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Old October 29th 07, 12:21 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
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Default Supposed comparison of Mobile HF Antennas in November QST

Jimmie D wrote:
I once saw a demonstration that "BIG UGLY" cb antennas, these are
approximately 1/8 wl and have a huge loading coil, have more gain than a 1/4
wl radiator. This certaily appeared to be the case when both the antenna
being test and the field strength meter's antenna were both the "big ugly"
variety and relatively close together(50'). Could this "gain" be a result of
magnetic coupling between the coils or was some other trickery being
performed.


Most likely trickery but could conceivably be achieved
through phasing of co-linear radiators. The total radiated
power was no doubt less than the 1/4WL but the phasing
might have caused constructive interference in the remaining
RF waves in the direction of the detector. A loaded CB
antenna does not normally require a "huge loading coil"
so it may have been a phase-reversing coil of sorts as
described by Kraus.
--
73, Cecil http://www.w5dxp.com