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Old November 8th 14, 09:14 PM posted to rec.radio.amateur.antenna
[email protected] jimp@specsol.spam.sux.com is offline
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First recorded activity by RadioBanter: Jun 2006
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Default A short 160M antenna - loading and hats

Wimpie wrote:

snip

From 50 Ohms to 2 Ohms is a small step, so matching can be done with
relative low loss. When using an L-match, the loaded Q is 4.9. A
series inductance of about 0.82 uH with a parallel capacitor of 8.2 nF
will do the matching.

Other option is to reduce the value of the top hat series inductance a
bit to create a capacitive series component (of about 8.5 nF). Adding
a parallel inductor will do the matching.


I will just accept that you are correct as I don't want to get into
matching at the moment and off the top of my head it sounds reasonable.

With 4, 15' radials just 2' above ground, at lambda = 518', I would
expect more ground loss, hence higher real part of input impedance.
Are you sure your NEC version handles this situation well?


I do believe so as I can see significant differences between ideal,
good, average, and poor ground.

All this was done with average ground BTW.


--
Jim Pennino