In message <of46c65765.1d7bd346-on65257515.0055dedf-65257515.0057e...@scmmicro.co.in >, dated Thu, 4 Dec 2008, kbalasubraman...@scmmicro.co.in writes:
> Still I see variation in the results between the testing on any 2 >days for the same piece of device with same support equipment. And >testing the same set up in another lab puzzled me many times. >Frequencies appearing in one lab will not be seen in the other, level >will differ more than 10 dB at same frequency between the labs, both >the labs are accredited. Ssssh! We don't talk about such things. This is, after all, the Century of the Emperor's New Clothes, and not only as regards EMC. (;-) However, provided we never let the metrologists know, we can carry on using procedures that actually have a remarkable level of uncertainty, simply because they work in practice. The ultimate, and only real, test of an EMC measurement method and the associated limit(s) is that they result in an acceptably low level of field complaints of interference due to the phenomenon concerned. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk Either we are causing global warming, in which case we may be able to stop it, or natural variation is causing it, and we probably can't stop it. You choose! John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - 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 <emc-p...@ieee.org> 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 <emcp...@ptcnh.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
