You didn't mention what the symptoms of the rf feedback were, but assuming
it is rf feedback you're experiencing here's what I've found with mine.
The GAP Titan is constructed in such a way that a considerable amount of RF
can be placed on the coax shield. This is because the coax leaves through
the bottom element of the dipole and is thus coupled to the antenna.
I use a 1:1 Balun from DX Engineering (Model DXE-BAL050-H05-A) mounted
about 8 feet from the base of my Titan. This eliminates
RF on the shield (a great cause of RF on in the shack) and reduces noise
pickup (from the shield). There is an application note on the DX engineering
site
www.dxengineering.com for use with the GAP antenna and other similar
antennas.
In addition, it makes it possible for me to ground the shield of the coax
(for lightning protection purposes) by attaching the ground lug on the balun
to a set of ground rods. Without the balun, GAP recommends that you do not
ground the shield anywhere near the antenna (because it detunes the antenna)
In the past, I had RF interfering with my computer on the lower bands. I had
everything very well grounded too, and put all sorts of chokes everywhere in
the shack. Once I installed the balun, the problems were gone.
I hope this helps
Ed
----- Original Message -----
From: "Patrick Hoppe" <phoppe@wi.rr.com>
To: <amps@contesting.com>
Sent: Sunday, July 25, 2004 12:38 PM
Subject: [Amps] RF Feedback Problem
> Hello all,
>
>
>
> I have a problem with RF feedback on 20, 40, and 80 meters. If I run my
> AL-811H, I get RF feedback on those bands. Nothing on 10 & 15. Everything
> is grounded very well, but it is still there. Any ideas?
>
>
>
> Particulars:
>
> Kenwood TS 570D
>
> Gap Titan DX Vertical
>
> Ameritron AL-811H
>
> Heil Pro-set Plus head phones & boom mic
>
>
>
> Thanks,
>
>
>
> Pat
>
> WW9R
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
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