John Sebolt wrote:
..You might get by with just putting the balun in front of almost any tuner,
but keeping ground floating. Zack Lau's "QRP Transmatch for Balanced Lines" in
Qrp Classics (and the Handbook?) is just a regular L net with the balun in
front, and floating from ground. Something doesn't feel quite right about
that, if you REALLY want a true balanced line, but it's something to try.
I believe that there is a similar article in one of the antenna
compendiums that goes through a bit more analysis (than Lau's article) of this
type of design (balun in front of unbalanced L-network). Although the L-network
looks unbalanced, the balun forces it to be balanced - and using one inductor,
rather than two, greatly simplifies the design.
I don't know if this really works - in a quick read-thru of the article
it seemed that something was missed in the theoretical discussion - I really
should go back and dig into it more deeply. But I agree with John, give it a
try, it is a MUCH simpler design.
- Jeff, WA6AHL
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