Hi Bill, I take exception when you say data taken at 3m will often show surprising difference if measured at 10m even if set up identically
My observations, with typical small objects not great big things, is that emissions are very close at both distances apples to apples.... What does change is that the mast height at which the emission maximizes changes.. Also, 10 metre testing MISSES emissions from EUTs at higher mast heights. IMHO it reaffirms my opinion that the current tests are regulatory, and not oriented towards problem mitigation. It's time we got back to just doing whats necessary to stop practically observed problems. Darn, that turned into a soapbox fast.... Happy holidays, Derek. Bill Stumpf wrote: > Grace, > Any good Calibrated Noise Emitter at the correct frequency range is a > good source for checking your OATS or chamber. There are "Round > Robin" programs offered by a couple groups that can anonymously show > results of your lab compared to other labs participating. When > testing actual products what must be remembered is that every EUT will > look different from one site to the next due to setup and test > distance, among other variables. Also, EUT's are generally > "distributed" RF sources and data taken at 3m will often show > surprising difference if measured at 10m even if set up identically. > > Bill > > ------------------------------------------------------------------------ > *From:* [email protected] [mailto:[email protected]] *On Behalf Of > *Grace Lin > *Sent:* Friday, November 20, 2009 6:54 AM > *To:* [email protected] > *Subject:* 3-meter Chamber Site Comparison > > Dear Members, > > I am asked to perform site comparison and would like to hear your > comments. > > Should I purchase a signal source? If yes, do you have any > reference? I do have a COM-POWER comb generator and don't know if it > is good enough for the purpose. > > Should I use an EUT for site comparison? > > Thank you. > > Best regards, > Grace Lin > > > > > > > - > ---------------------------------------------------------------- > 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] <mailto:[email protected]>> > > All emc-pstc postings are archived and searchable on the web at > http://www.ieeecommunities.org/emc-pstc > Graphics (in well-used formats), large files, etc. can be posted to > that URL. > > 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] <mailto:[email protected]>> > Mike Cantwell <[email protected] <mailto:[email protected]>> > > For policy questions, send mail to: > Jim Bacher <[email protected] <mailto:[email protected]>> > David Heald <[email protected] <mailto:[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] <mailto:[email protected]>> > > All emc-pstc postings are archived and searchable on the web at > http://www.ieeecommunities.org/emc-pstc > Graphics (in well-used formats), large files, etc. can be posted to > that URL. > > 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] <mailto:[email protected]>> > Mike Cantwell <[email protected] <mailto:[email protected]>> > > For policy questions, send mail to: > Jim Bacher <[email protected] <mailto:[email protected]>> > David Heald <[email protected] <mailto:[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.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. 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]>
