Charles, There is another article by Bill Ritenour that summarizes the Dockey paper and provides more detail about the CM phenomena in PWB's, along with several possible 'fixes'. http://www.devicelink.com/mem/archive/98/10/007.html -Dave Barr Charles Grasso wrote: > To all interested parties: > > In recent threads a paper by R. Dockey was recommended as > light reading. Unfortunately due to copyright reasons > this paper cannot be made freely available. However, > the basis of that paper - Asymmetrical Mode Radiation from > MultiLayer Printed Circuit Boards - has no such restrictions > and it can be downloaded from the RMCEMC website > http://www.ieee.org/rmcemc . > > This paper demonstrates that a simple trace over a ground plane > can produce emissions that fail the FCC Class B specifications. > This paper was originally offered as a way to measure emissions. > The purpose of this was to answer the question: > > "I welcome measurements from others that supports the statement that traces > over planes are significant sources of EMI. So far, no one has presented > such evidence. Lacking such evidence, how can anyone make such claims?" > > and to offer a measurement methodology.This paper shows > that changes in the dimensions of the structure > can and will affect the emissions profile. > > Enjoy... > > Charles Grasso > RMCEMC - Chair. > > ------------------------------------------------------------------ > 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 > ------------------------------------------------------------------ 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