Oh yeah, any harmonic of 125 Mhz can be quite annoying, but if the PCB layout is right, it all goes away.
- Bill Indecision may or may not be the problem. --- On Fri, 11/21/08, Sterner, David (NY80) <[email protected]> wrote: From: Sterner, David (NY80) <[email protected]> Subject: RE: 375MHz from 10/100Base-T To: "Knighten, Jim L" <[email protected]>, [email protected] Date: Friday, November 21, 2008, 4:35 PM 375 MHz is a third harmonic for 100BaseTX. The primary frequency for 100BaseTX is 125 MHz (the extra 25 covers Ethernet overhead). _ Honeywell David W. Sterner Quality Assurance Engineering 2 Corporate Center Drive - Suite 100 P.O. Box 9040 Melville, NY 11747 Phone: (516) 577-2321 Fax: (516) 577-3540 [email protected] <http://www.honeywell.com> [email protected] <http://www.IEEE.LI> Editor, The Pulse IEEE 05888136 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Knighten, Jim L Sent: Friday, November 21, 2008 4:17 PM To: [email protected] Subject: 375MHz from 10/100Base-T I am experiencing a robust radiated emission at 375 MHz from a rack containing various computing hardware. This seems to come from Ethernet 10/100Base-T switches, cables, etc. Have others experienced this frequency with Ethernet hookups? Jim __________________________ James L. Knighten, Ph.D. EMC Engineer Teradata Corporation 17095 Via Del Campo San Diego, CA 92127 858-485-2537 - phone 858-485-3788 - fax (unattended) - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ 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]> - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ 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]> - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ 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]>
