I had tried the same thing for a test but used DPDT vacuum relays at both
feedpoints to isolate the feedlines. This way I cold easily switch
polarization from the shack.
Also did a test where I dropped a wire about 2' from the tower. Connected it
at the 40' point and ground. Put a variable cap in series with this wire. I
could change the resonance of the delta loop by varying the cap off the
tower. The delta loop was only 4' off the tower at the apex at 80' and about
15' away at the base wire of the delta loop. Guess I had interaction. But it
made for an interesting way to cover the entire band with a set of relays
and fixed caps on the tower.
73,
N2TK, Tony
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Stuart Browne
Sent: Friday, February 05, 2010 9:18 AM
To: Tower and HF antenna construction topics.
Subject: Re: [TowerTalk] 80m Delta loop on 70' tower
I thought that I'd try it first one feed line at a time, then experiment
with the two feed lines and check performance.
On Fri, Feb 5, 2010 at 8:14 AM, bob finger <finger@goeaston.net> wrote:
> How will you disconnect the feedline(s) from the antenna? A far end
> open ended feedline will become part of the radiator if it remains
> connected to the radiator. 73 bob de w9ge
>
> Stuart Browne wrote:
>
> >On switching from the horizontal to the vertical polorization, I thought
> >that I'd take the ladder line feed from the apex and the feed from the
> >corner and run them to an old knife switch that I have, then ladder line
> >indoors to a 2:1 Balun...pretty basic, but it should work.
> >
> >
> >
>
> _______________________________________________
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