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Re: [TowerTalk] Gamma match for 30M

To: va3pl@cuic.ca, towertalk@contesting.com
Subject: Re: [TowerTalk] Gamma match for 30M
From: SavageBR@aol.com
Date: Tue, 2 Sep 2003 11:07:26 EDT
List-post: <mailto:towertalk@contesting.com>
Hi Andy,
I am using a 204BA (4 el on a 26 ft boom). The directors and reflectors are 
grounded to the boom. So, the total 30 M dipole includes the boom length and 
the effect of the reflector and outer director. My Gamma match is a piece of # 
14 wire that runs from the end of the boom to the mast  on the side opposite 
the 20 M driven el.

There is an insulator in the wire at the mast. The wire slopes from about 16 
inches up the mast down to the outer end of the boom. I was able to tune this 
configuration to either 40 M or 30 M using a variable capacitor in series with 
the feedline at the insulator. The series capacitor is adjusted to about 100 
pf on 30 M. Note you may want to move the tie point to the mast up or down a 
bit to optimize the match. I was able to tune it down to about 1.1:1 at the 
band center.

I have the 204BA at 74 ft and I think the matched boom works out GREAT on 30 
or 40 M. I have used it on both bands.

Good luck,
Bruce  AA4Z  
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