Dear Members, Thank you very much to those whe have commented. FYI. We found out the data discrepancy was caused by a test fixture/board (support test commands to set up channels and power level) and the length of power lead (from EUT to DC power supply).
Best regards, Grace On 6/18/08, Grace Lin <[email protected]> wrote: Dear Members, I need your help to find out what may be wrong/inaccurate for the power spectral density measurement per 47 CFR 15.247. I was told the data I took was about 6 dB higher. I follow the measurement procedure (PSD Option 1) for the digital transmission system, published by the FCC ( https://fjallfoss.fcc.gov/oetcf/kdb/fo ms/FTSSearchResultPage.cfm?id=21124&switch=P). The antenna port of the transmitter was connected to the R&S ESU40 receiver (in spectrum analyzer mode). Data was taken with and without 30dB attenuators to avoid overload issue. RBW=3kHz, VBW=10kHz, Span=1.5MHz, Sweep=500s. I couldn't figure out where might be wrong. Thank you and look forard to your instructions. Best regards, Grace - ---------------------------------------------------------------- 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 [email protected] 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 [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
