I traded in years of low band wire antennas for a shunt tower feed. I have
a 3 section freestanding 54 ft tower on a small city lot. 11 elements from
3 antennas provide the top loading. I use a single 3/8 inch rod from the
gound to the top of the bottom (fixed) section, 15 inches from one tower
leg. An omega match with vacuum variables is switched for the correct match
for 160, 80 and 75. Single rod and tap point for all 3 frequencies. No
radials - none. Tower cables are outside the tower on coax arm extensions
to the roof line.
I have no delusions about setting any records, but it takes power and
works. 40m rotary dipole comes in handy for RX. I do not believe that
finding an optimum match point futher up the tower would offer any
improvement over the omega match. At least for this installation.
It's worth a try. If you run power, the vacuum variables are a must.
Wish I'd tried it years ago.
73, Steve WB6RSE
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