Suggestions for PC MB and PS?
Hi all, I've determined that the Motherboard I have, is very noisy. Does anyone have a suggestions for a supplier that makes quiet Motherboards. Looking for a bog standard 1GHz clock board. Also, after testing several power supplies with a network analyser, I've determined that they have almost no filtering above about 50 MHz. What noise is on the low voltage side appears on the power cord... Anyone suggestions of a power supply manufacturer that makes one that does? Replies may be best off the list please, since I'm looking for Names. Thanks, Derek N. Walton Owner L F Research EMC Design and Test Facility Poplar Grove, Illinois, USA www.lfresearch.com
RF device certification in Brazil
I have a question for this august body concerning RF device regulations in Brazil. All my queries to the Brazilian authorities have gone unanswered for weeks now and I am harassed daily by our marketing group who are anxious to sell in Brazil. The company has a new product that contains a 1.8Ghz GSM data link - used with equipment we produce. The unit operates as a Mobile Cellular Device as far as Cell Phone Providers are concerned. The user simply establishes a GSM cell phone account with a local cellular provider. The RF unit is an OEM module that has both US/Canada and EU-RTTE RF device certifications. The product meets Class B emissions. The unit is battery powered. Max power output is 1watt. QUESTIONS: 1. Are the current certifications adequate, or are additional certifications specific to Brazil required for the RF module. ??? 2. Are operating licenses required for this type of device (it works just like a cell phone) ??? 3. Are special government forms required for importation operations of this product ??? Thank you very much for any assistance anyone can provide. Best Regards, Michael Taylor PE, NCE Ch. EMC Compliance Engineer Hach - Environmental Water Quality Division, Danaher Corp. Colorado, USA
Freebies
If anyone is interested in any freebies, please see me. I have the following available today. 1 LASER Printer 3 Dot Matrix Printers 1 Microwave Oven 1 X-Y Plotter (a-b size paper) with pens 1 Scanner (has a problem) If anyone has a need for any of these items, come see me. Courtland 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
Oops
Please disregard my previous email. I used the wrong address. The items are for people at my company. Courtland 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
Zone 2 Hazard classification
Hi Chris With reference to my previous email on zone 2 I do have an Explosion Protection manual; it describes hazardous area zones and protection methods. If you require a free copy in pdf please email me, the file size is about 2 meg regards John Osborne Technical Sales, PA PEPPERL + FUCHS 77 RIPPONDEN ROAD OLDHAM LANCASHIRE OL1 4EL Direct 0870 745 4865 Tel: +44 (0) 161 633 6431 Fax: +44 (0) 161 624 6537 Visit: www.gb.pepperl-fuchs.com ATEX CERTIFIED AND IEC 61508 (S.I.L) For all your Hazardous Area requirements Absolute Encoders to SIL Rated Isolators to Zener Barriers From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: 10 July 2003 19:27 To: EMC-PSTC Internet Forum Subject: Zone 2 Hazard classification Hi everyone, I hope that all of you are having a fun and safe summer. I know that this subject has been brought up before, but I can't find the searchable archives. If someone has the url, could you please email it to me, thanks. Anyway, we've had a customer ask about Zone 2 hazard classification of one of our products. They also mentioned a Class 1, Division 2. Can anyone fathom a guess at the following: 1. What standard do these classifications come from? 2. What kind of environment (in laymen's terms) are being referred to? Obviously, our product hasn't been evaluated to this standard. I'm just trying to get an idea of what kind of testing would be involved. adTHANKSvance Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | 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
Re: Need cheap hotel close to EMC show
Hi Charles, That's a tall order (request). My recommendations, look for hotels in Tewksbury (about 30 miles North and a bit West of Boston). There'e a plethora of hotels, suites,etc. and not a lot of business in those surroundings these days. It's accessible by I-93 and between Lowell and Andover. Another clutch of hotels can be found in and around Woburn near junction of I-95 and State RT 3. Another place to look is in Marlborough MA, near Junction of I-495 and State RT 20 where you will find close to half a dozen hotels. This is also 25-30 miles outside (West) of Boston. Best regards, Good Luck, Art Michael -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- |http://www.safetylink.com | || | The Safety Link is the most comprehensive collection | |of product safety and standards links on the WEB| || | Int'l Product Safety News | |(It's our 15th Anniversary 1988-2003 | | P.O.Box 1561 - WWW | |Middletown CT 06457-8061 U.S.A. | | Phone: (860) 344-1651 Fax: (860) 346-9066 | | email: i...@safetylink.com| -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- On Thu, 10 Jul 2003, Grasso, Charles wrote: any one have recommendations?? Best Regards Charles Grasso Senior Compliance Engineer Echostar Communications Corp. Tel: 303-706-5467 Fax: 303-799-6222 Cell: 303-204-2974 Email: charles.gra...@echostar.com; mailto:charles.gra...@echostar.com; Email Alternate: chasgra...@ieee.org mailto:chasgra...@ieee.org 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
