Looking at "off the shelf" multiband HF vertical antennas (i.e. R8, 6BTV,
etc.)..
Are there any significant(! (>1dB)) radiation efficiency differences
between them that wouldn't be swamped by such installation dependent effects
like grounding, nearby stuff, etc.
They all look like trapped multiband vertical monopoles, as far as I can
tell, and they're all about 25-30 feet long.
Presumably there are mechanical differences in hardware, etc., but what I'm
really looking for is any noticeable "power sucking loads" that are inherent
in the design (sure, our vertical has a 2:1 SWR bandwidth of 200kHz on 80..
we have a 10 dB pad in the 80m trap!)
Jim, W6RMK
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See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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