On Tue, 6 Feb 2007 11:25:38 -0500, "Hopkins, Michael J." <[email protected]> wrote:
> There is currently a corrigendum circulating to clarify this issue, but > the way it's currently written, it probably won't survive..... ... > In either case, most also agree that the calibration should be done for > each line output of the CDN, independently (one at a time) with a 50 ohm > load. Otherwise you can't insure that each output is operating > correctly...... When all lines are tied together, this DO change.. An > alternative might be to verify that each line by itself is correct, AND > that when tied together in common mode, the output is still the same, > but it won't be..... Thank you very much for the valuable information. In my own opinion, calibration for each single line might not enough to ensure consistency between test equipment, as it seems there are generators / CDNs which have acceptable output waveform when driving a single line but the waveform significantly degrade when driving multiple lines. In the other hand, requring common mode verification could make such existing generators / CDNs outdated, and maybe we need to pay lot of money for new test equipment... I think this is a difficult problem to solve, but I hope it could be clarified in near future. By the way, may I ask one more question on this standard? Figure 8 (example of a test set-up for rack mounted equipment) says that cable length between the coupling device and the EUT is 1m. Does it actually mean 1m, or is it intended to be 0.5m? Regards, Tom Tomonori Sato <[email protected]> URL: http://homepage3.nifty.com/tsato/ - 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 ______________________________________________________________________
