Marty, Shunt feed and don't even think about the inverted L. The benefits from
the top hat not interacting with the beam are worth it alone. A 72 foot tower
with a KT-34 are potentially a dream TX antenna for 160. Concentrate on
radials, buried or elevated, and your shunt feed which should be a large
diameter cable. Cable TV Hard-line (.500 or .750) spaced 12 inches to 24 inches
make an excellent shunt feed. Perhaps someone would be willing to model the tap
for you. I guess it should come in at about 40 to 48 feet with about 350 pf to
tune out the reactance. Use a variable to get in the ball park and look at the
mesh so you can approximate the capacitance. Then replace the variable with a
good quality broadcast type fixed mica. A setup like this should put you in the
top ten topbanders in your area. Give it a try and forget the inverted "L".
Good Luck
Herb (KV4FZ)
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