[Elecraft] Small QRP antenna

[Bill Frantz]

I may be seriously wrong, but shorter than 1/4 wave ground 
mounted radials are probably affected by the same ground tuning 
effects that allow a Beverage on the Ground antenna to be 
considerably shorter than one mounted above the ground. If this 
is really what is going on, then a bit longer than 1/8 wave 
should be about right for radials on/under the ground.

73 Bill AE6JV

On 12/29/16 at 9:05 AM, donwilh at embarqmail.com (Don Wilhelm) wrote:

>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.
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