John, FCC (ANSI C63.4 / C63.10) specifies a 60 cm shielded loop antenna for measuring radiated emissions from 9 kHz to 30 MHz (magnetic field, Rod antennas to measure electric field are not allowed).
The limit is written at 300 meters up to 490 kHz and 30 Meters from 490 kHz to 30 MHz. However, since you tend to be in the magnetic field of the earth we make the measurement at some near field distance of 10 or 3 meters using 40 dB/decade extrapolation factor. Larry -----Original Message----- From: John Woodgate [mailto:[email protected]] Sent: Friday, July 06, 2012 3:21 PM To: [email protected] Subject: Re: FCC maximum frequency measurement In message <[email protected]>, dated Fri, 6 Jul 2012, Bill Owsley <[email protected]> writes: >That's what bit me, an included radio. TCB wanted data from 32 kHz to >12 GHz. Easier than debating. How could you measure radiated emissions at 32 kHz, or in fact any frequency below about 10 MHz? -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk Instead of saying that the government is doing too little, too late or too much, too early, say they've got is exactly right, thus throwing them into total confusion. 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 <[email protected]> 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://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]> - ---------------------------------------------------------------- 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 <[email protected]> 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://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
