Bill Turner wrote:
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.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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
Actually it is acting as one half of a dipole. It is just a non-resonant
half of a dipole. Remember "di" means two.

Dave WD9BDZ