Hi all, Actually I was using a good ole Spectrim Analyser so I sidestepped the windowing issue/software issues altogether.
What I was(am)trying to do was match the max voltage as measured on a scope with the value as measured on a SA. I first calibrated myslef using a known source - a sine wave. The amplitudes fell in just as theory predicted. Encouraged, I then probed the Vcc plane on a product I was working on and was not so happy!! Any ideas? From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Saturday, July 26, 2003 4:19 PM To: Charles Grasso; Emc-Pstc Subject: Re: Q on Correlation of Votage ripple with a Spectrum Analyser I presented a paper on that very subject about a decade ago at one of the EMC T&D magazine EMC symposia. I used a Fluke Scopemeter and some FFT software that came with it. The Fluke interfaced to the PC through an optically isolated RS-232 protocol. It worked quite well from a pre-compliance or troubleshooting point-of-view. You could use time windowing to separate the signals deriving from leading and falling edges >from the signals deriving from the pulse itself. I used LISNMATE and LISNMARK mode separation devices to show that the rising/falling edge signals were common mode, while the pulse itself generated differential mode signals. > From: "Charles Grasso" <cgrassospri...@earthlink.net> > Reply-To: "Charles Grasso" <cgrassospri...@earthlink.net> > Date: Sat, 26 Jul 2003 16:18:36 -0700 > To: "Emc-Pstc" <emc-p...@ieee.org> > Subject: Q on Correlation of Votage ripple with a Spectrum Analyser > > > Hi All, > > > Has anyone tried correlating the voltage ripple > as seen on a scope with the amplitudes measured > on a Spectrum Analyser? > > I tried doing that the other day with ..umm. minimal > success. I think that due to the comples convoltions > that would have to occur when FFT'ing an irregular > voltage shape. > > Charles Grasso > Echostar Communications. > > ------------------------------------------- > 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 > 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
