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John Passaneau · February 25th 08, 08:51 PM posted to rec.radio.amateur.antenna

"Francesco L." wrote in news:f225cfd7-6bad-45a4-
:

If you can't make a full 1/4 wave vertical, then do your best to make
it as tall as possible, as many, and as long radials as you can, or
make the antenna as high as you can with four radials as long as you
can, maybe loaded by helical or loading coil windings.

My referral to "low band dxing" was just incidental. That was because
info about ground radials are scattered here and there. My target is
to realize a 2 element phased array (which I'm already assembling)
completely homemade and was wondering about the impact that a few or a
lot of radials can have on the system. Obviously I'm talking about a
fixed station, not mobile. Anyway thanks for the contribution, much
appreciated, of you all.
Francesco, ik8vwa

In Low band Dxing and also QST there was information on the number of
radials verses their length. If I remember correctly the basic information
was that distances between the far ends (end that is the farthest from the
feed point) of the radial needed to be some set fraction of a wavelength at
the highest frequency to maximize the performance of a vertical with
radials of any length. So as the radials become shorter fewer of them are
needed to meet this requirement. This not to say that few short radial
works as well as longer radials but for any length of radials there is an
optimal number required and putting down more gains very little. For ¼ wave
radial this number is 120 but far fewer are needed for say 1/8 wave
radials.
I don’t remember the wave length that the article suggested so I will not
make a wild guess.

John, W3JXP