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Old December 13th 03, 06:41 PM
J M Noeding
 
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On Mon, 8 Dec 2003 07:58:57 +0000, "Ian White, G3SEK"
wrote:


You can't directly measure radiation resistance, because it's embedded
in loss resistances and usually reactance too. Also there's more than
one definition of radiation resistance: some would say that the
radiation resistance of a half-wave dipole depends on where and how it
is fed (centre, end, off-centre); while others would say that the
radiation resistance stays the same, and it's only the feedpoint
impedance that depends on the method of feed.

Since you can't measure it and there isn't even a universally agreed
definition, it's best to tiptoe quietly away from "radiation resistance"
before the Holy Wars begin...


I don't wish to participate in this real discussion since I have only
a vague memory of what we had at school over 30 years ago, and math -
and in particular integration - is not my strong side.
Could you suggest any values of what one could expect to find for
radiiation resistance for some variations of half wave dipoles,
dependent on wire size, height and other?

73
Jan-Martin, LA8AK
http://home.online.no/~la8ak/a.htm
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