Hello Patrick, Deferring to others that have the history, as far as I can remember the impetus was good engineering practice.
On Wed, Jul 12, 2023 at 9:03 AM Patrick <[email protected]> wrote: > * This message originated outside of DISH and was sent by: > [email protected] <[email protected]> * > ------------------------------ > what year did measurement uncertainty become a required component of lab > accreditation? > > was there massive radio interference at homes and in offices that suddenly > ceased the year after? > > asking for a friend. > > On Tue, Jul 11, 2023, 10:28 Chas Grasso <[email protected]> wrote: > >> When the concept of measurement uncertainty came about, the company I >> worked for at the time decided that >> irrespective of the technical niceties of statistics if emission exceeded >> the spec but was within the stated MU, >> then that was still considered a FAIL. The difficulty came when the >> emission PASSED but was within the MU. >> The company decided that - even if the testhouse would not declare the >> pass, the product still shipped. >> >> In other words - life as usual. >> >> >> >> >> >> On Tue, Jul 11, 2023 at 9:13 AM Ken Javor <[email protected]> >> wrote: >> >>> * This message originated outside of DISH and was sent by: >>> [email protected] <[email protected]> * >>> ------------------------------ >>> >>> Not in the commercial sector, but people try this argument all the time >>> when failing a MIL-STD-461 limit by less than 3 dB, on account of the >>> measurement system integrity check has to be within that margin. >>> >>> >>> >>> They *never* express such concerns when they pass within 3 dB of the >>> limit, however. >>> >>> >>> >>> >>> >>> -- >>> >>> Ken Javor >>> >>> (256) 650-5261 >>> >>> >>> >>> *From: *Brian Kunde <[email protected]> >>> *Reply-To: *Brian Kunde <[email protected]> >>> *Date: *Tuesday, July 11, 2023 at 9:31 AM >>> *To: *<[email protected]> >>> *Subject: *Re: [PSES] FCC Part B questions >>> >>> >>> >>> If I may pile on late, keep in mind that measurement uncertainty is Plus >>> or Minus (±). Years ago when I was with a previous company, we had a >>> buy/sell piece of junk product that we were selling with our company's >>> brand/name on it. It was audited in Sweden as part of their >>> surveillance program and it failed by 2dB. The test lab said they could >>> not say it FAILED because 2dB was within their measurement uncertainty, so >>> we could continue to ship and sell this product in Sweden. >>> >>> >>> >>> Has anyone else ever experienced this? >>> >>> >>> >>> Thanks, >>> >>> The Other Brian >>> >>> >>> >>> >>> >>> On Sat, Jul 8, 2023 at 8:28 AM Brent DeWitt <[email protected]> >>> wrote: >>> >>> Hi Brian. It's not entirely clear which measurement range you are >>> asking about, but I'll assume conducted emissions in the range of 150 kHz >>> to 30 MHz. >>> >>> Short answer: You can skip QP and Avg detection if the peak detection >>> level is below the Avg detection limit. >>> >>> No margin is "required" to pass any emissions limit. Zero dB margin is >>> still passing. That said, measurement uncertainty in that range is >>> generally 3-4 dB, so having a passing margin greater than that gives you >>> some confidence that a re-test at another time and lab will still pass. >>> >>> Hope that helps. >>> >>> respectfully, >>> >>> Brent DeWitt >>> Milford, MA >>> >>> On 7/8/2023 12:38 AM, Brian Gregory wrote: >>> >>> >>> >>> Hi there, >>> >>> >>> >>> A question came up that I can't answer w/o a copy of Part 47. >>> >>> Does the FCC report require Quasi-Peak (QP) data, or just Avg and Peak. >>> When do peak readings trigger the need to report QP? I'm pretty sure Part >>> 15 has AVG and QP limits listed. >>> >>> >>> >>> Next was what sort of margin is expected in order to pass CE emissions >>> requirements (CISPR 16 or 32)? Memory serves that one wants 3dB of margin, >>> but memories can be imperfect! >>> >>> >>> >>> "Colorado" Brian >>> 720-450-4933 >>> >>> - >>> ---------------------------------------------------------------- >>> >>> 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 >>> <http://www.ieee-pses.org/emc-pstc.html> >>> >>> Website: http://www.ieee-pses.org/ >>> <http://www.ieee-pses.org/> >>> Instructions: http://www.ieee-pses.org/list.html (including how to >>> unsubscribe) >>> <http://www.ieee-pses.org/list.html> >>> List rules: http://www.ieee-pses.org/listrules.html >>> <http://www.ieee-pses.org/listrules.html> >>> >>> For help, send mail to the list administrators: >>> Mike Cantwell <[email protected]> >>> >>> For policy questions, send mail to: >>> Jim Bacher <[email protected]> >>> David Heald <[email protected]> >>> ------------------------------ >>> >>> To unsubscribe from the EMC-PSTC list, click the following link: >>> https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1 >>> <https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1> >>> >>> >>> >>> - >>> ---------------------------------------------------------------- >>> >>> 