Today's heavy RF communications environment: Let's take the case of a cell phone having a minimum useful receive signal of -105 dBm and a PC that radiates a signal, in the 850 MHz cell phone band, that is 37 dBuV/m @ 3 meters. The PC is legal. Let's place the cell phone 1 meter from the PC. The cell phone antenna has an AF of 29 dB. The PC signal is -90 dBm at the cell phone receiver input. This can certainly bother the cell phone and cause it to change frequency. We have to move the cell phone over 6 meters away before it will ignore the PC.
Is anyone aware of any issues with cell phones and such? I realize these services have some frequency agility and perhaps that mitigates these issues. Dave Cuthbert Micron Technology From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Ken Javor Sent: Tuesday, August 02, 2005 7:14 AM To: emc-p...@ieee.org Subject: Re: Request for info on CE Mark penalties In the USA, FCC CE and RE limits for digital equipment were first derived as described in CBEMA Report ESC5/77/29. CE limits were based on measurements of victim radio sensitivity below 30 MHz, and RE limits were based on EIA specs for radio receiver sensitivity above 30 MHz. In other words, just as Mr. Woodgate states. I saw nothing about margins. Instead, the measurement methods were chosen to provide suitable accuracy. Thus, for instance, the 30 MHz break for CE/RE measurements. 30 MHz was stated to be the lowest frequency at which reasonably accurate RE measurements could be made at three meters. Analysis predicted that the 48 dBuV CE limit was sufficient to protect against RE below 30 MHz. The limits were placed just as Mr. Woodgate states, to minimize EMI complaints under typical but not all conditions. The 450 kHz lower end of FCC measurements encompassed the MW AM band plus the 455 kHz IF of AM band radios. In Europe, the lower frequency was 150 kHz because of 150 kHz - 300 kHz LW AM band usage. In this country we have LORAN navigation in use near the coasts, but it was deemed economically unsound to mandate that all office equipment meet CE limits to protect a few coastal radio victims. > From: rehel...@mmm.com > Date: Tue, 2 Aug 2005 02:49:02 -0500 > To: emc-p...@ieee.org > Subject: RE: Request for info on CE Mark penalties > > Dave, I have been trying for some time now to find out just exactly how > limits lines were derived. Can you point me to a study/report/data that can > show me (or more importantly, others here at work) just how the limits were > derived? No one seems to be able to. > > Bob Heller > 3M EMC Laboratory, 76-1-01 > St. Paul, MN 55107-1208 > Tel: 651- 778-6336 > Fax: 651-778-6252 > ========================= > > > > drcuthbert@micron > .com > Sent by: To > emc-p...@ieee.org <john_t...@bose.com> > <emc-p...@ieee.org> > cc > 08/01/2005 11:53 > AM Subject > RE: Request for info on CE Mark > penalties > > > > > > > > > > > John, > > the consideration of penalties is a form of consequentialist ethics that > focuses on "us". A higher form (in my opinion) is to focus on the > consequences to "the other." In this case, the other is society. As you > know, the EMC limits are not arbitrary; they are based on the interference > potential to EM communications. So one can consider that shipping a product > that exceeds the EMC limits could potentially harm society. > > One can take this one step further and consider that a product that is > under the EMC limits can still potentially harm society, but that it is not > as harmful as a product that exceeds the EMC limits. In this case we can > site rule based ethics by proclaiming that we meet the EMC rules and > therefore we have done all that we are required to do. These two > conflicting ethical positions could make for a long and interesting > discussion. > > Dave Cuthbert > Micron Technology > > > > From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Tyra, John > Sent: Friday, July 29, 2005 7:20 AM > To: emc-p...@ieee.org > Subject: Request for info on CE Mark penalties > > > > Hello everyone, > > > Does anyone have any good articles or website examples of the penalties for > non- conformance for the CE Mark. I especially need examples for EMC > violations to use to stress the seriousness and impact to business for > some non regulatory people here who need some convincing. > > > Thanks in advance for your help > > > > > > John Tyra > Manager Product Safety > > > Bose Corporation > The Mountain, MS-450 > Framingham, MA 01701-9168 > > > Phone: 508-766-1502 > Fax: 508-766-1145 > > > ---------------------------------------------------------------- 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 emc-p...@ieee.org > > > Instructions: http://listserv.ieee.org/listserv/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: > > > Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org > > > All emc-pstc postings are archived and searchable on the web at: > > > http://www.ieeecommunities.org/emc-pstc > > > ---------------------------------------------------------------- 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 emc-p...@ieee.org > > > Instructions: http://listserv.ieee.org/listserv/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: > > > Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org > > > All emc-pstc postings are archived and searchable on the web at: > > > http://www.ieeecommunities.org/emc-pstc > > ---------------------------------------------------------------- > 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 emc-p...@ieee.org > > Instructions: http://listserv.ieee.org/listserv/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: > > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > > http://www.ieeecommunities.org/emc-pstc > 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 emc-p...@ieee.org Instructions: http://listserv.ieee.org/listserv/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: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc 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 emc-p...@ieee.org Instructions: http://listserv.ieee.org/listserv/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: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
