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Old October 24th 06, 01:41 AM posted to rec.radio.amateur.antenna
Brian Kelly Brian Kelly is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 45
Default Minimizing Common Mode Currents by Simple Grounding?

I'm in the process of stringing two base-fed half wave verticals up in
a big beech tree, they're Dale Parfitt's End Fedz dipoles for 20 & 15M.
These antennas are described on this Web page:

http://www.universal-radio.com/catal...wire/4456.html

It seems to me that I have three options for feedline common mode
current minimization/elimination. Beads, coiled coax chokes which is a
quagmire I don't want to get into and plain old grounding. It's the
"plain old grounding" option I'd like to run past the gurus around here
for reality checks on my thinking.

The matching networks will be 12" - 18" inches above the the surface
and fed with 8X coax. The tops of eight foot ground rods will be
directly (+/-) below the matching network enclosures at the bases of
the verticals. I'd split open the jacket of the coax and solder
pigtails made from 3/8" flat braid to the coax shields just behind the
PL-259 fittings then tape/goop the joints to weatherproof them. The
other ends of the braid will be attached to the ground rods. There will
also be some "nominal" radials attached to the ground rods.

Will this arrangement eliminate the need for the usual types of 1:1
choke baluns by taking any I3 currents on the coax shields straight to
ground?

Thanks,

Brian w3rv