Two Meter FM Antenna Question
On 21 Aug 2006 22:07:40 GMT, Ed
wrote:
Every reference and factory specification for
standard grounplane and vertical dipole antennas I've seen indicates the
standard vertical dipole has a horizontal gain of 3 dBi, and the
groundplane 2.1 dBi.
Hi Ed,
Those are pretty curious references then. Why would they dwell on the
HORIZONTAL gains of VERTICAL antennas? There must be something left
unsaid in what you are trying to express because cross polarization
would drive down sensitivities by 20 to 30 dB.
For another matter, those values you quote bear very little
resemblence to typical 2M FM operation, unless it is from the Space
Shuttle. Height above ground variations in gain easily washes over
any differences you might perceive. I can see a variation of 2dB in
just raising a groundplane from 40" off the turf to 120".
73's
Richard Clark, KB7QHC
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