Re: EMI sniffer goggles
I just jumped into the middle of this thread now - sounds really exciting. The liquid crystal idea sounds like a possibility.. My understanding of liquid crystals is that they do not take much of a field to effect but I do not know if it is down in the millivolt/M range that we all care about. I also think that there would have to be a tuning of the specific liquid crystal to the frequency based on physical size, Electrical characteristics and polarity of the crystal. Perhaps one would have different sheets for different frequency ranges or maybe one could mix different liquid crystals. Another issue is the detection of the effect itself. When the field interacts with the LC they would be alighned differently effecting the polarization of the light. If one used polarized light as a source then the sheet and then polarized glasses perhaps you could actually see an effected area as different intensities of light. Chris Wells cdwe...@stargate.net ..- Original Message - From: Wan Juang Foo f...@np.edu.sg To: EMC-PSTC Discussion Group emc-p...@majordomo.ieee.org Sent: Tuesday, August 07, 2001 6:28 PM Subject: Re: EMI sniffer goggles I suppose that can be achieve with some class of liquid crystals embedded in a polymer medium. The problem is that is the representation in the near field or just a plane (cross section). I will prefer a none intrusive gas or vapour that will 'glow' at different field intensity and colour, very much like a corona or aurora. :-) Now we can have a glass tank 'gas chamber' within an anechoic chamber to evaluate the field strengths in 3D. Then the argument will be that there will be different gasses for different frequent frequency ranges ;-) Just think about the possible effect on the environment. Dreams comes true when we want them to... Tim Foo, (or just call me 'Tim') E-mail: f...@np.edu.sg ECE, School of Engineering, http://www.np.edu.sg/ece/ Tel: + 65 460 6143 Ngee Ann Polytechnic, Fax: + 65 467 1730 535 Clementi Road, Singapore 599489 Doug McKean dmck...@corp.auspex.coTo: EMC-PSTC Discussion Group emc-p...@majordomo.ieee.org m cc: (bcc: Wan Juang Foo/ece/staff/npnet) Sent by: Subject: Re: EMI sniffer goggles owner-emc-pstc@majordom o.ieee.org 08/08/01 05:18 AM Please respond to Doug McKean Okay, here's what I'd like to have ... Translucent material which is color responsive to emi. Similar to the material on the side of batteries which responds to voltage levels. A pane of translucent material which can be put on the end of a stick much like a pane of glass or a pane of of it which could be stood from a floor support next to the product and show a pattern of emi strengths by color. Or, a thin sheet of it much like plastic wrap which can be placed on a part of a product (such as a surface or edge) which would also respond to field strength. snip --- 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: http://www.rcic.com/ click on Virtual Conference Hall, --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
Re: EMI sniffer goggles
Interesting discussion. I doubt such a thing, if it's ever made, would work at an OATS. More likely a troubleshooting tool for an anechoic chamber. There ambients are zilch and what you see is from your device. Little break from the usual topics, but refreshing. Thanks! - 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: http://www.rcic.com/ click on Virtual Conference Hall,
Re: EMI sniffer goggles
Um... This thread is getting more interesting. 1 millivolt per meter is about the size of it, at 3 m for the typical test failure. I suspect at 1 m or closer we will be measuring much more than 1 mV/m is (1000 microvolts/m or) 60 dBuV/m if the source is a high impedance source (most probably in the near field unless we are working in the ) but then we can never know for sure if it is High Z or Low Z. ;-) Some applied chemist could work hard on the idea of a glowing gas and that will make our lives very interesting. We will be measuring luminous intensity! probably with an optical instruments and some form of a camera in place of an antenna an a EMI receiver for electric field strength. :-) Tim Foo, (or just call me 'Tim') E-mail: f...@np.edu.sg ECE, School of Engineering, http://www.np.edu.sg/ece/ Tel: + 65 460 6143 Ngee Ann Polytechnic, Fax: + 65 467 1730 535 Clementi Road, Singapore 599489 Ken Javor ken.javor@emccompliancTo: Veit, Andy andy.v...@mts.com, EMC-PSTC Discussion Group e.com emc-p...