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 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://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 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://www.rcic.com/ click on "Virtual Conference Hall,"