FW: Field Solver Questions
Field solver experts: I received very few responses on-line and private. I guess this is due to lightning effect that upset some servers out there recently. Some experts may've been on summer vacation ... Here is another question from a different angle. Is/was there any effort to map any field solver algorithm to application-specific silicon? If so, what's the experience? If none, what are the pros and cons of such implementation? Thanks in advance, Sainath Date: Wed, 9 Jul 2003 11:50:05 -0800 From: Sainath Nimmagadda giga...@dacafe.com Reply-To: Sainath Nimmagadda giga...@dacafe.com To: si-l...@freelists.org, emc-p...@ieee.org Cc: giga...@dacafe.com Subject: Field Solver Questions Field solver experts: I have some generic questions. Consider the well-known finite element method(FEM) solver and assume full-wave solution and almost perfect boundary, unless mentioned otherwise. 1) Are there any benchmarks on the speed of these solvers compared to other kinds of solvers in time-domain or frequency-domain? 2) If a raw, non-optimized solver does it in T time, what is the likely max. speed improvement using conceptual or computational optimization? An educated guess will help for a start. 3) Suppose a solver is designed to solve for only three E(or H)components, instead of all six field components. What is the likely max. speed improvement? Again, an educated guess will help for a start. 4) Would you consider the solver in 3) a full-wave solver? If yes, under what conditions? If no, please give reasons. 5) If you were to design the solver in 3), what kind of conceptual pitfalls, if any, would you look for and try to avoid? Thanks in advance, Sainath _ _ 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
RES: RF device certification in Brazil
Dear Michael, since your product is a GSM cell phone, you need to follow the ANATEL (Brazilian telecommunication agency) requirements. Take a look at the pages 40, 41 and 42 of the document at http://www.anatel.gov.br/Tools/frame.as ?link=/certificacao/requisitoscategoriai.pdf (unfortunately all the documentation are in Portuguese). You will need to perform the homologation here in Brazil. First, you need to contract an OCD (chose one from the address http://www.anatel.gov.br/index.asp?link=/certificacao/ocd.htm?Cod=1576) they will care of the process with the ANATEL. Second, a laboratory will test your product according to requirements. Since your product complies with those requirements, it will receive a homologation number and each unit shall carry an ANATEL label. It is all you need to put a telecommunication device here in Brazilian market. Regards Sérgio L. Rocha Loures IC SC QP Q - Supply Chain Quality and Processes - Quality Assurance SIEMENS (Tel: +55 41 341-5898 ÊFax: +55 41 341-5058 *sergioro...@siemens.com.br Minha opinião e não necessariamente a do meu empregador. De: Michael Taylor [mailto:mtay...@hach.com] Enviada em: sexta-feira, 11 de julho de 2003 11:19 Para: emc-p...@majordomo.ieee.org Assunto: RF device certification in Brazil I have a question for this august body concerning RF device regulations in Brazil. All my queries to the Brazilian authorities have gone unanswered for weeks now and I am harassed daily by our marketing group who are anxious to sell in Brazil. The company has a new product that contains a 1.8Ghz GSM data link - used with equipment we produce. The unit operates as a Mobile Cellular Device as far as Cell Phone Providers are concerned. The user simply establishes a GSM cell phone account with a local cellular provider. The RF unit is an OEM module that has both US/Canada and EU-RTTE RF device certifications. The product meets Class B emissions. The unit is battery powered. Max power output is 1watt. QUESTIONS: 1. Are the current certifications adequate, or are additional certifications specific to Brazil required for the RF module. ??? 2. Are operating licenses required for this type of device (it works just like a cell phone) ??? 3. Are special government forms required for importation operations of this product ??? Thank you very much for any assistance anyone can provide. Best Regards, Michael Taylor PE, NCE Ch. EMC Compliance Engineer Hach - Environmental Water Quality Division, Danaher Corp. Colorado, USA
RE: cable maximization - do you or don't you??
