In message <ofd2c30845.714f84dd-on652572d0.0047471b-652572d0.00489...@scmmicro.co.in >, dated Thu, 3 May 2007, [email protected] writes:
>In our ethernet device, by introducing series resistors of value 22 >ohms in the Tx / Rx signals we noticed reduction in the emission >levels. Reduction of emission in the ethernet harmonics (175, 200, 225, >250, 275, 300 & 350 MHz) is logical. At the same time we notice >reduction of emission in SDRAM clock harmonics also. (multiples of 59.9 >MHz). Why & how this happens and what to infer from this is not clear >to us. Welcome to the world of EMC! Such apparently inexplicable effects occur daily. There IS an explanation, entirely consistent with the laws of physics, but it may take 3 months and $10k to find it. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk There are benefits from being irrational - just ask the square root of 2. John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
