Hi Lou: Try checking the AC input wiring to the power supply, and verify that it doesn't have loops across the power supply. Magnetic fields from the transformer may be high, and excessive wire length acts as a magnetic pickup.
1) Are the parameters you posted for the conducted emission limits accurate? I tried plotting them, and got a big discontinuity at 0.15MHz. 2) Is there any change in the conducted emission test setup below 0.15MHz? 3) Does the GOST radiated emission standard specify an E-field (dipole, biconical, log periodic, etc.) antenna below 30MHz? Below 0.15MHz? Or are there magnetic loop antennas for some of the test ranges? I have a hard time imagining E-field measurements below 30MHz at a 3m distance. ---- Patrick Lawler [email protected] On Fri, 21 Dec 2001 10:19:22 -0800, you wrote: <snip> >The requirements for EMC of radio equipment in Russia (as well as in several >other CIS countries) are set by the standard GOST 30429-96 (Electromagnetic >Compatibility of technical equipment. Man-made noise from equipment and >apparatus used t6ogether with service receiver systems of civil application. >Limits and test methods), according to this standard the following >measurement must be done. >1. Conducted Emissions >Frequency range Limits, dB(uV) >0.009 MHz - 0.15 MHz U = 90 - 28.9lg(f/0,01) (Quasi-peak) >0.15 MHz - 0.5 MHz U = 66 - 22.7lg(f/0,15) (Quasi-peak) >0.5 MHz - 6 MHz U = 54 - 12.97lg(f/0,5) (Quasi-peak) >6 MHz - 30 MHz U = 40 (Quasi-peak) >30 MHz - 100 MHz U = 48 (Quasi-peak) 40 (Average) > >This test is done looking at the emissions from the 220 V power cables, >using a LISN >2. Radiated Emissions >Frequency range Limits, dB(uV/m) >0.01 MHz - 0.15 MHz E = 60 - 20.4lg(f/0.01) >0.15 MHz - 30 MHz E = 37 - 7.39lg(f/0.15) >30 MHz - 100 MHz E = 36 - 21.0lg(f/0.30) >100 MHz - 1000 MHz E = 25 + 20.0lg(f/100) > >According to GOST 30429-96 this test is done at 3 meters in frequency range >0.01MHz - 30 MHz and at 1 meter in frequency range 30 MHz - 1000 MHz in the >screen room. ------------------------------------------- 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: Michael Garretson: [email protected] Dave Heald [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
