RE: Microwave Oven Interference with 2.4Ghz Wireless LAN
Hi Gherry: Just remember that when you pull back on the yoke (stick), the houses get smaller, but if you keep pulling back they get bigger again. John From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Pettit, Ghery Sent: Monday, October 06, 2008 2:24 PM To: Conway, Patrick R (Houston); Brian O'Connell; emc-p...@ieee.org Subject: RE: Microwave Oven Interference with 2.4Ghz Wireless LAN Nothing much of interest. It's about as interesting as getting a sports car up to about 75 mph and pulling back on the wheel. Not much happens. Now, do that in a small airplane and pull back on the wheel. Yippee! From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Conway, Patrick R (Houston) Sent: Monday, October 06, 2008 2:20 PM To: Brian O'Connell; emc-p...@ieee.org Subject: RE: Microwave Oven Interference with 2.4Ghz Wireless LAN ...circling back to an old thread: What would happen if we placed 8 access points in a circle around some popcorn? YouTube here we come! Best Regards, Patrick. p.con...@hp.com From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Brian O'Connell Sent: Monday, October 06, 2008 4:00 PM To: emc-p...@ieee.org Subject: RE: Microwave Oven Interference with 2.4Ghz Wireless LAN Recently we added two new food blasters to the lunch room and noted that some office areas no longer had reliable network connect. Installed some isolation transformers between building mains and the food blasters - no more complaints from the sales/accounting dweebs, or whatever they do. Also noted that some of the power to the lunch room does not have a separate ground wire - uses the metal conduit, which probably does not help much. As for the specific ID of these iso transformers, hmmm... we no longer make this particular model. But I am going to upgrade my tin-foil hat, as I very much suspect that the space aliens are using the 2.4GHz carrier to link our brains to the NSA computers... luck, Brian From: emc-p...@ieee.org [mailto:emc-p...@ieee.org]On Behalf Of don_borow...@selinc.com Sent: Monday, October 06, 2008 1:27 PM To: emc-p...@ieee.org Cc: brian_ku...@lecotc.com Subject: Re: Microwave Oven Interference with 2.4Ghz Wireless LAN Except for rebuilding the break rooms with foil-lined dry wall, metal flooring, screened windows, filtered power, waveguide-beyond-cutoff ventilation grills, and RF tight doors, I don't know there is much for a solution. I was told that in one major Boeing plant, communications as 2.4 GHz is all but impossible -- there are microwave ovens scattered around the various break rooms running off of all three phases of the electrical power (120/208 volts Y); and due to variety of manufacturers, generating RF during both polarities of each phase. In other words, continuous 2.4 GHz RF. Except for specialize industrial units, I don't think you will find microwave ovens running at any other frequency. Don Borowski Schweitzer Engineering Labs Pullman, WA, USA Kunde, Brian brian_kunde@leco tc.com To Sent by: emc-pstc emc-p...@ieee.org emc-p...@ieee.org cc Subject 10/06/2008 01:02 Microwave Oven Interference with PM2.4Ghz Wireless LAN I have just received and interesting call from our IT guys in our production facility. They have installed a 2.4Ghz wireless LAN system in our production and stock room areas, which is a huge area, and which includes 13 Access Points and a couple dozen wireless devices such as bar code readers, computers, and printers. They discovered that they are having a major interference problem which they have narrowed down to the Microwave Ovens in the two break areas. Evidently, Microwave Ovens run at 2.45Ghz. It would be very difficult to remove the ovens or to move the break areas. Have any of you experts have experience with this issue? Any suggestions? Are new ovens better then older ones? Are the microwave ovens that run at a different frequency? Would it help to try and shield the ovens better? Please help. The Other Brian LECO Corporation Notice: This communication may contain confidential information intended for the named recipient(s) only. If you received this by mistake, please destroy it and notify us of the error. Thank you. - 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/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:emc-p...@daveheald.com All emc-pstc postings are
RE: Microwave Oven Interference with 2.4Ghz Wireless LAN
