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Re: Radio S**t CB stuff
On Sep 13, 1:01am, Igor Kessel wrote:
> >since the area surrounding the antenna is used as well.
> > So, in the middle,the whole car would be used as an antenna,
> > helping to pick up signals.
> Sorry, no. A car is a ground. Antenna is well insulated from it.
> Its the high position, unobscured the by the car's sheet metall,
> which acts as a shield, that's what counts.
Just a minor nit here... there's bits of truth in each of
these comments. Jim was essentially correct. Igor was correct
in saying that the car is a ground, but it isn't just the
high position that "counts". For vertical antennas, the
efficiency is greatly increased by having a surrounding
conductive ground plane as large as possible. This is by
*far* the most important effect of having the antenna in the
middle of the roof, especially when we're talking about
wavelengths as large as CB.