Hi Eddy,
Yes, above some voltage all insulators let high voltage through. Most "common"
wire insulation is only good for about 600 volts. Take care not to become a
bleeder resistor. Your idea of the RF choke is better than resistors to ground
as there should be lower signal loss.
GUD DX OM.
See you in the pile ups,
73
Bruce
----- Original Message -----
From: Eddy Swynar
To: Bruce
Cc: topband@contesting.com
Sent: Thursday, November 15, 2012 10:31 AM
Subject: Re: Topband: Covered /bare antennn wire
Hi Bruce,
I am not so sure that the notion of insulated vs. uninsulated wire holds true
in long wire spans...
Case in point: years ago when I first erected my 1500' long Beverage antenna
here, I was specific in using insulated wire though its entire course because
it runs through a grove of trees at one point. Well, one day, in the advance of
an approaching storm front, I decided to ground the end of the Beverage in my
shack. I could feel a "tingling" sensation as I man-handled the wire,
negotiating my way to the common ground pipe that I have running the length of
the back of my operating table...imagine my complete & utter shock as I neared
the wire to this same pipe, and managed to induce 1/8" long blue arcs from the
pipe to the wire!
Since that time---FWIW---I have always had a rugged 2.5 mh. RF choke clipped
between the wire's end where it attaches to the matching transformer, and
ground. In theory this acts as a static drain, I guess, but does not induce
signals to ground. I've heard that a multi-megohm resistor will do the same
thing at this point...
~73~ de Eddy VE3CUI - VE3XZ
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