I was looking into a telephone ringer circuit and found the following post on another message board:
http://www.controlbooth.com/forums/sound-music-intercom/17026-building-my-own-live-doorbell-phone.html
(Scroll down to post #5.)
Unfortunately, the poster didn't supply his schematic or code, and hasn't been active on that board since July 2011.
But I noticed that it was by someone in New Zealand. Hmm, could it be a member here? I couldn't find anything in a search of the board.
http://www.controlbooth.com/forums/sound-music-intercom/17026-building-my-own-live-doorbell-phone.html
(Scroll down to post #5.)
Unfortunately, the poster didn't supply his schematic or code, and hasn't been active on that board since July 2011.
But I noticed that it was by someone in New Zealand. Hmm, could it be a member here? I couldn't find anything in a search of the board.