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AMfone's Online AM Handbook => Hints and Kinks => Topic started by: Steve - K4HX on October 14, 2015, 08:44:49 PM

Title: Common-Mode Chokes by Chuck Counselman, W1HIS
Post by: Steve - K4HX on October 14, 2015, 08:44:49 PM
Common-Mode Chokes1
Chuck Counselman, W1HIS


This article tells what common-mode chokes are, why and where to use them, and how
to make ones that work well, at minimal cost both in time and in dollars.

In the HF hamshacks that Iíve visited, the background noise level heard on most HF bands (especially the low bands) could be reduced by more than an S-unit by means of common-mode choking. In some cases (which I could name but wonít, to avoid embarrassing my friends) I was able to reduce the received noise level by four or five S-units. I reduced my own received noise level on the low bands by even more.
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