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From: "james moritz" <j.r.moritz@herts.ac.uk>
To: <rsgb_lf_group@blacksheep.org>
Date: Thu, 5 Oct 2006 16:26:04 +0100
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Subject: LF: RE: Am I almost done?
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Dear J., LF Group,

Yes, provided everything is working in a stable way and stays in tune, I
think you are there.=20

It is difficult to calculate a precise figure for radiation resistance =
of a
real-world antenna without accurately measuring heights and lengths at =
many
different points, and putting the measurements into something like NEC =
to
calculate a figure for Rrad. Even then, there usually seems to be a =
certain
amount of loss of radiation due to the environment around the antenna =
that
can't really be determined without resorting to field strength =
measurements.
But from the dimensions you have given, my rough estimate is that you =
are
close to 1W ERP (relative to a dipole). The EIRP (relative to an =
isotropic
antenna) is higher than ERP by a factor of about 1.6.=20

Cheers, Jim Moritz
73 de M0BMU