On Tue, 6 May 2003 17:35:49 +0200, "Franck GALVIN" <[email protected]> wrote: >I perform conducted or radiated emission test with HP8594EM spectrum >analyser or HP8656A receiver. >To not have measurements errors I must enter correction factors (antenna >or LISN, cable and other .). >My questions are: >1/ When you enter data to antenna factors for example, you write >''frequency'', ''amplitude'' and what about ''frequency scale'' (log or lin) ? >2/ Does frequency scale depend of correction type (cable, amplifier, >antenna, LISN, transient limiter.)?
I'm familiar with the 8590-series analyzers, so I'll comment about that one. The 'Frequency Scale' feature allows you to accurately specify a limit line/correction factor that is linear with log(frequency) by using only two data points. Without this feature, you have to interpolate many data points between the start and stop frequency for an accurate limit line. The scale mode has no benefit if the limit line/correction factor is flat with frequency. The obvious example is to draw the CISPR 11/CISPR 22 Class B Conducted emission limit line from 0.15-0.50MHz. The limit line entries using the 'log' scale mode: 0.15 66dBuV SLOPE 0.50 56dBuV FLAT The limit line entries using the 'linear' scale mode (2dB increments in amplitude): 0.150 66dBuV SLOPE 0.191 64dBuV SLOPE 0.243 62dBuV SLOPE 0.309 60dBuV SLOPE 0.393 58dBuV SLOPE 0.500 56dBuV SLOPE As far as correction factors are concerned, use the scale mode that best fits your accuracy/data point requirements. 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: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] 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
