[TowerTalk] How to best determine the need for a balun

[David Robbins K1TTT]

> Another thing that is interesting is pretty much everyone
> proposing small elevated counterpoise systems has included a
> warning buried in the text that the feedline needs
> decoupled, but everyone ignores it. When I was measuring
> elevated radial systems I found adding a choke or current
> balun increased the FS of the elevated system by as much as
> 1dB or more, and I wasn't looking for a worse case
> condition.

What kind of geometry was this with??  What about a case where the
feedlines of a 4-square with elevated feed points is in the same plane
as the radials??  Would the outside of the shield be any different than
any other radial in this case?

> If the idea of using a current balun is troublesome, get a
> magic marker out and write the word "isolation choke" where
> it used to say "balun". Then it won't confuse the RF. ;-)

good idea, I have always hated the idea of calling a glob of ferrites or
a coil of coax a 'balun'.

David Robbins K1TTT
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