http://www.ieee-pses.org/symposium http://www.emc2004.org/ -------------------------------------------------- Probably not enough info in the original post, at least for me. Injected signal source impedance would seem to be significant. If the source impedance is high, you could well use Mr. DeWitt's technique, with the source impedance determining the coupling capacitor value. Also if the RJ11 signal occupies a band well above 60 Hz, you could use inductors as the coupling device - never seen this done because usually the injected signal is at a higher, not lower frequency than the signal frequency. One last elegant technique would be a single primary winding on a magnetic core, with multiple identical secondaries, through which the RJ11 wires would be routed. Then they would all have the identical 60 Hz interference injected on all lines equally without disturbing the RJ11 signal. The impedance disturbance would be minimized if the primary were driven by a low impedance source which would short out the inductance the secondary presents when the primary is open-circuited.
From: "Brent DeWitt" <[email protected]> Reply-To: <[email protected]> List-Post: [email protected] Date: Thu, 8 Jul 2004 19:15:56 -0600 To: "Howard Ji \(howardji\)" <[email protected]>, <[email protected]> Subject: RE: help needed to inject/induce 100 V, 60 Hz common-mode noise http://www.ieee-pses.org/symposium http://www.emc2004.org/ -------------------------------------------------- You don't mention anything about the data requirements, so this may be silly, but why not use a standard "Y" capacitor like you would use for power supply filtering with the base of the "Y" connected to the hot side of the signal generator? Brent G DeWitt Loveland, CO http://home.ix.netcom.com/~bdewitt From: [email protected] mailto:[email protected]]On Behalf Of Howard Ji (howardji) Sent: Thursday, July 08, 2004 6:01 PM To: [email protected] Subject: help needed to inject/induce 100 V, 60 Hz common-mode noise http://www.ieee-pses.org/symposium http://www.emc2004.org/ -------------------------------------------------- Hi, I need to inject/induce a 60Hz common mode signal with a p-p voltage of around 100V onto a RJ11 cable. I have signal generator, amplifier and some coupling devices but none of my stuff works at 60 Hz. Any information would be appreciated. Thanks in advance. Howard ------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. IEEE PSES Main Website: http://www.ieee-pses.org/ To post a message send your e-mail to [email protected] Instructions for use of the list server: 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: Ron Pickard: [email protected] Dave Heald: [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. IEEE PSES Main Website: http://www.ieee-pses.org/ To post a message send your e-mail to [email protected] Instructions for use of the list server: 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: Ron Pickard: [email protected] Dave Heald: [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