@majordomo.ieee.org Sent by: cc: (bcc: Wan Juang Foo/ece/staff/npnet) owner-emc-pstc@majordomSubject: Re: EMI sniffer goggles o.ieee.org 08/08/01 10:59 PM Please respond to Ken Javor I hate to be a spoilsport but I believe we are also missing something which will react at millivolt or milliamp/meter field intensities. All these other sensors are reacting to relatively strong stimuli. -- From: Veit, Andy andy.v...@mts.com To: EMC-PSTC Discussion Group emc-p...@majordomo.ieee.org Subject: RE: EMI sniffer goggles Date: Wed, Aug 8, 2001, 7:23 AM Along the lines of EMI sensitive paper... There is such a thing for viewing magnetic fields, funnily enough. Its called Magnetic Viewing Paper and McMaster Carr has it for $14.22 for 27 square inches, p/n 5702K21. When the paper is laid over magnets, the paper shows the outline and shape of the field lines. Its handy for checking magnet assemblies for motors, and I have seen it used for this purpose. snip --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
RE: EMI sniffer goggles
The sheet material you linked is for DC magnetic fields and it is made by Magne-Rite® ( http://www.magnerite.com/ http://www.magnerite.com/ ). Since it uses Ni particle movement I doubt it will even get close to 30Mhz. One other question, how does one sniff with their eyes? -doug = Douglas E. Powell Regulatory Compliance Engineer Advanced Energy Industries, Inc. 1625 Sharp Point Dr. Ft. Collins, Co 80525 mailto:doug.pow...@aei.com mailto:doug.pow...@aei.com www.advanced-energy.com http://www.advanced-energy.com/ = -Original Message- From: Ehler, Kyle [mailto:keh...@lsil.com] Sent: Wednesday, August 08, 2001 9:19 AM To: 'Wan Juang Foo'; EMC-PSTC Discussion Group Subject: RE: EMI sniffer goggles Hi Tim, Welcome to the fray.. There is in existence a sheet material that exhibits these properties however, the flux sensitivity may not be sufficient for practical use with EMI work. I suspect it is for intense near field only. Here's a link: http://www.wondermagnet.com/dev/magnet34.html http://www.wondermagnet.com/dev/magnet34.html Has anybody experienced this material? -kyle -Original Message- From: Wan Juang Foo [ mailto:f...@np.edu.sg mailto:f...@np.edu.sg ] Sent: Tuesday, August 07, 2001 8:28 PM To: EMC-PSTC Discussion Group Subject: Re: EMI sniffer goggles I suppose that can be achieve with some class of liquid crystals embedded in a polymer medium. The problem is that is the representation in the near field or just a plane (cross section). I will prefer a none intrusive gas or vapour that will 'glow' at different field intensity and colour, very much like a corona or aurora. :-) Now we can have a glass tank 'gas chamber' within an anechoic chamber to evaluate the field strengths in 3D. Then the argument will be that there will be different gasses for different frequent frequency ranges ;-) Just think about the possible effect on the environment. Dreams comes true when we want them to... Tim Foo, (or just call me 'Tim') E-mail: f...@np.edu.sg ECE, School of Engineering, http://www.np.edu.sg/ece/ http://www.np.edu.sg/ece/ Tel: + 65 460 6143 Ngee Ann Polytechnic, Fax: + 65 467 1730 535 Clementi Road, Singapore 599489 --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
RE: EMI sniffer goggles
Hi Tim, Welcome to the fray.. There is in existence a sheet material that exhibits these properties however, the flux sensitivity may not be sufficient for practical use with EMI work. I suspect it is for intense near field only. Here's a link: http://www.wondermagnet.com/dev/magnet34.html Has anybody experienced this material? -kyle -Original Message- From: Wan Juang Foo [mailto:f...@np.edu.sg] Sent: Tuesday, August 07, 2001 8:28 PM To: EMC-PSTC Discussion Group Subject: Re: EMI sniffer goggles I suppose that can be achieve with some class of liquid crystals embedded in a polymer medium. The problem is that is the representation in the near field or just a plane (cross section). I will prefer a none intrusive gas or vapour that will 'glow' at different field intensity and colour, very much like a corona or aurora. :-) Now we can have a glass tank 'gas chamber' within an anechoic chamber to evaluate the field strengths in 3D. Then the argument will be that there will be different gasses for different frequent frequency ranges ;-) Just think about the possible effect on the environment. Dreams comes true when we want them to... Tim Foo, (or just call me 'Tim') E-mail: f...@np.edu.sg ECE, School of Engineering, http://www.np.edu.sg/ece/ Tel: + 65 460 6143 Ngee Ann Polytechnic, Fax: + 65 467 1730 535 Clementi Road, Singapore 599489
Re: EMI sniffer goggles
