[Antennas] Re: rf choke

Mon Mar 12 10:41:11 EST 2007

Concerning,
"I am starting my 'monster' horizontal loop, about 3 wavelengths at 160M
averaging about
70' high.
I am very concerned about the certainty of high induced voltages on the
antenna during
thunderstorms. I have heard that I could add an rf choke across the
open
wire line
junction up at the antenna end.
I have never done this, and wonder what kind of choke would be
appropriate
for
160M thru 6M???"
73's
Glen K4KV
Glen,
No. Your concern of dc voltages ACROSS the feedpoint is unfounded. The
loop already is a dc shorting path. A lightning and static path to
ground before the feeders enter your shack is the concern. You can use a
plate style solenoid choke from each side of the feeder to ground
anywhere along the feeder's length. A spark gap in parallel with each rf
choke to ground will protect from more serious strikes. Even two spark
plugs will protect a lot.
73, Roy K6XK