In a message dated 10/22/2003 3:32:48 PM Pacific Standard Time, tom@xxxxxxxxxxxxx writes: In my experience, which I'm sure is not as broad as many who are contributing to this thread, is the cables were the big problem. Any noise on the ground, power or signals that were connected to the cables was radiated. This was much higher than anything on the board. ************ The above is a true statement for many (if not most) cases as radiated emissions increase with the square of frequency for common-mode radiation, but not for all EMI problems (either extenally detected or internally experienced....with resultng unacceptable performance). Loop circuits/antennas radiate only in proportion to frequency and are therefore not as big a problem at higher frequencies (where most of this discussion applies). As we all know, the generation of CM noise involves several other causes that have been discussed at length on this forum. Knowledge of ALL these phenomena (and their prevention) is what establishes the need for SI Engineers. Mike Michael L. Conn Owner/Principal Consultant Mikon Consulting *** Serving Your Needs with Technical Excellence *** ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu