In a message dated 96-11-27 12:11:27 EST, you write:
<< I found the same problem with a 100' tower and a 10/15/20 Xmas tree 10
years ago. Could never get the 80 to really play. I then grid dipped the
tower and found it was 1/4 wave reasonant on 1450KHz!
Im wondering now if anyone has tried moving the 80M feed up the tower and
use isolated elevated radials?
>>
The answer here is a current breaker to electrically isolate a part of the
tower, which will raise the resonant frequency above 16o or 80 meters,
depending on which band you want.... you could put the current breaker below
the elevated radials to remove the bottom of the tower for rf on 80... or,
you can put the current breaker on the upper part of the tower to raise the
resonant frequency of the shunt fed base...
Denny
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