Ken, if your attachment is of general value to everyone on the list, you can always put the attachment on the following site: http://www.ieeecommunities.org/emc-pstc That way everyone will have access to it. Jim 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: cable maximization - do you or don't you??
Chas, I solved that issue working on the presentation to the RMCEMC chapter meeting I never attended. I am sending the derivation to you as an attachment, off-list. Ken From: Charles Grasso cgrassospri...@earthlink.net Date: Mon, 7 Jul 2003 20:58:32 -0700 To: Ken Javor ken.ja...@emccompliance.com, Emc-Pstc emc-p...@ieee.org, charles.gra...@echostar.com Subject: RE: cable maximization - do you or don't you?? Hi Ken, Ahh the emissions analogy to the immunity tests? Hey - why not? After all there are plenty of conditions that arise NOT as an EUT problem but rather the artifical test environment that we use - i.e the OATS. We could then properly use a CALC without worrying about the cable radiation per se. Otts equation (derived from Banalis) is pretty accurate to half a wave length - the trick is what do you do after that? (Actually we have developed a correction factor here at Echostar..stay tuned..) -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Ken Javor Sent: Monday, July 07, 2003 8:29 AM To: Charles Grasso; Emc-Pstc; charles.gra...@echostar.com Subject: Re: cable maximization - do you or don't you?? An excellent opportunity to ask a question of list members, especially those involved in standards writing. Why not calculate the cable conducted emission that would result in radiated spec level compliance, and levy a cable conducted emission requirement? Then OATS testing would not require cable manipulation, and any out of spec conditions would result from test sample enclosure emissions. From: Charles Grasso cgrassospri...@earthlink.net Reply-To: Charles Grasso cgrassospri...@earthlink.net Date: Sun, 6 Jul 2003 13:53:40 -0700 To: Emc-Pstc emc-p...@ieee.org, charles.gra...@echostar.com Subject: cable maximization - do you or don't you?? Hi all, I have recently run into an issue with an OEM supplier. The product that we are looking at fails emissions after cable maximization. In an informal study, I discovered that quite a few labs don't seem to perform cable maximization on a routine basis. ANSIC63 is quite clear on this - the cables need to be maximized. Is cable maximization a thing of the past - to be written out - and test labs are maximizing throughput rather than cables OR is is something I should continue to insist on?? Comments will be gratefully accepted. Charles Grasso EchoStar Communicationa --- 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 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: cable maximization - do you or don't you??
