Topband: Tower insulator thickness?

[Donald Chester]

>I'm planning on using some insulating material under BPC25 and BPC55 Rohn 
>base plates (and around the pier pin in the center) so the towers may be 
>series-fed on 160.
>
>Is 7/16-inch thick enough for this purpose?

I think you would end up with a pretty good capacitor from tower base to 
ground.  Plus, what if a lightning surge breaks down the thin sheet of 
insulating material?

I would opt for a real base insulator.  If you can't find a used one removed 
from a broadcast tower, you could fabricate one from a large electric power 
insulator.  I have seen ones about 6" in diameter and anywhere from 6" to 
over 12" tall, with metal castings with tapped screw holes at each end.

-k4kyv