This is the place for any magazine-related discussions that don't fit in any of the column discussion boards below.
5 posts • Page 1 of 1
I am trying to find a message waiting indicator (MWI) circuit that I can connect to a phone line and have an LED glow or flash to indicate that there is a message on the telephone companies voice mail system. I (believe I) need to detect the stuttered dial tone that the phone company uses to indicate a message is waiting. I have seen this function on several phone units, but as yet have been unable to find a circuit or even functional description. An internet search results in all sorts of phones for sale with the function. I eventually would like to build a small box that plugs into my wall jack (rj45 - 4 individual lines) and display an LED for each line. Any pointers would be greatly appreciated.<p>Thanx
found a little bit more info - I am looking to implement a visual message waiting indicator (vmwi) prefereably with the ability to detect either the FSK signal or the stutter dial tone.<p>Any links to circuits or chip specs appreciated.
Thanks philba - tried Discover Circuits - no luck yet. I have found spec sheets for "Zarlink MT88E39" and "MXCOM CMX673" whose application noted indicate a 2 chip scenario - one chip handling the FSK the other chip takes the line off-hook and "listens" for the stutter tone, then goed back on-hook. I guess my original thought bias was going to be some sort of simple detector circuit. I wonder if anyone might have ideas on working with any of these chips - maybe with a microcontroller.
Users browsing this forum: Google [Bot] and 29 guests