[snip]
It has been shown (by W8JI, among others) that mismatch is NOT a
contributor to heating in a choke balun. Heating in a current balun is
proportional to the square of the common mode current.
[snip]
Jim,
Then why do chokes burn up?
For instance, the RF Store has a pretty comprehensive
selection of current baluns and voltage baluns.
They make pretty sure that each and every advertising
page and individual model ads say something about the
SSB - vs - RTTY ratings, and explain further that the
chokes heat up.
Are you telling us that for the weight and consistency
of the core material the heating, and as you described,
Common Mode, (current on the shield at some point?),
is the culprit?
Does this mean that there is some material available
that will not heat up and melt down despite a longer
duty cycle in digital applications?
Without purchasing a 35 pound choke in an iron box that
probably won't hang too well in the middle of a 160 meter
OCF, are there any practical solutions instead of ladder line?
Respectfully,
Hal
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