question on random wire anttenas
"an old friend" wrote in news:1138059456.579317.228830
@o13g2000cwo.googlegroups.com:
having lost the support on my 6m beam and haing a turner able to tune a
random wire I have decided totry it
since i don't know I will like it id rather avoid cutting this nice
piece of wire
thinking about unwiding some wire from a 1/2 mile spool anythoungts on
howmuch and what happens if I don't cut it off the spool(just unwind
10ft fifty or whatever leaving one large inducer on the end of the
"antenna
The thing with random wires is that you get a voltage loop at the end and
then voltage loops every half wave back towards the feed end. At the
feed end you will have some random combination of reactance and
resistance to feed, which will tend to require a tuner. And you'll want
a counterpoise to ground it all. For that a quarter wave of wire will do
(or a half-wave attached to the tuner's ground post in the center).
Without a good counterpoise, your tuner and rig may get a bit hot RF-
wise.
--
Dave Oldridge+
ICQ 1800667
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