.
<< k1oa@mediaone.net (Scott Ginsburg),
Open wire line doesn't radiate if the currents are balanced and I've run
it fairly close to power lines of 1-2' when necessary and other wires without
a problem. Coax with RF spill over on the shield got into everything
regardless of distance. If a ground cable to the ground rod is 1/4 WL long
it will present or be a Hi-Z at the connection and do nothing. It's always a
DC Ground.
Adding the toroid donuts to the power lines should help cool them from
stray RF from the antenna. Palomar has a meter to measure RF on power wires
or coaxes.
called the RF Current Meter PCM-1. Since I use techniques that prevent RF
Spill over now I never measure any RF on my coaxes in the shack anymore.
Power lines in conduit is a good idea all the time.
If your matching system permits balance adjustments, there is a simple
test of true balanced feed. For example with a T or Gamma Match (Gamma is
the last resort) match using the MFJ SWR Analyzer, place your had on the
center of the DE, coax shield or mast and see if it upsets the SWR. If it
does adjust ends until no change of SWR occurs (1:1 properly adjusted for
SWR). If your system still has spill over the Toroids at the feedpoint are
RF resistors and will dissipate it (2nd choice). The coiled coax doesn't
work in the high current section. It works 1/4 WL lower at the Hi-Z or E
point. If you use open wire line I suggest RF Ammeters to check balance of
the currents.
k7gco
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