very slight gain over a Cushcraft
AV80
36' vertical with 4 elevated 1/4 wave radials.
My questions on trying to improve performance
- Thought performance would improve by making the verticals more
vertical. I
can do that by making them
"T's". The vertical portion would be about 45-48' before I added the T.
- Or I could put up aluminum verticals at each post. Thought was to use
8'
pieces of 2" tapering down to 3/4".
- With the radials, do you think I would get a measureable improvement by
either adding one or two more per leg? What about the articles on 1/8
wave
radials? Would that work with a coil?
- Is performance suffering by cutting the verticals and 1/4 wave matching
lines for 3.65 and then switching in a coil in the radials for phone and
cw?
Tnx for any ideas and input. As to not clutter up towertalk, you can send
direct to me any responses and suggestions and I will summarize on
towertalk
Tony N2TK
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