This brings up the question of "How much margin is necessary to account for manufacturing variations?" And I guess that depends upon if periodic sampling is performed or not. So, how much margin would be considered to be acceptable if no periodic sampling is performed?
Richard Woods Sensormatic Electronics Tyco International From: andy.wh...@nokia.com [mailto:andy.wh...@nokia.com] Sent: Friday, October 31, 2003 11:37 AM To: da...@alisonlabs.com; emc-p...@majordomo.ieee.org Subject: RE: Window of Uncertainty The FCC does not allow any units (sold on the marketplace) to be 'above' the FCC limits. It is therefore prudent to ensure that 'all' finished production units comply with the FCC limits taking in to account manufacturing build tolerance/variability, product design tolerance/variability and final laboratory measurement uncertainty. Which basically leads to ensuring that your product has a designed in emissions 'margin' that will provide compliance for units leaving the production floor. In my experience during initial product development EMC testing/qualification you have to pursue to attain as much 'margin' as possible. To let a product through certification with a minimalist margin at the beginning of marketing product launch will only make subsequent product design changes/updates much more difficult to certify. Andy _____________________________ Andy White EMC Engineer Nokia Mobile Phones San Diego, CA Tel 858 831 4534 andy.wh...@nokia.com _____________________________ This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
