>Guess what we all need to do
is put a HUGE mass of polyethylene under our beverages to
get the velocity factor down to 0.66, (anyone know the
velocity factor of distilled water? its 0.85 or 0.90, as I
recall)
> Robin, wa6cdr
You may have hit on an idea for a short, effective Beverage antenna here
Robin.
The antenna depends on the velocity coefficient of the soil to be less than
that of the conductor wire. This "inclines" the wavefront from an initial ~
90 degree vertical angle to an ever decreasing acute angle, which then
induces an increasing electric signal in the wire. We just need to force
the "rate of incline change" to take place quicker, and therefore, to
require a much shorter space.
It would appear that if another wire or wires of very low velocity
coefficient, were run under the top receive wire, then much less length of
antenna wire would be required for the same pattern. Possibly steel wire
with a special coating for VC reduction could be installed as a helical coil
under the top wire to get the long Beverage effect. Side rejection may not
be as effective, but the New Improved Beverage could be waiting for
discovery. I would almost kill for a 100 ft Beverage that had the pattern
of an 850 ft model !
73, Doug / NX4D
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