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Old August 11th 06, 05:03 AM posted to rec.radio.amateur.antenna
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Frank,

If what you are saying is that efficiency is the same for both 36 and
120 radials, then, at least at 8 MHz, B,L&E's findings for LF do not
apply at HF.

Amateurs do not use LF. They use HF.
----
Reg.


You could well be correct Reg. I will get back to B, L & E's paper
and see if I can obtain some correlation between the measurements,
and calculated results At the moment I see 2.5% improvement
between 36 and 99 radials at 8 MHz.

What has also been throwing me off track for a while
was the fact that the input impedance of the 99 radial antenna was less
than than the expected radiation resistance of 36 ohms.
I used this assumption on all my previous
results, so they may have some errors. Applying this technique to the
99 radial antenna would lead to a real resistance component of less than
zero.
Cebik's analysis of buried radial monopoles (www.cebik.com) also
corroborate my findings. Based on the total radiated power, (40% of input)
including surface wave, the radiation resistance is closer to 14 ohms.


Frank



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