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 >>> <http://www.ieee-pses.org/emc-pstc.html> >>> >>> Website: http://www.ieee-pses.org/ >>> <http://www.ieee-pses.org/> >>> Instructions: http://www.ieee-pses.org/list.html (including how to >>> unsubscribe) >>> <http://www.ieee-pses.org/list.html> >>> List rules: http://www.ieee-pses.org/listrules.html >>> <http://www.ieee-pses.org/listrules.html> >>> >>> For help, send mail to the list administrators: >>> Mike Cantwell <[email protected]> >>> >>> For policy questions, send mail to: >>> Jim Bacher <[email protected]> >>> David Heald <[email protected]> >>> ------------------------------ >>> >>> To unsubscribe from the EMC-PSTC list, click the following link: >>> https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1 >>> <https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1> >>> >>> - >>> ---------------------------------------------------------------- >>> >>> 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 >>> <http://www.ieee-pses.org/emc-pstc.html> >>> >>> Website: http://www.ieee-pses.org/ >>> <http://www.ieee-pses.org/> >>> Instructions: http://www.ieee-pses.org/list.html (including how to >>> unsubscribe) >>> <http://www.ieee-pses.org/list.html> >>> List rules: http://www.ieee-pses.org/listrules.html >>> <http://www.ieee-pses.org/listrules.html> >>> >>> For help, send mail to the list administrators: >>> Mike Cantwell <[email protected]> >>> >>> For policy questions, send mail to: >>> Jim Bacher <[email protected]> >>> David Heald <[email protected]> >>> ------------------------------ >>> >>> To unsubscribe from the EMC-PSTC list, click the following link: >>> https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1 >>> <https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1> >>> - >>> ---------------------------------------------------------------- >>> >>> 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 >>> <http://www.ieee-pses.org/emc-pstc.html> >>> >>> Website: http://www.ieee-pses.org/ >>> <http://www.ieee-pses.org/> >>> Instructions: http://www.ieee-pses.org/list.html (including how to >>> unsubscribe) >>> <http://www.ieee-pses.org/list.html> >>> List rules: http://www.ieee-pses.org/listrules.html >>> <http://www.ieee-pses.org/listrules.html> >>> >>> For help, send mail to the list administrators: >>> Mike Cantwell <[email protected]> >>> >>> For policy questions, send mail to: >>> Jim Bacher <[email protected]> >>> David Heald <[email protected]> >>> ------------------------------ >>> >>> To unsubscribe from the EMC-PSTC list, click the following link: >>> https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1 >>> <https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1> >>> >> >> >> -- >> >> Charles Grasso >> >> Dish Technologies >> >> (c) 303-204-2974 >> >> (w) 303-706-5467 >> >> (h) 303-317-5530 >> >> (e ) [email protected] >> >> (e2) [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 >> <http://www.ieee-pses.org/emc-pstc.html> >> >> Website: http://www.ieee-pses.org/ >> <http://www.ieee-pses.org/> >> Instructions: http://www.ieee-pses.org/list.html (including how to >> unsubscribe) >> <http://www.ieee-pses.org/list.html> >> List rules: http://www.ieee-pses.org/listrules.html >> <http://www.ieee-pses.org/listrules.html> >> >> For help, send mail to the list administrators: >> Mike Cantwell <[email protected]> >> >> For policy questions, send mail to: >> Jim Bacher <[email protected]> >> David Heald <[email protected]> >> ------------------------------ >> >> To unsubscribe from the EMC-PSTC list, click the following link: >> https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1 >> <https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1> >> > - > ---------------------------------------------------------------- > > 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 > <http://www.ieee-pses.org/emc-pstc.html> > > Website: http://www.ieee-pses.org/ > <http://www.ieee-pses.org/> > Instructions: http://www.ieee-pses.org/list.html (including how to > unsubscribe) > <http://www.ieee-pses.org/list.html> > List rules: http://www.ieee-pses.org/listrules.html > <http://www.ieee-pses.org/listrules.html> > > For help, send mail to the list administrators: > Mike Cantwell <[email protected]> > > For policy questions, send mail to: > Jim Bacher <[email protected]> > David Heald <[email protected]> > ------------------------------ > > To unsubscribe from the EMC-PSTC list, click the following link: > https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1 > <https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1> > -- Charles Grasso Dish Technologies (c) 303-204-2974 (w) 303-706-5467 (h) 303-317-5530 (e ) [email protected] (e2) [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 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: Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]> _________________________________________________ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1
