This is a updated collection of easy to build projects for radio amateurs and swl's.
Have fun.
73 John

Wednesday, October 16, 2013

Broad band 1:1 current/choke balun

In search of a no nonsence 1:1 balun i came up with this easy to build unit. It offeres a almost flat swr curve from 1 to 30 MHz  as you can see in the plot. Use 10 turns of side by side1 mm enamelled copper wire on a 4C65 or FT140-61 toroid . Teflon tape was used on the toroid but this is not essential.

SWR plot of the balun bridged with a 50 Ohm resistor.
Disclaimer:I'm not responsable for any damage due to reproduction of my projects.


Solar data and HF conditions logbook