[Elecraft] Vetical Antennas

[David Cutter]

Doc

I didn't mean to mislead you: I don't own a 5BTV myself, but there seems to 
be a lot of them around.  If  it is common practice to put them on a pole, 
then the pole ought to be useful on the lower bands using the 5BTV and its 
radials as at least partial loading for 80 and 160.

A simple idea might be to have a separate feeder for the lower bands to the 
bottom of the pole with a loading/matching coil, though it would need a lot 
of wire in/on the ground to make it half decent.  At least the higher bands 
would be relatively efficient.

But I can't help thinking that feeding the pole from the top would be 
workable and perhaps more efficient: I've seen this done with a beam and 
tower arrangement in which the beam is isolated from the tower and an auto 
tuner fitted between.

David
G3UNA


----- Original Message ----- 
From: "James Duffey" <JamesDuffey at comcast.net>
To: "David Cutter" <d.cutter at ntlworld.com>
Cc: "James Duffey" <JamesDuffey at comcast.net>; <elecraft at mailman.qth.net>
Sent: Saturday, March 03, 2007 7:58 PM
Subject: Re: [Elecraft] Vetical Antennas


> Dave - I sure don't have anything specific off the top of my head.
>
> You might try replacing the resonator coil and the whip above that  for 80 
> M with a 40 M trap and extending a wire long enough to make  the antenna 
> resonant on 80 M from the top of the trap horizontally to  a tree or 
> something. You could even droop it a bit/ This would  improve the 
> efficiency on 80 M a lot over the stock arrangement. If  you had enough 
> horizontal space, you might put a 160M trap at the end  of that wire and 
> add enough wire to make that resonant at 160M.
>
> Both of these, while not great efficiency wise, would at least get  you on 
> the band. - Dr. Megacycle KK6MC/
>
> --
> James Duffey KK6MC/5
> Cedar Crest NM 87008
> DM65
>