> Gary Hoffman wrote:
>
> >Also, a wire out the window, to a single ground rod, is likely to to a
poor
> >RF ground. How long is the path total ? I bet it approaches or exceeds
> >1/4 wave at some (many ?) frequencies. Might be an "open circuit" at RF.
> >You might have no ground at all, effectively.
> >
> >
> That is not "a wire," it's 2" copper strap. Through the wall. 8 feet.
>
Ok....8 feet....allow me a little slack and call it say 3 meters. A quarter
wave on 12 meters. Almost a quarter wave at 15 meters. Thus probably not a
very good ground at all on 10, 12 and 15 meters. Probably a good enough
ground at 20 meters and longer. (Assuming 1 rod was enough in the first
place). That was my point. Hint....try a second (or third and fourth if
needed) ground wire in parallel with the 8 footer that is a half wave long
at the shorter wavelengths. This will repeat the low impedance at earth at
the radio. Think of it as a transmission line.
73 de Gary, AA2IZ
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