Sorry for the delay in replying. It is clearly true that a given length of wire oriented in a particular direction could result in minimal radiation pick-up at some remote victim antenna. But in the same spirit of maximizing cable radiation during test, it is maxima for which we search. The exact same situation arises in reverse with the relationship between requirement 61000-4-3 and 61000-4-6. If one were to measure the pick-up on an EUT-connected cable during 61000-4-3, what would be observed would be significant variation in current/potential as a function of frequency (and indeed as a function of position on the cable itself at any single frequency at which the cable is electrically long). But the 61000-4-6 limit represents the maximum of what can be picked up; there is no (futile) attempt to reproduce the precise pick-up at some point or points on the cable at each frequency. If a conducted emission cable bundle requirement were to be levied, it would be based on the same considerations. Note an important caveat, electrical length. 61000-4-6 tailors the start frequency of the test according to electrical length, recognizing that short cables are inefficient radiators. The same could and should be applied to a cable-bundle emission requirement. From: John Woodgate j...@jmwa.demon.co.uk Reply-To: John Woodgate j...@jmwa.demon.co.uk Date: Tue, 8 Jul 2003 03:53:33 +0100 To: emc-p...@majordomo.ieee.org Subject: Re: cable maximization - do you or don't you?? I read in !emc-pstc that Ken Javor ken.ja...@emccompliance.com wrote (in bb2f7186.2be2%ken.ja...@emccompliance.com) about 'cable maximization - do you or don't you??' on Mon, 7 Jul 2003: I don't think it is at all complicated, at least in principle. Maybe a devil will emerge out of some details I am missing... It's a point worth discussing. I don't see how an end-driven wire can radiate more efficiently than a tuned half-wave dipole. That model can be used to convert from field intensity at X meters to peak current on the cable. Agreed that it can't be more efficient, but it can be less efficient to a nearly unlimited extent, so making that assumption can be very pessimistic indeed. For the case of multiple cables one could make various assumptions about the additive effect of emissions at X meters: A worst case assumption is that the same spectrum could appear on each cable and add in phase at the measurement point. This would require subtracting from the previously determined single cable current limit the factor: 20*log (number of cables). I think this is unreasonable, that the summing would be of random phase and the factor to be subtracted from the single cable current limit ought to be 10*log (number of cables). Agreed, as a first approximation. I am not trying to say that this approach is precisely correct and should be implemented as is. I do think it would be interesting to make some cable measurements using an absorbing clamp and compare to the corresponding OATS profile and draw some conclusions. Yes, I think that is justified, now that you have raised the subject. Unfortunately, many such proposals are never investigated because no-one has the time, even if the costs can be handled. I think we all look forward to your report of the first results. (;-) -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! --- 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.
Re: apertures
On Thu, 10 Jul 2003 12:58:49 -0600, drcuthb...@micron.com wrote: I have a question on apertures. You may recall the formula that is frequently given for signal attenuation through a small aperture in a large conductive sheet. It is 20LOG(I/2L), where I is the wavelength and L is the slot length. For example, if x is 1/2-wavelength then the attenuation is 0 dB. But I'm not 100% sure what the attenuation is referenced to. If they are referencing it to the E-field that would be present at the aperture location if the sheet were not there to the E-field across the length of the aperture then that makes sense. It seems that we now have a 1/2 wavelength aperture radiating only the signal energy that it has intercepted. Let's say it is referenced to the E-field that would be present with no sheet. Now to say that the E-field a large distance away from the 1/2 wavelength aperture has not been attenuated by the aperture is wrong, although this is implied by the formula. Only a fraction of the energy contained in the total incident wave has made it through the aperture. The aperture now acts as a dipole radiating this fraction of the total incident wave. So is the attenuation given by this formula to be referenced to the power that would be intercepted by a dipole? I'm not experienced in radiation issues, so I might be off-base. I remember this subject being discussed in Henry Ott's book, Noise Reduction Techniques in Electronic Systems. On page 182, he starts talking about shielding with magnetic metals, and about apertures specifically on page 187. It looks like the subject concerns magnetic currents induced in the metal radiating at the point of discontinuity (the slot). Is this the same situation as measuring shielding effectiveness with two antennas? 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
Thanks to all who responded
on the EMC show hotel Q. This is quite a problem.. Best Regards Charles Grasso Senior Compliance Engineer Echostar Communications Corp. Tel: 303-706-5467 Fax: 303-799-6222 Cell: 303-204-2974 Email: charles.gra...@echostar.com; mailto:charles.gra...@echostar.com; Email Alternate: chasgra...@ieee.org
