Topband
[Top] [All Lists]

Re: Topband: Variable Flag Termination?

To: Dan Zimmerman N3OX <n3ox@n3ox.net>
Subject: Re: Topband: Variable Flag Termination?
From: David Sinclair <k3ky@radioprism.com>
Date: Wed, 02 Jan 2008 23:34:06 -0500
List-post: <mailto:topband@contesting.com>
> But, I was just wondering if those of you who are using flags (or
> pennants or deltas or other ground-independent terminated loops) have
> found variable terminations to be useful across the bands?    I know
> some K9AY users find them useful, and I know K9AY doesn't favor
> Vactrols but I do have some light dependent resistors and I also think
> I have a hank of old fiber optic cable somewhere and I'm thinking I
> can hack something together that won't require any extra wires near
> the flag...
> 
>
> 73,
> Dan
>

Have you read the work of WA1ION? He has done quite a lot with
remote variable terminations, and has collected extensive data.
I have seen more from him, which a search should pull up easily,
but here's a good one for starters:

Pennant Antenna with Remote Termination Control
http://members.aol.com/DXerCapeCod/pennant.htm

(Quote:)
"At most sites, the pennant antenna offers a simple single-antenna
method of producing a cardioid pattern. Use of a remotely-
controlled termination resistance allows a degree of slewing the
null bearing and depth to reduce interference from numerous
stations in the approximate opposite direction of DX targets
being chased."
(End Quote)

He controls it in the usual way, with a variable DC bias voltage
superimposed over the signal on the coax- but an optical fiber
link would be good, too.

73, David K3KY


_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband

<Prev in Thread] Current Thread [Next in Thread>