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View Full Version : RF choke balun on ladder/ribbon line.



Jarikeen
Sat 11th Oct 2008, 11:51
You know how you can RF choke coax with ferrite sleeves as a form of balun, can the same principle be used with ladder or ribbon line (the 300 - 450 ohm) by using the flat ferrite bars sometimes used with computers?

m0bov
Sat 11th Oct 2008, 18:13
No, since the ladder is part of the antenna system and it will affect the currents going along the cable. When you RF choke wire or ladder with a clip on choke, it stops RF travelling along it.

If you don't want the cable to radiate then use coax and a 1:1 balun, don't use a clip on choke, they are used for EMC purposes.

Jarikeen
Sun 12th Oct 2008, 23:46
Thanks for that, I thought as much, but wasn't sure. I was thinking of instances like the end feed zepp and J poles (same thing really), where it is common to choke the coax. Cheers