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Old September 26th 07, 10:14 PM posted to rec.radio.amateur.antenna
Wayne Wayne is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 409
Default "Quarter wave ground mounted radials are a waste of wire."


"Richard Clark" wrote in message
...
On Wed, 26 Sep 2007 16:56:27 GMT, "Wayne"
wrote:

It would be interesting to follow the change in VSWR as you add individual
radials. Some years ago, there was a discussion of adding radials until
the
VSWR stopped increasing. This was based on an expected feedpoint
resistance
of 36 ohms, and an assumption that the ground losses were 15 ohms or less.
So at the worst case, the VSWR was near 1:1. The best case, with a ground
loss approaching 0 ohms, would have a VSWR of 50/36= 1.39:1.


Hi Wayne,

This strategy may also have you stop adding radials too early when
your antenna presented 36 Ohms looking into a ground loss of 33 Ohms
(same SWR of 1.39).

73's
Richard Clark, KB7QHC


Right. I guess the better way to state it is to stop adding radials when
the r component stops dropping. I've always wanted to try that experiment,
but real estate considerations have prevented it.