David,
> Yes, yes I agree. But there is something interesting about seeing a self
resonant antenna at these frequencies. Also I remember a QEX article a
while ago that detailed underground dipoles used by USAF for emergency
communication with aircraft. The efficiencies were all less than 5 % but
that's much better than our -30dB etc. The USAF antennas were suspended in
tubes so the antenna had a few inches of 'air' before meeting the soil.
I remember seeing a Buried Antenna' article some time back! I'll see if I
can find this. BTW, when you resonate your antenna don't neglect the the
reduction in length due to the change in 'velocity factor' because of the
proximity of the ground. This may reduce the length considerably (and save
some work/money).
Bill A
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