[RFI] Experience with RF-INQUIRY Hi-Q Chokes?

[Tom Rauch]

> Has anybody experience with these things? I have some minor RFI problems
> here at home and they might be related to common mode. I already have a
> coil of coax below my beam (which is on top of the house). Can anybody
> confirm these 50 db? Sounds a lot to me.

Sounds like a lot to me also.

I can make receiving CM choke systems that are over 40dB at one frequency
range, but I doubt anyone can do that over wide bandwidths without a
pi-section and isolated grounds.

See http://www.w8ji.com/Baluns/balun_test.htm for some tests related to
1.8MHz.

73 Tom


>
> I somehow have the feeling that inside that "Hi-Q Choke" there is only a
> piece of coax with some ferrite beads. Just a typical W2DU baluns on
teflon
> coax which you get for 20 EUR here in DL. The RF-Inquiry ones cost about
> 120-180 EUR (depending on power).
>
> Unfortunately there is not much information about these products on the
> web. Can somebody here in the mailing list shed some light on this topic?
>
> Another question. Can I use a W2DU 1:1 balun in my transmission line just
> right after the amp and expect some filtering of common mode currents on
> the coax cable? Would this help to "clean" up the coax? Or do I have to
use
> 2 baluns. One at the input and one at the output?
>
> Thanks in advance!
>
> 73
> Christian, DL6KAC
> --
> mailto:c.buenger at gmx.ch
> fax2mail: +49 25 61 / 9 59 42 99 20
>
> _______________________________________________
> RFI mailing list
> RFI at contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>