It's a typical example of international frequency regulators (ISO/ERC) failing. Who the heck decided it was a good idea of allocating the 2.4 GHz band (ISM frequency) to Wireless LAN's ? Of course the actual decision was made by the standardization committee that wrote IEEE (!!) 802-b/g (any family?)to make sue of a licencse free band) but this by lack of a suitable free frequency. Or at least they were thinking that a LAN would never approach a MicroWave oven. Good luck that these devices operate on a rectified AC power without any capacitance, so they switch off every half period, during which the LAN has the time to transfer some data. Many GHZ go unused currently, reserved to some non-operating system or defense applications that may or may not be used one day. Take for example the 2900-3100 Mhz band could have been allocated at the time to short range devices in a similar way as 2400-2483.5 has been allocated today. But regulation agencies are always too late in recognizing the market... Gert Gremmen Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens John Shinn Verzonden: dinsdag 7 oktober 2008 5:46 Aan: 'Pettit, Ghery'; 'emc-p...@ieee.org' Onderwerp: RE: Microwave Oven Interference with 2.4Ghz Wireless LAN Hi Gherry: Just remember that when you pull back on the yoke (stick), the houses get smaller, but if you keep pulling back they get bigger again. John From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Pettit, Ghery Sent: Monday, October 06, 2008 2:24 PM To: Conway, Patrick R (Houston); Brian O'Connell; emc-p...@ieee.org Subject: RE: Microwave Oven Interference with 2.4Ghz Wireless LAN Nothing much of interest. It's about as interesting as getting a sports car up to about 75 mph and pulling back on the wheel. Not much happens. Now, do that in a small airplane and pull back on the wheel. Yippee! From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Conway, Patrick R (Houston) Sent: Monday, October 06, 2008 2:20 PM To: Brian O'Connell; emc-p...@ieee.org Subject: RE: Microwave Oven Interference with 2.4Ghz Wireless LAN ...circling back to an old thread: What would happen if we placed 8 access points in a circle around some popcorn? YouTube here we come! Best Regards, Patrick. p.con...@hp.com From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Brian O'Connell Sent: Monday, October 06, 2008 4:00 PM To: emc-p...@ieee.org Subject: RE: Microwave Oven Interference with 2.4Ghz Wireless LAN Recently we added two new food blasters to the lunch room and noted that some office areas no longer had reliable network connect. Installed some isolation transformers between building mains and the food blasters - no more complaints from the sales/accounting dweebs, or whatever they do. Also noted that some of the power to the lunch room does not have a separate ground wire - uses the metal conduit, which probably does not help much. As for the specific ID of these iso transformers, hmmm... we no longer make this particular model. But I am going to upgrade my tin-foil hat, as I very much suspect that the space aliens are using the 2.4GHz carrier to link our brains to the NSA computers... luck, Brian From: emc-p...@ieee.org [mailto:emc-p...@ieee.org]On Behalf Of don_borow...@selinc.com Sent: Monday, October 06, 2008 1:27 PM To: emc-p...@ieee.org Cc: brian_ku...@lecotc.com Subject: Re: Microwave Oven Interference with 2.4Ghz Wireless LAN Except for rebuilding the break rooms with foil-lined dry wall, metal flooring, screened windows, filtered power, waveguide-beyond-cutoff ventilation grills, and RF tight doors, I don't know there is much for a solution. I was told that in one major Boeing plant, communications as 2.4 GHz is all but impossible -- there are microwave ovens scattered around the various break rooms running off of all three phases of the electrical power (120/208 volts Y); and due to variety of manufacturers, generating RF during both polarities of each phase. In other words, continuous 2.4 GHz RF. Except for specialize industrial units, I don't think you will find microwave ovens running at any other frequency. Don Borowski Schweitzer Engineering Labs Pullman, WA, USA Kunde, Brian brian_kunde@leco tc.com To Sent by: emc-pstc emc-p...@ieee.org emc-p...@ieee.org cc Subject 10/06/2008 01:02 Microwave Oven Interference with PM2.4Ghz Wireless LAN I have just received and interesting call from our IT guys in our production facility. They have installed a 2.4Ghz wireless LAN system in our production and stock room areas, which is a huge area, and which includes 13 Access Points and a couple dozen wireless devices such as bar code readers, computers, and printers. They discovered that they are having a major interference problem which they have narrowed down to the Microwave
Re: Microwave Oven Interference with 2.4Ghz Wireless LAN
