[Elecraft] Small QRP antenna

[Mel Farrer]

One thing I will add that has not been commented on, is the way of feeding a 1/2 wl wire with a 1/4 wl twin lead. Where one side of the twin lead at the top is connected to the 1/2 wl wire.  You can feed the twin lead at the bottom with a 1:1 choke and you don't need a ground. Then for the upper bands, tie the twin lead together and feed it against your counterpoise.  The twin lead does not have to be completely vertical either.  

Mel, K6KBE


      From: Don Wilhelm <donwilh at embarqmail.com>
 To: Richard Fjeld <rpfjeld at outlook.com>; "elecraft at mailman.qth.net" <elecraft at mailman.qth.net> 
 Sent: Thursday, December 29, 2016 9:05 AM
 Subject: Re: [Elecraft] Small QRP antenna
   
Dick,

With buried radials, they do not have to be 1/4 wave long, and a single 
one will probably not make much difference over your ground rod.
What you want to accomplish is a "ground screen", which means many short 
(about 1/8 wavelength) close to the base of the radiator and a few 
extending out further (to 1/4 or 1/2 wavelength).

Ground conductivity plays a great part in buried radials, and what you 
are trying to accomplish is to increase the ground conductivity in the 
area at the base of the antenna.

If you were instead using elevated radials, they would have to be 
resonant - think of the various "ground plane" antennas that have been 
published - 1/4 wave radiator plus 2 or 4 1/4 wave radials.
Buried radials do not have to be resonant, elevated radials must be 
resonant.  The ground effects will alter the resonance of buried radials 
while radials in the air are a part of the total antenna resonance.

73,
Don W3FPR

On 12/29/2016 11:49 AM, Richard Fjeld wrote:
> With reference to below, I have a question please.  I put up a quarter
> wave inverted-L for 160 meters.  My only counterpoise is the ground rods
> at the base of the tower.  I wasn't expecting much, but it does so well
> I'd like to add a decent counterpoise.
>
> If I bury a quarter wave wire, would it be best to put it under the
> Ariel wire, or opposite from it?
> Thanks in advance,
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