In a message dated 10/23/2003 7:07:38 PM Pacific Standard Time, tom@xxxxxxxxxxxxx writes: Were the resonances predicted radiate directly or did the resonances conduct energy to other elements which radiated the energy? How did you determine the contribution from the microstrip vs. the other radiators in a complete PC? The resonances were based on my analysis of the chip package size, material (Alumina, Er=9.5 to 10.5)), and associated propagation rate. There was energy passage to the PCB traces and planes via the power and ground pins of the package, plus direct radiation from the package. Adding a needed heatsink to the top of the package and grounding it at the four corners reduced the emissions by 6 dB, but did not eliminate all of the EMI. The package resonant peaks were still detectable in the radiated emissions data at 10 meters. (I had recommended a similar improvement to Motorola/Phoenix for their Power PC models a few months earlier....very successful also). The internal package corrective actions I recommended to AMD (that resolved many problems) are proprietary and will not be disclosed further. Note that this activity was immediately prior to the first release of the highly successful AMD K6 microprocessor. Mike Michael L. Conn Owner/Principal Consultant Mikon Consulting Cell: (408)821-9843 *** 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