Clamp attenuation calibration. The calibration proposed in CISPR16 amd to meet the attenuation is peformed using a "jig" construction of the required lengthe and 2 connectors and a wire trough the clamp. All 50 ohm. The test wire is 4mm diameter and floats at 90 mm above the jig bottom. This way all type of clamps can be tested. Connectors are N-type. The length can be adjusted to the clamp. The jig flanges are 100 x 120 mm For accurate measurement use 2 attentuators of 10 dB at each end. The proposition number is Cispr A 424/CD Attenuation must be better then 15 dB (30 - 1000 MHz) The author forgot to specify in which direction but bidirectional is assumed. The official name is CMAD Common Mode Absorption Device. (before John makes one himself ;<))
Regards, Gert Gremmen ce-test, qualified testing Rotterdam, The Netherlands http://www.ce-test.nl From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Chris Maxwell Sent: woensdag 29 januari 2003 21:14 To: Pettit, Ghery; neve...@attbi.com; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Indeed, a very good point! I wonder what is meant by the "50 Ohm system" does that mean a function generator with 50 Ohm output impedance, 50 Ohm cable and a 50 Ohm load? (This could be simulated nicely by connecting a function generator to a 50 Ohm spectrum analyzer input using 50 Ohm cable) If that were the case, then calibration would be relatively easy. If that were the case, then my initial calculation would also have to be adjusted to take into account the total "non-ferrite" impedance which would be closer to 150 Ohms...Yielding a calculated Zf of 693 Ohms. I previously assumed that a 50Ohm system had a total "pre-ferrite" impedance of 50 Ohms, which gave me a Zf of 231 Ohms. Of course, the standard says 15dB "minimum"... so you could just use 1000 Ohms (at all frequencies, remember) and be done with it! It probably still wouldn't cost $300. Before anybody goes out and buys "ferrites ala carte", remember; I'm not on any CISPR commitees; I'm just throwing out a little bit of Math and some assumptions and suggesting that this could be done. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | > -----Original Message----- > From: Pettit, Ghery [SMTP:ghery.pet...@intel.com] > Sent: Wednesday, January 29, 2003 2:09 PM > To: Chris Maxwell; Pettit, Ghery; neve...@attbi.com; emc-p...@majordomo.ieee.org > Subject: RE: EN55022:1998 + A1:2000 > > Chris, > > You can indeed make your own, but my bet is that A2LA or NIST NVLAP > inspectors will want to see calibration data, not calculations. > > Now, if we just had a published calibration technique... > > Ghery > > 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 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: davehe...@attbi.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
