> >So what happens to your operation once the bead
> >balun gets hot and experiences the "big bang" ?
> >
> >Does your vswr go up? Does the antenna efficiency
> >become lousy? Maybe the driven element is no
> >longer balanced? How do you know down in the
> >shack that the balun is now NG?
Not sure who is asking, as several of the messages going around have been
snipped.
I have caught the inexpensive bead Baluns heating and stopped transmitting.
You can watch the reflected power on a Bird rise as they heat up. When they
go bang, they blow out the middle of the bead stack and destroy the outer
housing. There is no longer a connection with the antenna and you have
parts in the yard. Using the proper ferrite mix must be important for the
designer. Having a properly matched antenna and not attempting to use it
someplace where it is not resonant is important for the user. If you have
done your part in building and measuring well, then you run high power, you
will find out in a hurry if the Balun designer did their part.
73
Greg K9ZM
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