Years ago, in Bay Area, CA [San Francisco's doctor's office located on 2nd floor, that's 1st floor to Brits] the high power AC lines that drooped by outside the second floor of a doctor's office were making 'wavy' patterns on all the monitors. It was a pronounced walking pattern moving up the screen, made you 'sea sick' after a while. You can imagine his complaining and trying to obtain mitigation from the utilities companies.
--- j...@jmwa.demon.co.uk wrote: From: John Woodgate <j...@jmwa.demon.co.uk> To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Audio Frequency Induction Loop Date: Sat, 25 Jan 2014 14:35:55 +0000 In message <003f01cf19cf$d908f000$8b1ad000$@cox.net>, dated Sat, 25 Jan 2014, Ed Price <edpr...@cox.net> writes: > On almost every field investigation I have done, the conventional >wisdom has been wrong. That is, whatever everybody at the site claims >the problem is, that?s almost never what it really turns out to be Indeed; I had a case where an induction-loop system exhibited interference that sounded just like fluorescent lamp interference, but it wasn't. The amplifier design had a problem; the circuit board was getting induced currents from the magnetic field of the mains transformer. -- OOO - Own Opinions Only. With best wishes. See www.jmwa.demon.co.uk Nondum ex silvis sumus John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>