Hello all,
Thanks for the comments. Gives me something to think about.
Ulrich - I didn't mean to imply that the ON4UN/W1FB approach didn't work.
It works fine but if you remove the drop wire then things change a bit.
Chuck's comment was on the mark. The tower will be resonant somewhere,
almost certainly not where you want it but you can't exactly run out with
your dikes and a prune a bit off but I guess you could fool around with some
top loading wires. In any case I will have to make arrangements to tune the
tower and make them permanent.
Since I haven't the willpower to leave a tower naked (without an HF Yagi on
top) just for 160 m, that means rotor cables, feedlines and such so I'd
best ground the tower. I will just have to drop 3 or more copperweld wires
down from the top (outside the tower) to an insulated ring near ground with
good tensioning. Intermediate insulating support rings will also be needed.
Can't have things flopping around in the breeze! In effect I will have a
base insulated tower which I can measure and tune to my hearts content. The
symmetry of the drop wires should reduce the variation as the beam is
rotated.
thanks again, 73, Rudy N6LF
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