David, On a similar note I had heard that an EUT shelter might demonstrate a 6 dB variation between wet and dry conditions, or dirty vs. clean (pressure cleaned) condition.
Did the papers comment on wood properties? Perhaps identifying soft wood vs. hard wood, minerals absorbed during growth, wet vs. dry, or other "conditioning" situations? I have only seen a handful of labs, but they all had wooden tables (defacto standard for the times -- past?). I wonder if the standards were written around the convention of wooden tables? You've raised an interesting issue. Best regards, Don Umbdenstock Sensormatic > ---------- > From: Pommerenke, David[SMTP:[email protected]] > Reply To: Pommerenke, David > Sent: Thursday, November 01, 2001 4:15 PM > To: 'POWELL, DOUG'; EMC-PSTC (E-mail) > Subject: RE: EMC test table construction plans > > > Doug, > > For emissions and immunity you should not use any wood in the table. It > will > significantly (+/-2 dB up to 1 GHz for emissions , more above, +/-10 dB > for > immunity up to 1 GHz) change the test result. My experience has shown that > Styrofoam is basicly the best material. There are a couple of published > papers on this issue. As surface material the following worked out fine: > > - Foamed PVC (rather stiff, low dielectric constant due to the foamed > nature), maybe 4 mm thick. > > - PE sheet, maybe 2 mm thick. > > David Pommerenke > > > > -----Original Message----- > From: POWELL, DOUG [mailto:[email protected]] > Sent: Thursday, November 01, 2001 11:38 AM > To: EMC-PSTC (E-mail) > Subject: EMC test table construction plans > > > > Hello all, > > I plan to construct my own insulated EMC test table for a 5 meter chamber. > Seems simple enough to do and I could easily come up with something. I > thought I might first ask for input from those of you in the discussion > group who have experience or maybe even construction plans. Here are some > features I want: > > 1) I will be testing products that weight up to 200 Lbs (91 kg). > > 2) I want to minimize metalic fastners. > > 3) I would like to make it a pivoting table (not motorized). > > 4) Height is 80 cm. > > 5) The surface should be replacable if it gets badly worn or scarred. I'm > thinking of using hardboard. > > 6) Suggestions on length & width? > > -doug > > ----------- > Douglas E. Powell, Compliance Engineer > Advanced Energy Industries, Inc. > Mail stop: 203024 > 1626 Sharp Point Drive > Ft. Collins, CO 80525 > > 970.407.6410 (phone) > 970-407.5410 (fax) > mailto:[email protected] > ----------- > > > > _________________________________________ > > This message, including any attachments, may contain information that is > confidential and proprietary information of Advanced Energy Industries, > Inc. > The dissemination, distribution, use or copying of this message or any of > its attachments is strictly prohibited without the express written consent > of Advanced Energy Industries, Inc. > > ------------------------------------------- > 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. > > ------------------------------------------- > 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. > ------------------------------------------- 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.
