Tom: I have read that grounded elements in a monoband beam are OK, however,
on other frequencies, the connected boom/element system can have unwanted
resonances. That is supposedly why multiband beams frequently use insulated
elements. Assuming that this is true (and I think it is) grounding the
elements of the C4XL could affect its performance. I think it might be
possible to arc across the insulators if you load the tower on 160 but I
suspect a lot of people are doing it. Just my opinion. 73, Dan, N5AR
----- Original Message -----
From: Tom Sykes <nu7j@hotmail.com>
To: tower talk <towertalk@contesting.com>
Sent: Sunday, August 24, 2003 9:31 PM
Subject: [TowerTalk] Re: Force 12 C4XL (with elements insulated from boom) -
bonding anelement to boom to allow shunt feeding tower?
I'm building a Force 12 C4XL (2 elements on 40M, plus C-3 tri-bander). I
plan to shunt feed my Rohn 25G tower on 160M. However, the elements on the
Force 12 antenna are insulated from the boom. I seem to recall reading some
threads on T-T discussing this issue, but I was unable to locate this info
via an archive search. (By the way, my guy wires are insulated from the
tower).
If I remember correctly, the 40M reflector can be bonded to the boom
without affecting the antenna performance. I think someone suggested
bonding through a series inductor (a few turns of wire). Does anyone have
experience or knowledge with this situation? (I tried to ask Force 12 this
question but was unable to make contact them this week.)
Any info would be greatly appreciated! The antenna is going up on Monday
with help from K7LXC.
73,
Tom, NU7J
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
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