Hi, I am not so sure. A true (frequency selective) receiver acc. to CISPR 16 is ok. A spectrum analyzer with preselector might be ok. Ambients is not the problem but rather potentially overloading RX front-end (intermodulation free measurement dynamic range may be 30-40dB with analyzer!). Imaging there are broadband and narrow band emissions present at the same time but with very different amplitudes. In this situation and using just a spectrum analyzer( no preselector) the receive antenna at 3m is the only "frequency selective device" before the mixes. Moreover most noise-figures of analyzers cause difficulties towards 1 GHz. CISPR 22 e.g. requires the noise to be -6dB below RE limits. Naturally this is very serious at d=10m. Generally speaking, there are mostly 2 schools of users: EU=>receiver, US/Asia => mostly analyzer. This is my experience from many audits.
kind regards Dr. Diethard Hansen EES President, Principal Consultant, Trainer US Senior NARTE certif. EMC Eng. 001937NE EMC+Automotive+Telecom QM+techn. EA-Auditor Euro EMC SERVICE (EES) Dr.-Ing. D. Hansen POB 64, Bahnhofstr.39, CH-8965 Berikon 2, Switzerland, Swiss VAT (Mwst.)No.:323214 tel./fax: +41 566 33 73 81 German mobile phone: +49(0)1736015909 www.euro-emc-service.de [email protected] (mailto:[email protected]) Consulting+Seminars+R&D-Projects Marketing+CE-Testing+ww.Audits From: [email protected] [mailto:[email protected]]On Behalf Of Ralph McDiarmid Sent: Friday, March 26, 2004 8:45 PM To: [email protected] Subject: RE: Semi-anechoic chamber & a preselector Does anyone in the group have experience with the need for a RF preselector used in a 3m chamber? I suspect it is really necessary more for an OATS where out-of-band strong ambients could present a problem for the attenuator/mixer in a SA. Thanks, Ralph McDiarmid, AScT Compliance Engineering Group Xantrex Technology Inc. This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ieee-pses.org/ 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] 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.ieee-pses.org/ 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] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
