Aloha,
I posted the following on the Top Band reflector hours
ago; so far it has not appeared there nor in their archives.
Strange reflector that one; puts out what appears to be
some kind of digest every several hours!
Anyway, here is my questions:
Longest wire I can get up here is my 80/40 meter
W7FG doublet about 125 feet long; center fed via
600 ohm ladder line. So, it is about 1/4 wave on
160 metes.
Using my tuner, with extra capacity
switched in at the output capacitor to yield about
450 pf at the output, I can reach an indicated
vswr of about 1.7:1.
However, it seems to me that feeding a 1/4 wave
antenna at the center is not the right thing to do!
So, given the achieved vswr here at the input of the
tuner, is it "safe" to use, feed the set up some power?
Seems that a LOT of voltage may sit at the tuner.....?
Capacitors in the tuner are rated at 6kv. Tuner inductor
is rated at 5kv, 30 amps.
For use with balanced ladder line, this particular
tuner uses a 1:1 current type, Ferrite core balun
at the tuner input, not as is usual at the output.
A a few years ago I was invited to take down my very
long wires I was using on 160; the wires happened to
cross plantation land leased by someone else!
Should I try this set up? After thinking about this for
a time, it seems that maybe the maximum current area
will be in the balanced ladder line feed, and thus, my
rigs power will be canceled in the far field! But at least,
some signal would be getting out on 160 from Kauai.
73, Jim KH7M
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