Hi KC, His information is nothing really new, just stated differently. The standard modulation is 80% AM at 1 kHz, so the modulated field strength will be 1.8 times the unmodulated level. 61000-4-3 spells this out fairly clearly. I've never done a calibration of field uniformity with modulation on and I think that it is a bad idea since the field sensor may be effected by the modulation. That said, and after the chamber calibration is done, the power amplifier system _must_ be checked for clipping at the highest required forward power. I know of more than one commercial lab that passed field uniformity, but had clipped power amplifier output under modulation.
Respectfully, Brent DeWitt -----Original Message----- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of KC CHAN [PDD] Sent: Monday, September 23, 2002 7:57 PM To: emc-p...@ieee.org Subject: Radiated immunity test Dear All I just discussed with a supplier about the upgrade to 2GHz of the IEC61000-4-3, he showed me a document which says that the calibration of the field strength needs to be 1.8 greater then the required field, eg. for 10V/m, 18V/m is required for calibration to ensure the system can produce 10V/m with modulation. Since the deadline of testing above 1 GHz is coming for radio testing, this new requirement would definitely affect the decision of the system upgrade. Appreciate if anyone can advise more information about this. Best Regards KC Chan ------------------------------------------- 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: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" ------------------------------------------- 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: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