I hate to be a spoilsport but I believe we are also missing something which will react at millivolt or milliamp/meter field intensities. All these other sensors are reacting to relatively strong stimuli. -- From: Veit, Andy andy.v...@mts.com To: EMC-PSTC Discussion Group emc-p...@majordomo.ieee.org Subject: RE: EMI sniffer goggles Date: Wed, Aug 8, 2001, 7:23 AM Along the lines of EMI sensitive paper... There is such a thing for viewing magnetic fields, funnily enough. Its called Magnetic Viewing Paper and McMaster Carr has it for $14.22 for 27 square inches, p/n 5702K21. When the paper is laid over magnets, the paper shows the outline and shape of the field lines. Its handy for checking magnet assemblies for motors, and I have seen it used for this purpose. Another interesting paper is the new electronic paper being developed for electronic books. Embedded in the construction of the paper are millions of tiny spheres. Half of each sphere is black, half white. The spheres are aligned during the printing process with magnetic fields to show light or dark areas. There were photos and an article in the new issue of one of the free design rags that pile up on my desk. And don't forget that X-rays have been used to expose film for over 100 years. Sounds like we're just missing something sensitive to the portion of the spectrum between DC and X-rays! ;-) -Andy Andrew Veit Systems Design Engineer MTS Systems Corp Ph: 919.677.2507 Fax: 919.677.2480 1001 Sheldon Drive Cary, NC 27513 -Original Message- From: Doug McKean [mailto:dmck...@corp.auspex.com] Sent: Tuesday, August 07, 2001 5:18 PM To: EMC-PSTC Discussion Group Subject: Re: EMI sniffer goggles Okay, here's what I'd like to have ... Translucent material which is color responsive to emi. Similar to the material on the side of batteries which responds to voltage levels. A pane of translucent material which can be put on the end of a stick much like a pane of glass or a pane of of it which could be stood from a floor support next to the product and show a pattern of emi strengths by color. Or, a thin sheet of it much like plastic wrap which can be placed on a part of a product (such as a surface or edge) which would also respond to field strength. Or, I could rip off a sheet much like plastic wrap about a foot long and place over a pcb and instantly see the emi patterns produced by the board. Near or far field use. There'd be 2 versions of the material: one for electric fields which would respond with various shades of red and another for magnetic fields which would respond in various shades of blue. - 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: http://www.rcic.com/ click on Virtual Conference Hall, --- 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: http://www.rcic.com/ click on Virtual Conference Hall, --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
RE: EMI sniffer goggles
In a past job (10 years ago) another compliance engineer and myself were discussing how nice it would be to have EMI sunglasses while working on fixing a particularly noisy and troublesome piece of equipment. The idea was inspired by the X-ray glasses sold on the back cover of comic books. Might be a good ad to take out in the April issue of Compliance Engineering or Conformity magazines! Dan -Original Message- From: Wan Juang Foo [mailto:f...@np.edu.sg] Sent: Tuesday, August 07, 2001 9:28 PM To: EMC-PSTC Discussion Group Subject: Re: EMI sniffer goggles I suppose that can be achieve with some class of liquid crystals embedded in a polymer medium. The problem is that is the representation in the near field or just a plane (cross section). I will prefer a none intrusive gas or vapour that will 'glow' at different field intensity and colour, very much like a corona or aurora. :-) Now we can have a glass tank 'gas chamber' within an anechoic chamber to evaluate the field strengths in 3D. Then the argument will be that there will be different gasses for different frequent frequency ranges ;-) Just think about the possible effect on the environment. Dreams comes true when we want them to... Tim Foo, (or just call me 'Tim') E-mail: f...@np.edu.sg ECE, School of Engineering, http://www.np.edu.sg/ece/ Tel: + 65 460 6143 Ngee Ann Polytechnic, Fax: + 65 467 1730 535 Clementi Road, Singapore 599489 Doug McKean dmck...@corp.auspex.coTo: EMC-PSTC Discussion Group emc-p...