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4 to 1 balun.
The completed balun core - wired.

This balun was made with two ferrite cores, (Jaycar LF1258)wired using Cat 5 UTP wire. The winding ratio is 6 turns to 12 turns. 50 ohm primary is 6 turns. The 200 ohm secondary is formed by adding 3 turns to either end, giving 12 turns overall. The picture here shows the balun core ready for testing. The two single wires are the 200 ohm secondary. The two inner soldered pairs are the 50 ohm primary.
4 to 1 Balun
The schematic

6 to 1 Balun
So, what does the balun impedance look like?

Here's the Smith chart showing the impedance from 1 to 50MHz. The marker is at 30MHz.
4 to 1 smith chart
and the return loss?

Here's the VSWR from 1 to 50MHz. The marker is at 30MHz.
4 to 1 vswr
Almost finished...

Here you can see the balun in the box. What you can't see is the glue on the other side of the balun providing additional support between the balun and the case.
Balun in the box
The finished project.

Giving your project a printed label gives it a more professional look and finish!
4 to 1 Balun
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