RE: Painting the ferrite tiles on a Semi-anechoic chamber
Hello Ahmad, Our chamber installer suggested rolls of white refrigerator magnets. This has been used in some major installations with the customer's logo applied. As it is magnetic material, not part of the original installation, I suspect that it would have some impact, perhaps a wash in the end. The good news is, if you don't like it for any reason, it comes off of the chamber wall as easy as it comes off of the refrigerator. The ordering info is Master Magnetics Inc. The Magnet Source 607 South Gilbert Castle Rock, CO. 80104 888-293-9399 Kim DeLong x128 White Vinyl Magnet Sheet 24 wide x 50' long x 0.020 thick P/N ZG2024GW50MG Hope this helps. Regards, Don Umbdenstock Tyco Safety Products -- Sensormatic -- From: Fallah, Ahmad[SMTP:afal...@ciena.com] Reply To: Fallah, Ahmad Sent: Tuesday, December 03, 2002 8:36 PM To: emc-p...@majordomo.ieee.org Subject: Painting the ferrite tiles on a Semi-anechoic chamber Group, Has anyone attempted to paint the inside of an anechoic chamber (i.e., paint the ferrite tiles)? Some chambers have partial or no coverage of the ferrite tiles by the absorber cones, which result in darkening the chamber's inside. The idea is to paint the ferrite tiles in a light color to brighten up the inside. Thanks, Ahmad Fallah --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: Conducted Line Emissions
Hello Dan, You have 2 interesting options open to you, but you do not have enough information for either. The FCC revised their Part 15 rules for conducted emissions this September essentially adopting CISPR 22, measuring in both QP and Ave. The product needs to pass both limits to establish compliance. However, the new rules are not mandatory until July 2004 for new designs (production and importation must include the new rules by July 2005). Under the old rules, the product is measured with a QP detector and compared to the limits. If an over-limit condition is observed, one then applies the broadband test. The broadband test compares the signal measured with an Average detector to the signal measured with the QP detector. If the Ave level is more than 6 dB below the QP level, the signal is considered broadband and a 13 dB relaxation is allowed. Also note that under the old rules, the spectrum of concern is 450 kHz to 30 MHz compared to 150 kHz to 30 MHz for the new rules. For the data that you presented, no one can tell if the product passes or fails because there is no QP data. Both the new and the old standard require a QP measurement. Hope this helps. Regards, Don Umbdenstock Tyco Safety Products -- Sensormatic -- From: Dan Pierce[SMTP:dpie...@openglobe.net] Reply To: Dan Pierce Sent: Thursday, November 07, 2002 4:04 PM To: emc-p...@majordomo.ieee.org Subject: Conducted Line Emissions File: Dan Pierce.vcfFile: Pages from Line conduction.pdf Greetings: I am looking for proof that I can use the averaged value for emissions rather than the peak value. Attached is a chart that I was given by an Asia test site that told me I failed. According to my past experience, I believe that the average power is what I should be concerned about. Similar to radiated emissions right? Thank you. Daniel J. Pierce Sr. Design Engineer OpenGlobe, Inc. (An Escient Technologies Affiliate) 6325 Digital Way Indianapolis, IN 46278 mailto:dpie...@openglobe.net P: (317) 616.6587 F: (317) 616.6587 --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: requirement for surge and EFT
Hello George, EN 55024:1998, the title of Table 4 is Immunity, input a.c. power ports (including equipment marketed with a separate a.c./d.c power converter). The table includes surge and fast transients. Seems like this issue must have come up before. Hope this helps, Don Umbdenstock Tyco Safety Products -- Sensormatic -- From: George Stults[SMTP:george.stu...@watchguard.com] Reply To: George Stults Sent: Thursday, October 10, 2002 4:13 PM To: 'emc-p...@ieee.org' Subject: requirement for surge and EFT Hello Group, I am talking with an offshore manufacturer who is suggesting that their CE marked ITE gear does not have to pass Surge and EFT since it runs off 12Vdc, normally provided by an AC/DC power supply, which is supplied in the same package. They suggest that the AC/DC power supply, but not the ITE, has to pass Surge, etc. I'm sure that the whole system has to pass, but I don't know chapter and verse to quote. I suppose the scope should be spelled out in EN55024 but I don't have a copy of it, yet. Thanks in advance. George Stults --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: Measurement below 30MHz
