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Old June 28th 05, 04:57 PM
Richard Clark
 
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On 27 Jun 2005 23:55:20 -0700, (Gorm
Helt-Hansen) wrote:

It is ground mounted with 24 buried radials. I have tried with extra
radials cut for 50 MHz. If I make a short over the 18 MHz coil the 48
MHz resonance disappears and the SWR on 50 MHz is perfect. But it
don't work if I detune the coil, short some of the turns or remove the
capacity hat.
I have read on some newsgroups that other have had the same problem,
but I have never seen if they have solved it.


Hi Gorm,

You might try a couple of radials that are above ground level by 20cM
or so and tune them. Your antenna is really designed to be mast
mounted, and it would be better for 6M operation. The reason for this
is that at ground level, 6M is seeing far more clutter from your
house, garage and neighborhood, in its propagation characteristics.

Propagation has nothing to do with the matching problem, but it is a
matter of practical application. With a higher antenna, you can
control the resonances of each band with tuned radials (which are not
tuned so close to, or in ground). With a higher antenna, shorter
wavelengths are impeded less by obstructions.

73's
Richard Clark, KB7QHC