> The tower is possibly too tall to be good on 160 (you didn't say the
> height), but maybe not.. Anything taller than half wave is going to have
> high angle lobes...
If the tower is to tall for 160 I strongly recommend and insulated cage
around the tower 1/4 lamda or slightly more. The tower itself should
probably float but you can experiment grounding it directly to the radial
system or at least have a choke to ground to deal with static charge
potentials. Thje cage if constructed properly will shield a good portion of
the inner (to tall) tower form the outside world, if that is the case.
Perhaps you ran into a case where the towers are very short for AM and if
that is the case a direct feed with a anti-reactance tuning cap is all you
will need.
It is also possible to detune (or electrically shorten) the structure with
the cage closer to the top but that can be a much more complicated and/or
difficult process to get working. So try the simple and easy things first.
And do consider, if the spacing is adequate a corner fed delta loop. I had
one on 80 meters suspended from a 300 footer in the early 80's and it was
unbeatable especially on receiving in a location over a big radials system
and surronded by salt water where Beverages could not work.
73,
Herb Schoenbohm, KV4FZ
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