Hello Vitaly, I found it more useful to use the OATS for initial measurements with the measurement antenna spaced at a close distance to the EUT than to use the shielded room for ballpark measurements. The reflections in the shielded room caused too much of a variation in the emissions to guess which emissions to evaluate and which ones could be skipped.
Once a base line is established on the OATS, the shielded room can be useful for a - b comparisons. This way you can see the profile of the product without the camouflage of the ambients and see at a glance if any other emissions popped up when you beat down the emission of interest. We were fortunate enough to justify a ferrite lined compact chamber for immunity work. This chamber gets used about 90% of the time for precompliance emissions work prior to going to the OATS, even though it was justified for immunity. We really get our money's worth. The reflections are much less than a shielded room and ballpark results for initial measurements can be observed. Good luck, Don Umbdenstock Sensormatic > ---------- > From: Gorodetsky, Vitaly[SMTP:[email protected]] > Reply To: Gorodetsky, Vitaly > Sent: Thursday, December 14, 2000 3:05 PM > To: Emc-Pstc (E-mail) > Subject: Shielded Room > > > Dear Colleagues, > > I have been asked to comment on the scope of use/capabilities of shielded > rooms (2-3m x 2m). I would appreciate if you would share your opinion on > the usefulness of Radiated Emissions tests, validity of data, > effectiveness > of establishing an emissions baseline information of approved products for > future design changes. Any recommendations for improving the usefulness? > Please do not limit yourself to the above and feel free to expand. > > Any comments, advice will be greatly appreciated. > > Vitaly Gorodetsky > Compliance Engineer Direct: (818) 678-3840 > Canoga Perkins Corp. Main: (818) 718-6300 > 20600 Prairie Street FAX: (818) 678-3740 > Chatsworth, CA 91311-6008 e-mail: > [email protected] <mailto:[email protected]> > > The suitability of this information for making decision is solely with the > reader > > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > To cancel your subscription, send mail to: > [email protected] > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Jim Bacher: [email protected] > Michael Garretson: [email protected] > > For policy questions, send mail to: > Richard Nute: [email protected] > > ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected]