In message FCA549BE3ECF9D4CB8CB8576837EA48905322B@ZEUS.cetest.local, dated Tue, 7 Oct 2008, Gert Gremmen g.grem...@cetest.nl writes: It's a typical example of international frequency regulators (ISO/ERC) failing. Who the heck decided it was a good idea of allocating the 2.4 GHz band (ISM frequency) to Wireless LAN's ? Of course the actual decision was made by the standardization committee that wrote IEEE (!!) 802-b/g (any family?)to make sue of a licencse free band) I don't think those bodies are responsible (or not entirely). Frequency allocations are agreed internationally by ITU (but are not necessarily agreed on a world-wide basis, but by regions). but this by lack of a suitable free frequency. Or at least they were thinking that a LAN would never approach a MicroWave oven. Good luck that these devices operate on a rectified AC power without any capacitance, so they switch off every half period, They have full-wave rectifiers, so it's the 2.45 GHz that switches off when the rectifier output voltage is too low, but the mains current doesn't switch off. On the other hand, the switching-off creates a comb of sidebands around the oscillation frequency at frequency separations equal to the mains supply frequency and its harmonics. So it's difficult indeed to avoid the emissions by selecting a particular carrier frequency (or frequencies) within the band for LAN use. during which the LAN has the time to transfer some data. Many GHZ go unused currently, reserved to some non-operating system or defense applications that may or may not be used one day. Take for example the 2900-3100 Mhz band could have been allocated at the time to short range devices in a similar way as 2400-2483.5 has been allocated today. But regulation agencies are always too late in recognizing the market... Like the US Senate, the maxim is 'with all deliberate speed'. The decisions have to take in very many interests and be as 'future-proof' as possible. -- 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.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/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:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
[no subject]
Hi John et al, Well the switch-on/switch off effects are wideband, but are time domain limited (transients), and do not have a great impact on network transmission capacities. My point is that the lack of available license free frequencies have lead to excessive use of this small band (2400-2485 MHz) not taking into account the interference properties of the original application for microwaves. (That is why ITU reserved this slot in the first place as ISM). The small bandwidth has also lead to the problem of useable channel allocations for wireless lan ( 1,6,11 of ther available 1-14) and the limited number of on-the-air networks in one areas to be only 3. At my daughters study place, a room in a popular neighbourhood in Utrecht a network scan learns me that there are 17 wireless LANS in the (close) neighbourhood. (most allocated to channel 11) I would not be surprised to find 17 microwave ovens also. No wonder that she has frequent internet connection problems. Regards, Ing. Gert Gremmen ce-test, qualified testing bv - 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/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: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
only for test, please ignore this mail.
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IEC60225-5 surge test impedance?
We are being asked to run this test and don't have the standard. The voltage is 5kV and the energy is 0.5J but rather than do the calculus involved I thought I'd just ask for the specified source impedance. Thanks in advance Jim Eichner Sent from Blackberry Wireless - 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/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:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: IEC60225-5 surge test impedance?
500 Ohms Don MacArthur Compliance Engineer General Dynamics Itronix Corporation 12825 E. Mirabeau Parkway Spokane Valley, WA 99216 ph: 509-742-1342 fax: 509-742-1672 email address: don.macart...@gd-itronix.com This email message is for the sole use of the intended recipients and may contain GDC4S confidential or privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not an intended recipient, please contact the sender by reply email and destroy all copies of the original message. From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Jim Eichner Sent: Tuesday, October 07, 2008 7:41 AM To: emc-p...@ieee.org Cc: Fred Kracke; Jim Eichner Subject: IEC60225-5 surge test impedance? We are being asked to run this test and don't have the standard. The voltage is 5kV and the energy is 0.5J but rather than do the calculus involved I thought I'd just ask for the specified source impedance. Thanks in advance Jim Eichner Sent from Blackberry Wireless - 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/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:emc-p...@daveheald.com 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/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:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: IEC60225-5 surge test impedance?
