Another example of transmission restriction is FCC 15.205. It states that only spurious emissions are allowed in certain bands.
Of course then it goes on to list all of the exceptions... Don Umbdenstock Manager Compliance Engineering Tyco Safety Products / Sensormatic 6600 Congress Avenue Boca Raton, FL 33487 USA 561.912.6440 [email protected] From: Ken Javor [mailto:[email protected]] Sent: Tuesday, July 12, 2005 1:59 PM To: [email protected] Subject: Re: Radiated emission measurement below 30MHz You are vastly OVERESTIMATING the load at 10 pF. A 41" rod over a ground plane is a 10 pF load. I find this thread interesting. I can buy an audio input device transmitting in the FM band for the purpose of playing an audio device through my automobile stereo system. Clearly this device was designed to intentionally transmit in the FM band, and further it must transmit with the same modulation and at the same center frequencies as stipulated by law for the FM band. So it is not as simple as saying you can't transmit in a broadcast band. There is the issue of control. If I am using the above described device, I will choose an FM channel not currently being broadcast on, and the power level is low enough it only reaches a few feet. > From: "Robert A. Macy" <[email protected]> > Date: Tue, 12 Jul 2005 08:52:23 -0700 > To: John Woodgate <[email protected]> > Cc: [email protected] > Subject: Re: Radiated emission measurement below 30MHz > > It radiated an ELECTROSTATIC field. We're talking voltage > field of 100V at 150KHz. A little 1 inch wire poked out > with 100 V on it. Current was the load of the parasitic > capacitance around 10pF. You can't even see that 10 m away > > Yet, not allowed, go figure. > > - Robert - > > On Tue, 12 Jul 2005 05:33:29 +0100 > John Woodgate <[email protected]> wrote: >> Robert A. Macy <[email protected]> wrote (in >> <[email protected]>) about 'Radiated emission >> measurement below 30MHz', on Mon, 11 Jul 2005: >>> Is this allowed? >>> >>> It was my understanding that one of my clients tried to >> get a *very* low power intentianal "radiator" [at these >> frequencies, radiator is a euphemism] through Europe and >> due to some application there, couldn't even start >> although the power could not even be measured within 10 >> meters. >>> Seriously, there was NOTHING at 10 m. They saw >> "intentional radiator" >>> 150KHz, and said NO. >>> >>> Did we use the wrong people? >> >> It's difficult to tell. Was 150 kHz the actual operating >> frequency or did it just emit (marginally) at that >> frequency? 150 kHz is just above the lower end of the LF >> broadcast band (lower end 148.5 kHz) and it could be >> argued that no intentional radiator can be accepted whose >> operating frequency is in a broadcast band. >> -- >> Regards, John Woodgate, OOO - Own Opinions Only. >> Deadlines are 90% of deadliness. >> http://www.jmwa.demon.co.uk Also see >> http://www.isce.org.uk >> >> > ---------------------------------------------------------------- >> This message is from the IEEE Product Safety Engineering >> Society >> emc-pstc discussion list. Website: >> http://www.ieee-pses.org/ >> >> To post a message to the list, send your e-mail to >> [email protected] >> >> Instructions: >> > http://listserv.ieee.org/listserv/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: >> >> Richard Nute: [email protected] >> Jim Bacher: [email protected] >> >> All emc-pstc postings are archived and searchable on the >> web at: >> >> http://www.ieeecommunities.org/emc-pstc > > ---------------------------------------------------------------- > This message is from the IEEE Product Safety Engineering Society > emc-pstc discussion list. Website: http://www.ieee-pses.org/ > > To post a message to the list, send your e-mail to [email protected] > > Instructions: http://listserv.ieee.org/listserv/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: > > Richard Nute: [email protected] > Jim Bacher: [email protected] > > All emc-pstc postings are archived and searchable on the web at: > > http://www.ieeecommunities.org/emc-pstc > This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/listserv/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: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/listserv/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: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
