In my earlier response, I assumed the measurement would be made with modulation off. The peak would be 5.1 dB higher with 80% modulation, but what is measured on the spectrum analyzer would, as you point out, depend on the bandwidth settings. For true RMS power meters, the measurement would be 1.1dB higher with modulation on. To measure the induced current with a spectrum analyzer, without the modulation affecting the reading, I set the RBW to 300Hz or lower (for a 1kHz modulation frequency). Some spectrum analyzers don't have bandwidths that low, and for others (like the HP 859x series) it is an option. Bob Richards, NCT.
Javor <ken.ja...@emccompliance.com> wrote: Presumably you have the 80% modulation. If you use a spectrum analyzer with peak detection and a bandwidth larger than the required modulation bandwidth you will capture the peak of the modulation envelope, which would be 120 mA. In dB, that is less than 1 dB error, within the uncertainty of a spectrum analyzer measurement. But your EUT and AE both need to have a common mode short to ground to get this level of current flowing. Seems odd. - ---------------------------------------------------------------- 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 email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
