I re-installed my C3S on a 10' guyed mast with tripod base on the roof
of my row house after re-roofing. The mast also has fixed 440 and 2 m
beams. A trapped dipole for 30/40/80 is slung over the roof below it.
While minor physical things changed, the only thing overtly different is
replacing a BN-86 voltage balun with a bead balun (Wireman kit), that
is, the feedline wasn't changed. I now have more shield current or at
least more manifestation and also have more telephone RFI (of course my
house and the neighbours are well within 1 wavelength). Tamed the rig
by putting a coax coil unun (6 turns of RG8 about 5" diameter from a
previous balun project) in front of my antenna switch, but still wonder
what's going on - don't know whether the unun is choking off shield
currents or just changing feedline length. Other observations are that
the low end of 10m now has a reasonable SWR and both 10 and 12m seem to
perform a bit better, but condx have been strange. It seems to be the
classic symptoms of shield currents, but ???
Anybody have some thoughts on how to approach determining what's going
on?
tnx George VE3YV / K8HI
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