Re: Question about OATS
From: emcp...@aol.com Reply-To: emcp...@aol.com List-Post: emc-pstc@listserv.ieee.org List-Post: emc-pstc@listserv.ieee.org List-Post: emc-pstc@listserv.ieee.org List-Post: emc-pstc@listserv.ieee.org Date: Wed, 18 Jun 2003 20:13:25 EDT > Also, there is a chain-link fence running parallel with the proposed site, > but the fence is just outside the ellipse. Would there be any problems > with site attenuation? The fence may not be an important factor if it is not 'too' high. Ken is right, first do a simple site survey. I suggest you use a roll of chicken wire (mesh) to check out the site first. (ANSI C63.7-1992 page 5.) To be realistic, try to keep the reference plane within +/- 4.5 cm flat. However all things being said, that will largely depends on the soil's mechnical condition. By right :-) only low bushes are acceptable in the immediate 'vicinity' of the ellipse (obstruction free area). Another way is to do a NEC (MOM) simulation to see if the fence have a significant contribution NSA of the OATS. :-) Good luck. Tim Foo 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Question about OATS
The ellipse is the area clear of any reflecting obstruction above ground. I don't see a need to tie the ground plane extent to the ellipse area. Although theoretically keeping the ellipse clear should suffice to meet the NSA curve, I wold be concerned about the fence near the perimeter, regardless of its orientation relative to the major axis. Before risking the time and expense of building the OATS, why not try a quick site attenuation at the place you plan on building the OATS, and another ten meters further away if that is possible. I don't think height surveys are necessary here, the main thing is to see how many dB different the planned site attenuation is from the one further away. From: emcp...@aol.com Reply-To: emcp...@aol.com List-Post: emc-pstc@listserv.ieee.org List-Post: emc-pstc@listserv.ieee.org List-Post: emc-pstc@listserv.ieee.org List-Post: emc-pstc@listserv.ieee.org Date: Wed, 18 Jun 2003 20:13:25 EDT To: emc-p...@majordomo.ieee.org Subject: Question about OATS Hello, I'm building an open area test site, and have some questions about the ellipse and ground plane. I'm following ANSI C63.7:1992. I have used several OATS and done site attenuation before, but this is the first time building one from the ground up. I'm building a 10 Meter OATS with a 14 foot turntable. Figure 1 in ANSI C63.7 says that the minor diameter of the ellipse shall be 17.3 Meters and the major diameter shall be 20 meters for a 10 meter site. For the ground plane, Table 1 in ANSI C63.7 says for a 10 meter site, the width shall be 12 meters and the length shall be 15.3 meters. The corners of the ground plane will be outside the ellipse. Is this ok, or should the ground plane be smaller, to fit inside the ellipse? What would be the minimum ground plane size I could use for this 10 meter site with a 14 foot turntable? Also, there is a chain-link fence running parallel with the proposed site, but the fence is just outside the ellipse. Would there be any problems with site attenuation? I can alter the ellipse so the site is not exactly parallel with the fence. (Antenna would be somewhat diagonal to the fence) Would that help avoid any problems? Thanks in advance for any input you may have. Tim Pierce EMC Engineer
Question about OATS
Hello, I'm building an open area test site, and have some questions about the ellipse and ground plane. I'm following ANSI C63.7:1992. I have used several OATS and done site attenuation before, but this is the first time building one from the ground up. I'm building a 10 Meter OATS with a 14 foot turntable. Figure 1 in ANSI C63.7 says that the minor diameter of the ellipse shall be 17.3 Meters and the major diameter shall be 20 meters for a 10 meter site. For the ground plane, Table 1 in ANSI C63.7 says for a 10 meter site, the width shall be 12 meters and the length shall be 15.3 meters. The corners of the ground plane will be outside the ellipse. Is this ok, or should the ground plane be smaller, to fit inside the ellipse? What would be the minimum ground plane size I could use for this 10 meter site with a 14 foot turntable? Also, there is a chain-link fence running parallel with the proposed site, but the fence is just outside the ellipse. Would there be any problems with site attenuation? I can alter the ellipse so the site is not exactly parallel with the fence. (Antenna would be somewhat diagonal to the fence) Would that help avoid any problems? Thanks in advance for any input you may have. Tim Pierce EMC Engineer
Military standards
Hi folks, Where can I find (buy) the following standards: AECP 1 Edition: 2: Mechanical environmental conditions to which materiel intended for use by NATO Forces could be exposed. AEP-5: NATO standard engine laboratory test for gas turbine engines and diesel and spark ignition engines. ATP 45 (B): Reporting nuclear detonations, biological and chemical attacks, and predicting and warning of associated hazards and hazard areas. I assume some of them might be classified, but thanks for all kind of input. Best regards Amund Westin, Oslo, Norway 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: CBEMA/ITI curves
Ged, After a little research, I found some history of the CBEMA/ITIC curve. This was developed by the CBEMA's ESC-3 Working group to provide information for the IEEE STD 446 (Orange Book). Within the Orange Book, I have the 1987 edition so there may be some changes, section 3.11 - Data Processing - looks at the tolerance of voltages for ITE equipment. There is additional reference to IEEE C84.1, which looks at numerous different types of power systems. I hope that this helps. Thanks, Bryan. From: gd...@ncht.trent.nhs.uk [mailto:gd...@ncht.trent.nhs.uk] Sent: Friday, June 13, 2003 8:29 AM To: emc-p...@majordomo.ieee.org Subject: CBEMA/ITI curves I am interested in the CBEMA curves for susceptibilty of electronic devices to power supply voltage variations/disturbances. I have found by internet search the original CBEMA curves - which I believe were published in a US Standard FIPS-94 (1983) - and the revised CBEMA/ITI curves circa 2000. These curves are based upon 120V/60Hz power supply; can anyone advise whether similar curves have been produced for 230V/50Hz supplies, or how the applicabiilty of the orginal 120V/60Hz curves may be compromised when considering supply at 230V/50Hz? Also, the 120V/60Hz curves appear to be widely quoted but any limiting assumptions made in their production rarely discussed - can anybody advise, or point me in the direction of more background information? Many thanks, Ged Dean, Nottingham City Hospital ** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been swept by MIMEsweeper for the presence of computer viruses. NCHT ** 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. 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.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
New EU Member States
I received information that the Czech Republic has until 2005 to completely implement the Packaging and Packaging Waste Directive. Does anyone know if the 10 new member states to be added next year have any time frames for conforming with the various Directives, in particular the LV, EMC and RTTE Directives? Richard Woods Sensormatic Electronics Tyco International 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Automotive Audio Standards
Hello in List Land, I have 3 questions: 1. Can anyone tell me what EMC standards apply to automotive audio equipment, specifically amplifiers? 2. For those non-governmental requirements, can you tell me a source for these standards? 3. Is there a list, similar to emc-pstc, for automotive (or automotive audio) types? Any help is appreciated, off-line responses requested. Best regards to all, Scott Douglas email: sdoug...@ptcnh.net 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