@majordomo.ieee.org m cc: (bcc: Wan Juang Foo/ece/staff/npnet) Sent by: Subject: Re: EMI sniffer goggles owner-emc-pstc@majordom o.ieee.org 08/08/01 05:18 AM Please respond to Doug McKean Okay, here's what I'd like to have ... Translucent material which is color responsive to emi. Similar to the material on the side of batteries which responds to voltage levels. A pane of translucent material which can be put on the end of a stick much like a pane of glass or a pane of of it which could be stood from a floor support next to the product and show a pattern of emi strengths by color. Or, a thin sheet of it much like plastic wrap which can be placed on a part of a product (such as a surface or edge) which would also respond to field strength. snip --- 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: http://www.rcic.com/ click on Virtual Conference Hall, --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
RE: EMI sniffer goggles
Along the lines of EMI sensitive paper... There is such a thing for viewing magnetic fields, funnily enough. Its called Magnetic Viewing Paper and McMaster Carr has it for $14.22 for 27 square inches, p/n 5702K21. When the paper is laid over magnets, the paper shows the outline and shape of the field lines. Its handy for checking magnet assemblies for motors, and I have seen it used for this purpose. Another interesting paper is the new electronic paper being developed for electronic books. Embedded in the construction of the paper are millions of tiny spheres. Half of each sphere is black, half white. The spheres are aligned during the printing process with magnetic fields to show light or dark areas. There were photos and an article in the new issue of one of the free design rags that pile up on my desk. And don't forget that X-rays have been used to expose film for over 100 years. Sounds like we're just missing something sensitive to the portion of the spectrum between DC and X-rays! ;-) -Andy Andrew Veit Systems Design Engineer MTS Systems Corp Ph: 919.677.2507 Fax: 919.677.2480 1001 Sheldon Drive Cary, NC 27513 -Original Message- From: Doug McKean [mailto:dmck...@corp.auspex.com] Sent: Tuesday, August 07, 2001 5:18 PM To: EMC-PSTC Discussion Group Subject: Re: EMI sniffer goggles Okay, here's what I'd like to have ... Translucent material which is color responsive to emi. Similar to the material on the side of batteries which responds to voltage levels. A pane of translucent material which can be put on the end of a stick much like a pane of glass or a pane of of it which could be stood from a floor support next to the product and show a pattern of emi strengths by color. Or, a thin sheet of it much like plastic wrap which can be placed on a part of a product (such as a surface or edge) which would also respond to field strength. Or, I could rip off a sheet much like plastic wrap about a foot long and place over a pcb and instantly see the emi patterns produced by the board. Near or far field use. There'd be 2 versions of the material: one for electric fields which would respond with various shades of red and another for magnetic fields which would respond in various shades of blue. - 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: http://www.rcic.com/ click on Virtual Conference Hall, --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
Re: EMI sniffer goggles
I suppose that can be achieve with some class of liquid crystals embedded in a polymer medium. The problem is that is the representation in the near field or just a plane (cross section). I will prefer a none intrusive gas or vapour that will 'glow' at different field intensity and colour, very much like a corona or aurora. :-) Now we can have a glass tank 'gas chamber' within an anechoic chamber to evaluate the field strengths in 3D. Then the argument will be that there will be different gasses for different frequent frequency ranges ;-) Just think about the possible effect on the environment. Dreams comes true when we want them to... Tim Foo, (or just call me 'Tim') E-mail: f...@np.edu.sg ECE, School of Engineering, http://www.np.edu.sg/ece/ Tel: + 65 460 6143 Ngee Ann Polytechnic, Fax: + 65 467 1730 535 Clementi Road, Singapore 599489 Doug McKean dmck...@corp.auspex.coTo: EMC-PSTC Discussion Group emc-p...@majordomo.ieee.org m cc: (bcc: Wan Juang Foo/ece/staff/npnet) Sent by: Subject: Re: EMI sniffer goggles owner-emc-pstc@majordom o.ieee.org 08/08/01 05:18 AM Please respond to Doug McKean Okay, here's what I'd like to have ... Translucent material which is color responsive to emi. Similar to the material on the side of batteries which responds to voltage levels. A pane of translucent material which can be put on the end of a stick much like a pane of glass or a pane of of it which could be stood from a floor support next to the product and show a pattern of emi strengths by color. Or, a thin sheet of it much like plastic wrap which can be placed on a part of a product (such as a surface or edge) which would also respond to field strength. snip --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