Hello KC, I cannot comment on the Japanese standard; I can comment on the FCC regulations. The FCC does allow 40 dB/decade below 30 MHz; they also allow a different roll-off established by measuring at 2 points along a radial. The resultant may be different than 40 dB/decade, depending on the frequency and the antenna. A basic loop antenna at 13 MHz will likely produce less than 40 dB/decade. If the antenna is wound in a field canceling manor, you might measure something greater than 40/dB per decade. Best regards, Don Umbdenstock Tyco Safety Products Sensormatic -- From: KC CHAN [PDD][SMTP:kcc...@hkpc.org] Reply To: KC CHAN [PDD] Sent: Thursday, June 06, 2002 10:36 PM To: emc-p...@majordomo.ieee.org Subject: Measurement below 30MHz To all I just came across a Japanese standard about a RFID product at 13.5 MHZ, it says that measurement of FCC from 30m to 3m will need to take the 20dB conversion(ie 20dB/decade) into account. But I found a statement from FCC part 15.31(f)(2) that at frequency below 30 MHZ, 40/decade extrapolation factor shall be used. I just want to clarify which we should use for measurement below 30MHz, 20dB/decade or 40/decade? Thank you KC Chan --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: SV: Question about EN61000-4-3:2002
Hello Sandy, I just received a copy and scanned through it. As you had indicated, the core of the standard is the same. The calibration methodology is the same as EN 61000-4-3 1996. Annexes have been provided for rationale for the choice of modulation for tests, a section on the use of anechoic chambers with a discussion on problems caused by ferrite lining of chambers and possible solutions, and a discussion of illumination by the independent windows method. If you test short range devices, EN 301489 is the product standard that specifies radiated immunity testing parameters, including the requirement above 1 GHz. This standard specifies the level and modulation. IEC 61000-4-3 2002 provides the guidance for calibration, set up, execution (with alternatives) and reporting. Best regards, Don Umbdenstock Tyco Safety Products TEPG -Sensormatic -- From: Sandy Mazzola[SMTP:mazzo...@symbol.com] Reply To: Sandy Mazzola Sent: Wednesday, May 29, 2002 5:21 PM To: emc-p...@majordomo.ieee.org; am...@westin-emission.no Subject: Re: SV: Question about EN61000-4-3:2002 File: Sandy Mazzola.vcf.txt Amund, Thank you for your response. Taking a quick look at the 2002 version the only changes I could tell were to do with were some information on using anechoic chambers above 1 GHz and alternative illumination techniques for frequencies above 1 GHz. Have a great day Sandy Mazzola Santo Mazzola Regulatory Engineer Symbol Technologies Inc 1 Symbol Plaza Holtsville, N. Y. 11742-1300 Phone: (631) 738-5373 Fax: (631) 738-3318 E-mail: mazzo...@symbol.com am...@westin-emission.no 05/29/02 04:30PM Sandy, I have just seen parts of the 2002 version. It seems to be dealing with the technique to calibrate the field strength above 1GHz. There are also some requirements regarding the measuring chamber. Best regards Amund Westin, Oslo/Norway -Opprinnelig melding- Fra: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]Pa vegne av Sandy Mazzola Sendt: 28. mai 2002 21:51 Til: emc-p...@majordomo.ieee.org Emne: Question about EN61000-4-3:2002 To all, I noticed that an EN61000-4-3:2002 just came into effectivity. Can anyone give me the short concise comparison of EN61000-4-3:2002 versus EN61000-4-3:1997. Thank You Santo Mazzola Regulatory Engineer Symbol Technologies Inc 1 Symbol Plaza Holtsville, N. Y. 11742-1300 Phone: (631) 738-5373 Fax: (631) 738-3318 E-mail: mazzo...@symbol.com --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: Compact Chamber Calibration clarification
A possible point of clarification, step e does not say what the +/- 3 dB is referenced to. I assumed it was of the mean, though it does not explicitly say that. Thoughts? Best regards, Don Umbdenstock -- From: UMBDENSTOCK, DON Sent: Friday, May 17, 2002 11:38 AM To: 'EMC Forum' Subject: Compact Chamber Calibration Hi All, I read the standard EN 61000-4-3:1996 with amendments to gather a deeper understanding of the requirement and the procedure. It appears the procedure is at odds with the requirement. Please allow me to explain. The requirement is to establish 75% of the field points to be within -0 dB to +6 dB. Exploring the uniformity by means of constant field strength invokes Clause 6.2 a, d, e, f, and h. I have trouble with clause e. Paraphrasing for simplicity, - take the data - find the mean in V/m - throw out the worst 25% - the remaining points shall lie within +/-3 dB - use the lowest of the remaining points as reference. The 4th step does not make sense to me. I can still maintain a -0, +6 dB spread without invoking a +/- 3 dB window about the median. As an illustration, suppose I have data that establishes a spread from -15 dB to +4 dB about the mean. My worst 4 points are -15, -14, -13, -12 dB. So these points are clearly further from the mean than +4 dB and are deleted. The remaining points are clustered between +1 and +4 dB. Step e says the remaining points shall remain within +/- 3 dB, so the point at +4 dB is considered non-compliant, even though it is only 3 dB away from the lowest point. Step f says