[TowerTalk] Needed: Balun and Unun text by W2FMI

[Tom Rauch]

I concur with Tom's evaluation -- the later editions are
better technically
-- I have both the original and later editions.>>

The edition I kept was third printing 2002 by CQ
Communications.

The only real snafu's I've found in that printing are with
the evaluation of a dipole and why it needs or doesn't need
a balun (the theory is incorrect and the test of a dipole
isn't a valid test) and some statements that a single core
can be used to make a 4:1 current balun using a pair of
transmission line mode transformers. MFJ actually built a
4:1 balun that way and the balance is very poor. As a matter
of fact it really doesn't act like a balun, let alone a
current balun.

The exception is a conventional primary-secondary mode
transformer. That type of system CAN be wound on a single
core in any ratio, since it is in effect just an isolation
transformer. True transmission line mode transformers like
Sevik describes, other than a 1:1 ratio, cannot be placed on
a single core without screwing up balance.

73 Tom