Skip to main content
  1. Equipment/
  2. Accessories/

Homebrew common mode choke

My selfmade common mode choke placed into a neat plastic case with BNC connectors.

So this is basically a 140-43 toroid with 9 turns of RG174 connected to BNC connectors.

It works very well and I have made two measurements recently.

The maximum loss is on 10m around 0.2dB
It attenuates common mode current with more than 20dB

I find this okay for now but I still wonder if this can be made any better (maybe 30dB attenuation?). Would I benefit from even more attenuation?

I will probably find out on another day.