On Fri, 07 Aug 2009 16:17:39 -0400, D.W. Fearn wrote:
>Many AM broadcast towers are not resonant -- 5/8 wavelength is
>common. A few capacitors and inductors bring the tower to 50j0 for
>50-ohm coax.
YES. There are many variations on this technique. I'm doing exactly
this with a 160 meter vertical. Works great.
The many folks weeping and knashing their teeth about this have huge
gaps in their understanding of how antennas work. Among other
things, they are confusing the word "resonance: with the concept of
matching to a transmission line, losses in the line due to mismatch,
and antenna performance.
The guy who started it all was absolutely correct. Resonance is
overrated. Understanding fundamental antenna concepts is not. Rather
than post objections to his statement, the time would be better
spent studying relavant chapters in the ARRL Handbook and ARRL
Antenna Book.
73,
Jim Brown K9YC
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