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[TowerTalk] (the) Actual Capacitor for Shunt-Fed Tower

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Subject: [TowerTalk] (the) Actual Capacitor for Shunt-Fed Tower
From: (Mike & Coreen Smith)
Date: Fri, 8 Feb 2002 18:56:05 -0400
I misplaced the original post,and had only just scanned it quickly (so I
can't be 100% sure of the the original question) but was the person asking
what to actually use as a capacitor?

I found a couple large air variables (600-800pF range) for my 80m/160m
inverted L's, *HOWEVER* I understand
that you could do the same thing with a length of coax, like RG8, if you had
a rough guess how much capacitance
to put in series with your gamma.  Consult your coax table for the
"pF/foot", but I think it runs roughly
10-20pF/ft (or whatever), so it would just be a matter of coiling up 30-40'
(or whatever you think you might need) and
and trimming to match  and as they say "Bob's your Uncle". No expensive
vacuum variables to buy, nor scrounging through countless bins at your local
flea markets for the perfect air variable. The center is connected at one
and the braid at the other.  I used this to tweak an 80m vertical (whose air
variable was just outside the range I needed) some years ago so I can't say
with certaintly what length might be neccesary, but I remember it was FREE!


Mike 'AA

Michael, Coreen & Corey Smith
(VE9AA,  VE9AAA & Little-VE9 to be)
271 Smith Rd
Waterville, NB
E2V 3V6

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