How the transformer is wound also makes a big difference. For integrated magnetics, changing jack vendors can really affect the spectrum. Although the difference is not dependable...
Regards, Rob -----Original Message----- From: John Woodgate [mailto:[email protected]] Sent: Wednesday, September 29, 2010 4:04 PM To: [email protected] Subject: Re: [PSES] EMI issue with Ethernet In message <[email protected]>, dated Wed, 29 Sep 2010, "ce-test, qualified testing bv - Gert Gremmen" <[email protected]> writes: >Most of the time the problem is that the ground point centertap > >of the Ethernet transformer is insufficiently grounded. This may well be a practical finding, but ground really has no function for a balanced transmission line, which is what Ethernet (and several other techniques) is based on. Ground at one end is never at the same potential as ground at the other end, especially at RF. - ---------------------------------------------------------------- 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]>