to make the lowest point the reference for -0, +6 dB. This being the case, my non-compliant point, originally identified as +4 dB from the mean is now well within the -0, +6 dB range of the reference, but is considered non-compliant. I realize the standard allows up to 3% of points to fall between +6 and +10 dB, but that is not the issue. This point should not have been identified as non-compliant in the first place, but clause e requires it to be identified as non-compliant. Does anyone know the rationale to clause e? What am I missing? Are there any committee members out there who can shed some light on this? Kind regards, Don Umbdenstock TEPG -- Sensormatic 561 912 6440 --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Compact Chamber Calibration
Hi All, I read the standard EN 61000-4-3:1996 with amendments to gather a deeper understanding of the requirement and the procedure. It appears the procedure is at odds with the requirement. Please allow me to explain. The requirement is to establish 75% of the field points to be within -0 dB to +6 dB. Exploring the uniformity by means of constant field strength invokes Clause 6.2 a, d, e, f, and h. I have trouble with clause e. Paraphrasing for simplicity, - take the data - find the mean in V/m - throw out the worst 25% - the remaining points shall lie within +/-3 dB - use the lowest of the remaining points as reference. The 4th step does not make sense to me. I can still maintain a -0, +6 dB spread without invoking a +/- 3 dB window about the median. As an illustration, suppose I have data that establishes a spread from -15 dB to +4 dB about the mean. My worst 4 points are -15, -14, -13, -12 dB. So these points are clearly further from the mean than +4 dB and are deleted. The remaining points are clustered between +1 and +4 dB. Step e says the remaining points shall remain within +/- 3 dB, so the point at +4 dB is considered non-compliant, even though it is only 3 dB away from the lowest point. Step f says to make the lowest point the reference for -0, +6 dB. This being the case, my non-compliant point, originally identified as +4 dB from the mean is now well within the -0, +6 dB range of the reference, but is considered non-compliant. I realize the standard allows up to 3% of points to fall between +6 and +10 dB, but that is not the issue. This point should not have been identified as non-compliant in the first place, but clause e requires it to be identified as non-compliant. Does anyone know the rationale to clause e? What am I missing? Are there any committee members out there who can shed some light on this? Kind regards, Don Umbdenstock TEPG -- Sensormatic 561 912 6440 --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: Virus Alert
This hoax was passed around my area 6 months ago. The virus is a self-inflicted virus, i.e., doing what the email suggests damages a necessary part of your file manager program. See the link below for full details. -- From: Steve Grobe[SMTP:ste...@transition.com] Reply To: Steve Grobe Sent: Friday, May 10, 2002 11:47 AM To: 'Dan Teninty - DTEC Associates'; Emc-Pstc@Majordomo. Ieee. Org (E-mail) Subject: RE: Virus Alert This could very well be a hoax. http://www.sophos.com/virusinfo/hoaxes/sulfnbk.html -Original Message- From: Dan Teninty - DTEC Associates [mailto:dteni...@dtec-associates.com] Sent: Friday, May 10, 2002 9:52 AM To: dteni...@dtec-associates.com Subject: FW: Virus Alert Managing Partner DTEC Associates LLC (509) 443-0215 (509) 443-0181 fax http://www.dtec-associates.com Streamlining The Compliance Process While Advancing New Products To Market This email transmission is confidential and intended for the addressee only. It may contain privileged and confidential information. If you are not the person or organization to whom it is addressed, you must not copy, distribute, or take any action in reliance upon it. -Original Message- From: Brian Seppi [mailto:sbkathl...@qwest.net] Sent: Friday, May 10, 2002 2:05 AM To: Amy Robinson; Barry Chris Lines; Betty Brandle Subject: Virus Alert I was informed that I had received a virus from Dave Frank. According to his instructions, go to your start menu, find/search look for a file called sulfnbk.exe If you have the virus, you'll see a black icon next to the file. DELETE it (right click on it and go to delete) ...DO NOT OPEN IT!!! Then empty your recycle bin. It goes out to everyone in your e-mail address book. Our version of Virus Scan did not find it. I apologize for the inconvenience - Kathleen --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: Surge test on a loop
