Steve: Your experience mirrors mine. The transformer type of voltage
Baluns have caused a lot of trips up the tower.
The coiled coax versions are somewhat better, but I've had several
problems with interwinding voltage breakdown on these.
The ferrite sleeve current balun has never failed me.
I've read the efficiency reports, and while I can't verify it,
that may be a problem. But, personally, I'd rather loose a few
watts from heat than to have to fight the other battles.
There is really no reason to purchase a current balun. Amidon
Associates sells ferrite sleeves with 1/4" and 1/2" inside diameter.
The 1/4 inch versions work great with the small 50 ohm coax.
I've used the silver plated, teflon insulated stuff made for
microwave at 1500 watts with no problem And, the fit neatly
inside of a 1/2" PVC pipe for protection.
The 1/2" works well with RG-8AU, RG-214, etc and can be
just slipped over the coax at the feed point and taped in place.
At any rate, failure has not occurred here.
de KL7HF
> > I've burned up BN-86s and had problems with the W2DU type baluns.
Come to
> > think of it,
> > over the years, baluns have been a dependable source of problems!
I've
> > finally given up
> > and gone back to what I used to use and what you are wondering about:
a
> > choke made of
> > several turns of coax. I've never had any problems with that simple
and
> > effective
> > device. Why do we keep buying baluns?
> >
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