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Old 31-Mar-2011, 6:31 PM   #2
Dave Loudin
Senior Member
Join Date: Jan 2010
Location: King George, VA
Posts: 659
Originally Posted by retired17 View Post
My theory of why I got better reception is that the radiation pattern across the smaller antenna was more uniform than across the larger antenna. According to the reciprocity theorem, the multipath signals received creates a very complex signal that is not matched to the transmission line thereby causing reflection which is loss. The losses must have been greater than the 3 dB increase in gain. The received signal from the smaller antenna better matched the transmission line resulting in less loss.
You are onto something, but don't think of it as a match to the transmission line. Think about how the signals received by the different elements add up in strength and in phase (the underlying principle of antenna design.) This page at Ken Nist's site has excellent pictorial descriptions of what you're after.

John, I believe I understand what you're thinking. However, that's a lot more metal in the air than necessary. Better to have additional elements cut to the appropriate, i.e. smaller, wavelengths.
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