Light,Lazers and HF
This has lead us to the obsurd present point where a cubic foot size
antenna for top band should have
its reflecter a couple of blocks away and of a size stretching for
several thousand feet instead of a few inches
where if the antenna was a ball of presureized water the close
reflector would prevent the jet of water spreading to the rear.
Given a 3 ft copper dipole on 1.9 MHz the free space gain is -4.6 dbi,
and exhibits a classic dipole radiation pattern. Placing a 6 ft diameter,
radial reflector 3 ft from the antenna has no effect on the radiation
pattern,
other than a slight reduction in gain to -5.2 dbi.
Frank
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