Re: EMI sniffer goggles
Okay, here's what I'd like to have ... Translucent material which is color responsive to emi. Similar to the material on the side of batteries which responds to voltage levels. A pane of translucent material which can be put on the end of a stick much like a pane of glass or a pane of of it which could be stood from a floor support next to the product and show a pattern of emi strengths by color. Or, a thin sheet of it much like plastic wrap which can be placed on a part of a product (such as a surface or edge) which would also respond to field strength. Or, I could rip off a sheet much like plastic wrap about a foot long and place over a pcb and instantly see the emi patterns produced by the board. Near or far field use. There'd be 2 versions of the material: one for electric fields which would respond with various shades of red and another for magnetic fields which would respond in various shades of blue. - 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: http://www.rcic.com/ click on Virtual Conference Hall,
Re: EMI sniffer goggles
The only way you can get directionality is by looking at which dipoles/loops get the strongest signals. The dipoles or loops themselves have essentially no directivity. And the phase relationship won't work like a phased array radar, because those dipoles and delay lines are tuned for that microwave frequency, whereas the EMI goggles are electrically short. -- From: Chris Maxwell chris.maxw...@nettest.com To: Ehler, Kyle keh...@lsil.com, John Woodgate j...@jmwa.demon.co.uk, emc-p...@majordomo.ieee.org Subject: EMI sniffer goggles Date: Tue, Aug 7, 2001, 11:08 AM Hi all, I know this is all hypothetical, but... I think what's missing from the suggestions is a way to detect directivity of the emissions. So far what has been suggested is an array of detectors each linked to pixels. This would be very efficient at telling you which detectors have been hit by EMI. But, how would they be able to detect where the EMI was coming from? (i.e. provide a color coded view of the DUT) Maybe we could take a hint from the phased array radar guys and get a clue to directionality from the phase relationship. Of course, it would have to be reset at each frequency, but it's a start. Chris -Original Message- From: Ehler, Kyle [SMTP:keh...@lsil.com] Sent: Tuesday, August 07, 2001 8:37 AM To: 'John Woodgate'; emc-p...@majordomo.ieee.org Subject: RE: TV nostalgia True, but if the display range and bandwidth was tunable, and shown in 3-D chroma (similar to thermal imagers) rather than time domain -the emissions would make sense to the wearer. After all, even modern spectrum analyzers cannot show full bandwidth without compromising adjustments. -k -Original Message- From: John Woodgate [ mailto:j...@jmwa.demon.co.uk] Sent: Monday, August 06, 2001 12:29 PM To: emc-p...@majordomo.ieee.org Subject: Re: TV nostalgia 95fbd8b0830ed511b7720002a51363f1319...@exw-ks.ks.lsil.com, Ehler, Kyle keh...@lsil.com inimitably wrote: Doug has touched on what I think would be a great tool for the EMI hunter...but rather than a 'sniffer', a 'goggle' similar to what Geordi wears that facilitates the direct viewing of EM radiation. Ideally, the device would allow adjustable band 'viewing' of the radiation frequency, intensity, polarity and propagation pattern(s). Yes, it sounds much more attractive than a sniffer, which would produce BAD smells around some equipment. And it isn't technically unfeasible. The problem is the poor resolution, even a microwave frequencies, due to the wavelength of the emission. At 150 kHz, the wavelength is 2 km, so only very BIG things are visible. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk This message and its contents are not confidential, privileged or protected by law. Access is only authorised by the intended recipient - this means YOU! The contents may be disclosed to, or used by, anyone and stored or copied in any medium. If you are not the intended recipient, please advise the sender yesterday at the latest. --- 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: http://www.rcic.com/ click on Virtual Conference Hall, --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
