> You really do not need stranded wire. Bare solid wire is typically used
> for grounds.
Solid wire lasts longer, and is easier to connect to later because it is
easier to remove all corrosion without chemical cleaning or strand-by-strand
cleaning.
Also beware of gutting old wires, because some (like twinlead) are copper
clad steel with thin copper. After a while, it will rust apart.
Nothing lasts like solid copper. I use #16 tinned copper buss wire, bought
on 5000 foot reels. Stuff installed in 1998 looks like new when I dig it up,
and lightning never has melted it.
and while the standard of 120 radials spaced 3 degress is a
> well known standard for ground systems, it is very rare in amateur
> radio. >>
The only reason 120 radials were ever used is because the FCC excludes some
complex verification measurements when a standardized system they chose is
used. It has nothing to do with how it works. Often, 30-50 radials is
immeasurably different than 120.
> Having installed many MW systems, I can tell you the ideal is not always
> achieved. At the end of the day, get as much wire in the ground wherever
> it is possible.
That is always the best advice, because even similar systems and locations
can be different. Also, measured base resistance does not translate into
efficiency. I've had 1/4 wave verticals with ground systems making 50-60 ohm
base resistance equal in performance to the same antenna, at the exact same
spot, with radial systems making 35 ohm base impedances. This is because
radials have standing waves, even buried radials, and transform impedance.
73 Tom
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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