On 6/1/2013 9:34 AM, GEO Badger wrote:
Alas, that is not true. Gain is reciprocal on antennas.
http://www.ece.rutgers.edu/~orfanidi/ewa/
Yes, BUT -- on the HF bands, what usually matters on RX is DIRECTIVITY,
not gain. That's because what we hear is limited by noise picked up on
the antenna, not circuit noise in the RX itself. Also, antenna
directivity is three dimensional -- their vertical and horizontal
patterns can be quite complex, and most practical antennas are polarized
-- that is, they transmit and receive more energy horizontally or
vertically polarized. Those properties are also reciprocal, and they
can either enhance receiving or make things worse, depending on the
directions from which signals and noise are arriving, and their
polarizations.
73, Jim K9YC
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