> 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 used a series of RF relay points to disconnect a 20 ft tall (100ft wire)
zig-zag topload from a 60 ft tower, expecting to get resonance on 80m. Due
to the capacitance through the open relay points, the topload coupled enough
to only raise the resonance freq from 1.85mhz to 2.1mhz. The series
connected relay points did not arc on 80m, using the amplifier.
I am thinking of building a motor driven switch using a solenoid style
copper rod through a fiberglass pipe, to get a 3 ft electrical separation,
as it sure would be convenient to use the same tower base feed on both 80 &
160 meters. Until then, the tower with the vertical topload connected,
seems to work good on 80m by feeding the tower base with a hand-switched in
voltage feed network.
Good Luck, Doug / Nx4d
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