Article View: sci.electronics
Article #8573(Telephone) Ring Generator
From: Kyler Laird
Date: Wed, 28 Nov 1990 16:07
Date: Wed, 28 Nov 1990 16:07
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1175 bytes
I had many requests for my ring generator schematic. Recently I saw a project similar to the one I built for EE in Modern Electronics. I'll outline our approach. get 12VDC switch it with an optoisolator connect output to secondary of a 120V-12V transformer connect primary of xfrmr to telephone pulse the optoisolator with a 555 at 20Hz use another 555 (or just a 556) to interupt the ring signal (rrring...rrring...) Like a dummy, I didn't use the transformer. Instead, I played around with a push-pull approach using about 48VDC per side. Didn't have the power I needed to ring mechanical ringers. I have hopes that the higher voltage will do it. I doubt the current I was providing did any good. --kyler
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arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!samsung!noose.ecn.purdue.edu!mentor.cc.purdue.edu!lairdkbShow Full Headers
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!samsung!noose.ecn.purdue.edu!mentor.cc.purdue.edu!lairdkb From: lairdkb@mentor.cc.purdue.edu (Kyler Laird) Newsgroups: sci.electronics Subject: (Telephone) Ring Generator Message-ID: <1902@mentor.cc.purdue.edu> Date: 28 Nov 90 16:07:12 GMT Reply-To: lairdkb@mentor.cc.purdue.edu (Kyler Laird) Distribution: usa Organization: Purdue University Lines: 22