Kim Elmore wrote:
> But, how best should I handle a
> station that's up in the air with no hope of a ground run short enough to
> constitute a good RF ground?
There are three types of ground that your station needs. One is the lightning
protection system, which the Polyphaser link covers. It takes a significant
amount of money and work to do it right.
The second is the AC ground. That is taken care of by following the appropriate
building codes when installing the service, using 3-wire plugs on all of your
equipment, etc.
Finally, the RF ground. Ground-mounted verticals need a good ground system, of
course. You can think of that as part of the antenna. But other than that --
you probably don't need an RF ground. If you are feeding beams and dipoles with
coax using baluns where appropriate, or if you are using balanced lines with
balanced antennas and tuners, you should not have trouble with RF on station
equipment. You can always put your equipment at RF ground for a particular
frequency by attaching a 1/4 wave radial to it. Long-wire antennas can be fed
against a resonant counterpoise, for example.
73,
Vic, K2VCO
Fresno CA
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