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

This balun was made with single ferrite core, (Jaycar L0-1234) wired using single strand Cat 5 UTP wire. The winding ratio is 8 turns to 20 turns. 50 ohm primary is 3 x 8 turns, wired in parallel. The 300 ohm secondary is formed by winding 2 x 10 turns in series, (grounding the centre tap) giving 20 turns overall. This gives a truer balanced to unbalanced impedance transformer. The picture here shows the balun core ready for testing. The two single wires are the 300 ohm secondary. The others are the 50 ohm primary with the larger one being the common ground.
6 to 1 Balun
The schematic

6 to 1 Balun schematic
VSWR output

Here's the VSWR from 1 to 100MHz. The various markers are as shown.
6 to 1 vswr
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