Roger Halstead wrote in message . ..
I've played a bit with inverted Ls, but I'm going to try one on a 100
foot tower with a TH5 at 100 feet, 28'8" 6-meter yagi at 115 feet and
the UHF and VHF arrays at 130 feet.

By my calculations the tower should be close to a half wave, or
slightly shorter than a half wave.

I know that some tower heights and antennas can pose a problem such as
the 70 feet and a tribander listed in the handbook.

This antenna will be about 80 to 90 feet vertical and the rest
horizontal.

Has any one out there tried anything close to this?

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)

Dunno...Offhand, I don't think it will look that long myself. The
largest beam is 30 ft lower than the top. I think that will reduce the
effectiveness as a hat. The beams on top are fairly small per 160m,
and probably won't amount to a whole lot. Unless indicated otherwise
by an analyser, I'd assume it to act just a tad longer than a 1/4
wave. You could add top loading wires if you wanted to raise the
current max higher up the tower. Being the tower is likely grounded,
I'd shunt feed it. You could also probably rig up a linear loaded
sloper also.
But a top hat with even symmetrical spokes would give you a cleaner
vertical pattern, with an overhead null. If you run a wire to only
80-90 ft, and then out horizontal, I don't think the height of the
tower will matter. It won't be part of the antenna, except maybe for
close coupling. Or do you mean running the wire out from the grounded
tower itself? MK