Hello Bill & reflectees
the problems of switching at the high impedance tip of a quarter wave vertical
can easily be overcome.
I would suggest a trap ! Like on other frequencies it would serve to decouple
the lower frequecy part of the antenna from the higher frequency resonator.
It will be a bit bulky, but by far less troublesome as a relay up in the rough
winterly environment.
And there is another physical problem that has not been looked into :
The vacuum relay yields an external spacing of maximum 2 inches.That distance
is
too close to avoid coupling- which is very high at that impedance.
I tested that by using a wire to fix a dipole- using 4 inch insulators- and it
was impossible to get resonance ! i had to use Nylon cord to get it right. That
proves the problems with the high impedance points.
Thats the best advice i can give from my experience with antennas.
73 de wolf df2py
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