Hello Amund, My guess is that the 20 extra meters of cable allows coupling to be developed between the shield and the conductors contained within. If you do not isolate the one device from the rest of the devices in the loop, is it likely that you are shorting the surge signal to chassis (path of least resistance) without developing the signals on the internal conductors thereby not developing the prescribed signal to the intended device? The set-up figures in the surge standard provide guidance in this regard. Best regards, Don Umbdenstock Sensormatic Electronics Corp Tyco International -- From: am...@westin-emission.no[SMTP:am...@westin-emission.no] Reply To: am...@westin-emission.no Sent: Wednesday, March 20, 2002 4:58 AM To: emc-p...@majordomo.ieee.org Subject: Surge test on a loop Hi all, Assume a fire alarm detection system. 10 smoke detectors are connected in series on a loop and both ends of the loop is connected to the fire alarm panel. Shielded cable is used and the shield is connected through the whole loop. So, how do we carry out the surge test on the loop? The alarm panel and the detectors are all EUTs. As far as I understand IEC61000-4-5:1995 chapter 7.5, I will insert an extra 20 meter shielded cable between each detectors and then I will drive the surge pulse onto the shield in order to test one of the detectors. Then I move the extra 20m cable to the next detector and surge test it. If this is correct, why can't we just put the surge pulse onto the shielded loop and assume that the whole loop was tested at once? 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: davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: SDR in the US
Kim, I believe the Part you desire is 47 CFR 15.231 (Part 15, clause 231) ...the intentional radiator is restricted to the transmission of a control signal such as those used with alarm systems, door openers, remote openers, etc. The fundamental is allowed a level of 3,700 - 12,500 uV/m from 260-470 MHz. Other frequency ranges have other limits; some restrictions apply (sound like a lawyer?) ;-) If you would rather do 902-908 MHz, 15.247 applies for spread spectrum, or 15.249 for other applications. Spread spectrum allows more power but is complicated by the spread spectrum requirements. 15.249 is more restrictive in the power allowed. I have attached a link for your convenience. http://www.fcc.gov/oet/info/rules/ Best regards, Don Umbdenstock Sensormatic Electronics Corp Tyco International -- From: Kim Boll Jensen[SMTP:kimb...@post7.tele.dk] Reply To: Kim Boll Jensen Sent: Friday, March 15, 2002 7:35 AM To: treg; EMC-PSTC Subject: SDR in the US File: kimboll.vcf Hi all I have a Radio remote control for use in private homes I have understood that 433MHz SRD is not possible in the US in the same way as in EU. Some FCC notes points to 902 - 928 MHz for this kind of equipment. I'm trying to understand the FCC but I'm hindered by no possible download of relevant 47CFR code (http://www.access.gpo.gov/nara/cfr/waisidx_00/47cfr90_00.html doesn't seem to function at the moment) Is it correct that 902 -928 is allowed in part 15 without license if output is below 50mV/m at 3m, and if I need more power I will have to apply for a general license under part 90 ? Please help me ! Best regards, Kim Boll Jensen Bolls Raadgivning Denmark --- 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: davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Chamber Doors
We are purchasing an additional steel clad shield room for our compliance lab. The chambers all appear to carry a 5 year warranty but the doors carry a 1 year warranty. There must be a reason why the door has a much shorter warranty period than the rest of the chamber. We currently have 2 chambers. One is a used chamber from Universal Shielding that we have used for going on 7 years and the door works great, despite being moved 3 times while we have owned it. The other is a relatively new chamber built by Panashield that we have had for roughly 3 years. No problem with this door either. Both have a smooth engagement and can be easily operated with one hand on the handle. Our maintenance has been minimal, perhaps insufficient for prolonged trouble-free service. Can you share with us what experiences you have had with doors of your steel clad chambers? If you could share such things as chamber vendor, hinge adjustments, door maintenance recommended and performed, warranty claims and length of time without problems, that would help us understand the 1 year policy. Anyone have any interesting stories? Best regards, Don Umbdenstock 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: davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: Comparing EMI test results
