Noted some number of times.
My approach is to ONLY ground the two extreme 20 meter elements on the
C31XR (top antenna) since they are the longest and provide the longest
extension for top loading anyway. This appears to minimize voltage
across the other tempting gap points considerably. This being since
they are no longer at the END of the conductor, but some twenty,
thirty feet from the highest voltage.
----- Original Message -----
From: "Tom Rauch" <w8ji@akorn.net>
To: <towertalk@contesting.com>; "George T. Daughters"
<gdaught6@leland.stanford.edu>
Sent: Thursday, February 07, 2002 7:14 AM
Subject: Re: [TowerTalk] Shunt Feed Capacitor for Tower
> Remember that the F12 antennas have elements which are insulated
from
> the boom. I wouldn't be surprised if that made for a less-effective
> top-loading effect.
......and worse yet they can arc across the insulators. The
elements need to be electrically grounded to the boom at the shunt-
feed frequency in many cases to avoid arcing.
73, Tom W8JI
W8JI@contesting.com
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