80m mobile antenna question
ORIGINAL MESSAGE:
Dan Richardson wrote:
That may have some validity in the VHF and higher ranges, but on HF -
particularly on 80 meters - a car body's size is a small fraction of a
wavelength (as is the whip portion). Consequently the vehicle body
acts like the one half of a dipole antenna.
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Q. How can a car body which is a "small fraction" of a wavelength act
like one half of a dipole?
A. It can't.
Q. Well, what does it do then?
A. It acts like a short piece of wire leading from the bottom of the
whip to the actual ground plane, namely the earth itself.
Q. Does that help any?
A. Probably a little, but remember the piece of wire (the car body) is
only a few feet long. Not very much on 80 meters.
Q. Thanks, I get it now.
A. You're welcome.
73, Bill W6WRT
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