We have also performed some experimentation with our compact semi-anechoic chamber (prescan) and OATS, both at 3 meters. Our experience correlates with Doug's. For devices as small as say a shoebox, our correlation is typically within 2 dB. For systems that are 1.5 meters and floor mounted with a few interconnecting cables, our correlation is typically within 4 dB. We have seen an occasional emissions in the chamber that did not show up on the site. As we use a bilog in the chamber and use bicon and log periodic on the site, we did not pursue the why. I would assume that it is related to the imperfect absorption of the chamber compared to the open space of the OATS. Another part that might make a difference in your measurements is the conditions at each site. Our chamber is a fairly constant 72 degrees, 50% humidity producing a constant NSA. The OATS, however, varies in its moisture content which we have learned contributes to the variation between chamber and OATS. When the site is dry, we get a down the middle NSA; when it is soaked, we get closer to the NSA limit and also a larger variation between the chamber and OATS as would be expected. We have not yet discovered why the moisture affects the NSA. On the other hand, the OATS is compliant and we have learned to deal with the degrees of variation, so at this point we live with it. Don Umbdenstock -- From: Doug McKean[SMTP:dmck...@auspex.com] Reply To: Doug McKean Sent: Monday, January 07, 2002 1:44 PM To: EMC-PSTC Discussion Group Subject: Re: Comparing EMI test results Not to rain on the parade, but be careful when comparing semi-anechoic chambers versus OATS that are of different distances, i.e. 3m vs. 10m. You may get not only widely different measurements even when compensating for the distances, but you may also obtain different frequencies. On two occasions, I've had frequencies show up rather prominently in the chamber prescan not to be seen to any significance at an OATS. In other words, to get a fairly reliable comparison between a chamber and a site, in my opinion, you'll first have to compare a 10m chamber with a 10m OATS. Then, work backwards to a 3m chamber. You will also have to develop a fudge factor for the size of the EUT. The size can effect results as well. You may get good correlation with a small tabletop EUT and terrible correlation to a much larger device. Possible reasons for this I'll leave to discussion. But suffice it to say, the closer the product is to a point source the better the correlation. The farther the product is from a point source, the worse the correlation. At least in my experience. Name the site with which you will be getting an official measurement as your standard, then work all the others in reference to it. The standard site will be the one which will have the final say. Sorta been there ... Done that ... etc ... Sorta gave up. - Doug McKean --- 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: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org 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.
RE: Non-compliant product put into EU marked
Is there a route for special temporary authorization or experimental license for a specific customer location? This may be on a spectrum authority (SA) by SA basis. Just do it! may be a fine logo for selling shoes, but does not work in legal arenas. Don Umbdenstock Sensormatic Electronics Tyco International -- From: Tania Grant[SMTP:taniagr...@msn.com] Reply To: Tania Grant Sent: Monday, December 17, 2001 1:33 PM To: am...@westin-emission.no; emc-p...@majordomo.ieee.org Subject: Re: Non-compliant product put into EU marked Is the manufacturer serious, or completely ignorant? If serious, I would disassociate from them as much as possible. If merely ignorant, and you have some sort of association with them, I would recommend that you educate them fully. Another thought, -- is this product slated for mass distribution, even for only a month, or is it going to another location or a particular customer for some special in-house use or application? What does this customer think? Are they aware, and do they agree to this? The Directives do have special provisions for certain special applications where non-compliant (or is it merely untested !) product can be shipped to Europe, but I believe that under those circumstances, the name of the manufacturer and product model name or designation has to be published broadly in the EU. I don't remember the details. If anyone can shed more light, that would be very nice. taniagr...@msn.com - Original Message - From: am...@westin-emission.no To: emc-p...@majordomo.ieee.org Sent: Sunday, December 16, 2001 2:06 PM Subject: Non-compliant product put into EU marked Hi all, You place a radio product into the EU marked with the following status: - Not been EMC, radio or safety tested (the previous model was tested and compliant, major modifications have later been implemented) - The product will only be in the marked for a time limiting period ( 1 month) - During the time limiting period it will be operating as in a normal condition - No CE mark on the product and no DoC I mean that you can't do this. You have to confirm that you fulfil the EMC, radio and safety requirements, DoC in place, even that the product just will be in the marked for 1 month and thereafter withdrawal. Any other comments from the list members ? 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: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org 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.
