I used to manage a commercial EMI test lab in So. Ca. in the mid 90's. At that time our 10m OATS was located at one end of an asphalt covered parking lot of a small shopping center. The ground plane consisted of an electrically conductive wire mesh buried a few inches under the asphalt. At that time we performed the NSA measurements using the discrete 27 frequency point method of ANSI C63.4-(1992) and we passed every time (during the 3 years I was there). However, I don't know if we would still have passed had we used the swept frequency method instead. We never tried it. Hope this is helpful. Sincerely, Manny Barron EMC Engineer Northrop Grumman Corp. Electromagnetic System Laboratory San Jose, California web: www.ngc.com
_____ From: [email protected] [mailto:[email protected]] On Behalf Of Grasso, Charles Sent: Friday, April 27, 2007 8:14 AM To: Michael Heckrotte; EMC PSTC - Post message (E-mail) Subject: RE: OATS Ground Plane Embedded in Asphalt Hi Mike, I didn’t see any responses to this .. I’ve been out for a while. The EMC Society (in its early years) did a *lot* of work on test sites for emissions. Basically they concluded that putting any sort of cover on the groundplane was not a good idea. Numerous papers were published and can be found on CDROM published by the EMC Society. To date I have not seen any publication to contradict that. Dan Heirman was (at least in my memory) at the forefront of this effort. Best Regards Charles Grasso Compliance Engineer Echostar Communications Corp. Tel: 303-706-5467 Fax: 303-799-6222 Cell: 303-204-2974 Pager/Short Message: [email protected] <BLOCKED::mailto:[email protected]> Email: [email protected] _____ From: [email protected] [mailto:[email protected]] On Behalf Of Michael Heckrotte Sent: Wednesday, April 25, 2007 2:34 PM To: EMC PSTC - Post message (E-mail) Subject: OATS Ground Plane Embedded in Asphalt Hi, If anyone has experience with building an OATS with a layer of asphalt on top of the ground plane, regarding the effect of asphalt thickness on NSA, please contact me off line. Best Regards, Mike We have moved to our new Fremont location as of January 18, 2007. Please note new address and phone numbers below. Michael Heckrotte Engineering Manager, CCS 47173 Benicia Street, Fremont, CA 94538 Main: (510) 771-1000 Direct: (510) 771-1121 Fax: (510) 661-0885 [email protected] - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [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 Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________ - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
