On 9/4/2021 2:48 PM, jerry wrote:
31-mix is supposed to be the hot ticket for HF common mode
chokes. One turn through one core is supposed to be 98 ohms at 5MHz. So
four cores should give me about 400 ohms, which should give a worthwhile
attenuation in a 50 ohm system. Thanks for the references.
I'm the guy that did the original work on this, beginning in 2003, when
#31 was a brand new mix. I got five of the first #31 toroids from the
pre-production run, a few months after I suggested that they would be
quite useful. My first publication was a paper to a 2005 international
meeting of the Audio Engineering Society, of which I'm a Fellow. First
publication to the ham world was RFI-Ham.pdf in 2007. And you are
mistaken about the value of four cores at HF. Study that paper. It's a
tutorial on how RFI happens and how chokes work.
73, Jim K9YC
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [email protected]
