Just printed a copy (6o some pages) and reading – looks very good:
A Ham’s Guide to RFI, Ferrites, Baluns, and Audio Interfacing
Revision 5a 5 Jun 2010 by Jim Brown K9YC
Audio Systems Group, Inc. http://audiosystemsgroup.com
The basis of this tutorial is a combination of my engineering education, 55 years in ham radio, my work as vice-chair of the AES Standards Committee working group on EMC, and extensive re- search on RFI in the pro audio world where I’ve made my living. That work is documented in tech- nical papers and tutorials that can be downloaded from the publications section of my website.