Baluns
are not devices familiar to most engineers even if they have been in
the RF business for many years. Most have heard of them but few probably
really know what a balun is, how it works, and how it is used.
Admittedly,
it wasn't until maybe a decade ago that I ever even came into contact
with one - at least that I was aware of. Having spent most of my career
connecting cables and waveguide to pre-designed, pre-packaged components,
there was never a need to convert between balanced and unbalanced transmission
lines. The many analog circuits that I did always used ICs that had
single- or double-ended inputs and/or outputs so it was never necessary
to be concerned with the details. Now that I have been reading the ARRL's
QST magazine monthly for the last few years, an appreciation for and
understanding of baluns is really settling into the gray matter. I in
no way consider myself an expert now, but am pretty confident that at
least my visage won't assume that telltale deer-in-the-headlights look
before my eyeballs roll back. If you are a balun novice, there is probably
no better primer for your reading edification than Roy Lewallen's "Baluns:
What They Do and How They Do It" paper.
Note: The URL provided at the end of the article
is no longer valid. Use this one instead:
Some Aspects of the Balun Problem.
Posted December 4, 2013
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