[QCWA] Baluns part 2

[Jeffrey D Angus]

Continuing on with voltage type baluns, these are the same
type of transformer used since Tesla came up with the idea
of alternating current.

Earliest forms of voltage baluns were the classic link type
coupling tank coils made by Barker and Williamson. Taking
the several thousand ohm push pull output from a pair of
amplifier tunes and converting it to a lower impedance for
feeding antennas.

After WWII the availability of coax tended to make systems
designed for unbalanced low impedance (50 ohms).

Unfortunately, despite the introduction of coax, dipoles
still had to be fed with balanced feeds for optimum
performance.

Air-Dux used to make a bifilar wound air core coil. This was
used as one would expect. A primary connected to the coax
and a secondary connected to the feed point of a dipole.

A 1:1 turns ratio that resulted in a 1:1 impedance ratio.

Stay tuned for more.

Jeff-1.0
wa6fwi