Thanks Don. Too bad our generator/CDN only has 2 or 12 ohms! Jim Eichner, P.Eng. Compliance Engineering Manager Xantrex Technology Inc. phone: (604) 422-2546 mobile: (604) 418-8472 e-mail: jim.eich...@xantrex.com web: www.xantrex.com Confidentiality Notice: This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. From: MacArthur, Don [mailto:don.macart...@gd-itronix.com] Sent: Tuesday, October 07, 2008 7:54 AM To: Jim Eichner; emc-p...@ieee.org Cc: Fred Kracke Subject: RE: IEC60225-5 surge test impedance? 500 Ohms Don MacArthur Compliance Engineer General Dynamics Itronix Corporation 12825 E. Mirabeau Parkway Spokane Valley, WA 99216 ph: 509-742-1342 fax: 509-742-1672 email address: don.macart...@gd-itronix.com This email message is for the sole use of the intended recipients and may contain GDC4S confidential or privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not an intended recipient, please contact the sender by reply email and destroy all copies of the original message. From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Jim Eichner Sent: Tuesday, October 07, 2008 7:41 AM To: emc-p...@ieee.org Cc: Fred Kracke; Jim Eichner Subject: IEC60225-5 surge test impedance? We are being asked to run this test and don't have the standard. The voltage is 5kV and the energy is 0.5J but rather than do the calculus involved I thought I'd just ask for the specified source impedance. Thanks in advance Jim Eichner Sent from Blackberry Wireless - 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/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:emc-p...@daveheald.com 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/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:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: IEC60225-5 surge test impedance?
Is it possible to insert a resistor between surge generator and CDN to provide the correct impedance? Here is one source of high-voltage, power resistors. http://www.caddock.com/Online_catalog/high_voltage/high_voltage.html Ralph McDiarmid, AScT Compliance Engineering Group Xantrex Technology Inc From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Jim Eichner Sent: Tuesday, October 07, 2008 10:14 AM To: emc-p...@ieee.org Cc: Jim Eichner; Fred Kracke Subject: RE: IEC60225-5 surge test impedance? Thanks Don. Too bad our generator/CDN only has 2 or 12 ohms! Jim Eichner, P.Eng. Compliance Engineering Manager Xantrex Technology Inc. phone: (604) 422-2546 mobile: (604) 418-8472 e-mail: jim.eich...@xantrex.com web: www.xantrex.com Confidentiality Notice: This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. From: MacArthur, Don [mailto:don.macart...@gd-itronix.com] Sent: Tuesday, October 07, 2008 7:54 AM To: Jim Eichner; emc-p...@ieee.org Cc: Fred Kracke Subject: RE: IEC60225-5 surge test impedance? 500 Ohms Don MacArthur Compliance Engineer General Dynamics Itronix Corporation 12825 E. Mirabeau Parkway Spokane Valley, WA 99216 ph: 509-742-1342 fax: 509-742-1672 email address: don.macart...@gd-itronix.com This email message is for the sole use of the intended recipients and may contain GDC4S confidential or privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not an intended recipient, please contact the sender by reply email and destroy all copies of the original message. From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Jim Eichner Sent: Tuesday, October 07, 2008 7:41 AM To: emc-p...@ieee.org Cc: Fred Kracke; Jim Eichner Subject: IEC60225-5 surge test impedance? We are being asked to run this test and don't have the standard. The voltage is 5kV and the energy is 0.5J but rather than do the calculus involved I thought I'd just ask for the specified source impedance. Thanks in advance Jim Eichner Sent from Blackberry Wireless - 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/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:emc-p...@daveheald.com 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/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:emc-p...@daveheald.com 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/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:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: IEC60225-5 surge test impedance?
On 10/7/2008, Ralph McDiarmid wrote: Is it possible to insert a resistor between surge generator and CDN to provide the correct impedance? Here is one source of high-voltage, power resistors. http://www.caddock.com/Online_catalog/high_voltage/high_voltage.html Hi Ralph: It is common practice to insert an external resistor in series with the output of a surge generator to reduce the short-circuit current. In fact, some standards call out different values of external resistance in their tests. The resistor will influence the short-circuit current waveform, so you may need to pay attention to that. You must be very careful about the power rating and construction of any resistors you add. The resistors must be able to handle the surge power, and they must be non-inductive (not wire wound). Interestingly, one of the best types of construction for this application is the old carbon-composition type, but these are getting hard to find. As long as the resistor construction you use is non-inductive, you can achieve whatever surge tolerance you need by connecting several resistors in parallel. Joe Randolph Telecom Design Consultant Randolph Telecom, Inc. 781-721-2848 (USA) j...@randolph-telecom.com http://www.randolph-telecom.com http://www.randolph-telecom.com/ - 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/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: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
