With the higher attachment point, more series capacitance and zero
capacitance to ground I now have 2.5 to 1 SWR. It also was able to make
several contacts: C6, P40 and W8. I guess it is just a matter of fiddling
with the feed now. Thanks all who responded for the help. See you in CQ160
SSB.
Chuck W5PR
----- Original Message -----
From: "Chuck" <w5pr@swbell.net>
To: <towertalk@contesting.com>
Sent: Monday, February 15, 2010 10:35 AM
Subject: [TowerTalk] Shunt Fed Tower - 160 Meter Gamma Match Question
>I am trying to shunt feed a tower for 160 meters. I have a 135' Rohn 55
>tower with several good sized antennas on it. Guys are insulated. I have
>run an old piece of coax up 35' about 2' off the tower for a gamma. I have
>about a 150 pf variable in series and 200 pf to ground. Ground is 2 -140
>foot radials, elevated 10' (In the past I think I have used larger
>capacitors for this.)
>
> I do not get any match on the series variable with 200 pf, 100 pf and 0 pf
> to ground.
>
> What is the easiest thing to do now?
>
> 1. Shorten the radials?
> 2. Increase the series capacitance?
> 3. Increase the capacitance to ground?
>
> Is my gamma too short?
>
> Thanks!
>
> Chuck W5PR
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