Dennis:
I had considered the same thing with respect to use of the HyTower on 160
meters. I did not find a good source for the Teflon so at this point I am
planning something different.
I have decided to top load the HyTower for 160. I have made provision to
tilt the tower over and then raise it again with top hat wires (a
T )attached to the tip of the stinger. I am planning to put a shorting wire
between the top plate of the tower and the stinger so that there is no
potential difference between the tower itself and the stinger.
All of this implies the following:
1. One feeds the bottom of the tower and the wire connected to the stinger
rather than putting a coil in series with the stinger and feeding both the
coil and the base.
2. This solution will work on 160 and perhaps 80 but will require matching
networks to feed power to the antenna and the networks will be different on
each band.
3. The feed point impedance of the antenna should be higher on 160 and on 80
than the regular HyTower which should provide slightly higher radiation
efficiencies.
4. The HyTower will no longer be a quick band changing antenna until the
regular configuration is restored. (Not a problem as far as I am concerned).
***** Note *****
I have not actually done this yet, I am planning to do it in September when
I am at my Idaho QTH. It may not work. There may be problems. If so I will
advise people who are interested. I am mentioning it because I think it is a
better solution than the one using Teflon insulators.
Tod, KOTO
-----Original Message-----
From: towertalk-admin@contesting.com
[mailto:towertalk-admin@contesting.com]On Behalf Of Dennis Ashworth
Sent: Sunday, September 08, 2002 1:30 PM
To: Towertalk@contesting.com
Subject: [Towertalk] Teflon Tubing Source Needed
I am rebuilding a Hy-Tower and want to replace the reportedly inadequate
top insulator sleeves with Teflon. This has been reported as a good
solution to prevent arcing across the insulators on 160M. The dimensions of
the existing insulators (material unknown) are 2" ID, 0.25" wall thickness
and 4" long. Does anyone know where I can purchase a foot of Teflon tubing
with the above dimensions?
Thanks
Dennis, K7FL
Battle Ground, WA
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