Used to run into something similar when testing old telecom POTS lines years back. CISPR 24, if I recall correctly, has a set of criteria for determining a pass for immunity to demodulating the 1kHz.
With the POTS lines, the problem was finding a POTS test set that could give you a 1kHz tone dB level measurement that was immune itself. The test sets generally were not designed with immunity in mind. We later switched to a simple battery driven loop current CO simulator setup and software running on the EUT itself to measure any 1kHz tone and report the dB level. Minimizing the external test equipment during immunity testing is always desirable. Are you using the EUT itself to measure the demodulated level or an external device or just using your ears and the headphones? -- Dan Roman, N.C.E. IEEE Senior Member [email protected] [email protected] On Sep 5, 2018, 2:00 AM, at 2:00 AM, Amund Westin <[email protected]> wrote: >Wired headsets and microphones connected to a product, often acts as >receiver for induced RF fields. That means you quite often hear the >1kHz >modulation tone under the RF immunity tests. This is quite annoying for >the >user and above a certain level, not acceptable. > > > >To avoid such phenomena is quite a big task to conduct. But have anyone >of >you any experience how to determine if the headsets / microphones or >the >connected final product is the source to this problem? 3rd. party >headsets / >microphones have of course different RF immunity performance, and after >a >lot of testing, you might be able to find headsets / microphones that >are >does not pick up fields and the hearing audio noise level is >acceptable. > > > >I assume that the final product may have great level of immunity, but >as >long the headsets / microphones has poor immunity level, you will have >this >audio problem anyway. > >Has anyone been into this problem before? > > > >BR > >Amund > > > > > > > > > > > > > > >- >---------------------------------------------------------------- >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://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 <[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://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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
