When one is talking of a home station where the situation is relatively stable,
it is now not difficult to measure the antenna feed impedance, and then
design/build a tuner to allow matching. For an open wire feed, the old ARRL
handbooks with the parallel or series tuned circuits do the job of a balun
while for a single wire, an L network in one of its possible forms will do. You
can even have a separate tuner for each band.....Big HV high current switches
ex BC375 Tuning Units are cheap enough at Fair Radio.
Admittedly, 160 can be a problem: my folded unipole when top loaded with a
205BA and a CueDee 4 ele for 10 interlaced with 4 ele for 15 allowed me to just
adjust the tuning cap in the L across all of 160 and 80, which the 4 ele
Steppir doesn't - that needs both L and C adjusted over each band and still has
a high Q on 160 - as the wind blows, the wires feeding the unipole move and SWR
wags around. But still, a home brew unit is MUCH cheaper if you go to flea
markets - although I did spend $75 on a 500pF 7500volt vacuum cap for the tuner
for the vertical.
I find the biggest problem is getting the low rpm DC motors for remote
tuning......have to go to stepper motors.
73
Peter G3RZP
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