[QCWA] baluns part 6

[Jeffrey D Angus]

9:1 current balun

(1)-uuu-(2)
(3)-uuu-(4)

(5)-uuu-(6)
(7)-uuu-(8)

(9)-uuu-(10)
(11)-uuu-(12)

Here we have three individual 1:1 current baluns.
We can connect them to make a 9:1 impedance
transformation at the same time as the balun
operation.

Connect (1) (5) and (9) to the coax center. (3) (7)
and (9) to the shield. (inputs are in parallel)
Connect the balanced load to (2) and (12) and tie
(4) and (6) together and (8) and (10). (outputs are
in series.)

For this to work properly, both of the transmission
lines have to be the correct impedance. In this case,
150 Ohm line.

Again, 150 / 3 = 50 (parallel inputs) and 150 * 3
= 450 (series outputs).

Now if you're going to wind of these for yourself,
you can use two types of two wire transmission lines.

A pair of #16 AWG magnet wire using a piece of #18
as a spacer works out to 150 Ohms. Interestingly
enough, #16 AWG lamp cord available at Home Depot is
fairly close as well.

Jeff-1.0
wa6fwi