Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!zaphod.mps.ohio-state.edu!casbah.acns.nwu.edu!nucsrl!telecom-request From: floyd@ims.alaska.edu (Floyd Davidson) Newsgroups: comp.dcom.telecom Subject: Re: How do You Hook up a Phone For a Play? Message-ID: Date: 20 Feb 91 05:49:04 GMT Sender: news@casbah.acns.nwu.edu Organization: University of Alaska, Institute of Marine Science Lines: 55 Approved: Telecom@eecs.nwu.edu X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@eecs.nwu.edu X-Telecom-Digest: Volume 11, Issue 137, Message 2 of 6 Originator: telecom@delta.eecs.nwu.edu Roy Smith writes: >John_Richard_Bruni@cup.portal.com writes: >> I have on several occassions seen phones hooked up to AC to ring the >> bell for plays >Our Moderator replies: >> What you are suggesting is a *highly dangerous* practice ... > OK, I'll agree that it's a Bad Idea, and I'm not advocating >that you do it, but let's think about this for a minute. Just how >[Moderator's Note: An actual phone line not being used has closer to >forty volts DC on the line doesn't it? It goes up to ninety volts only >when ringing ... and only around ten volts DC when off hook ... I >think my figures are correct. But a straight 110-120 volts AC coming >into it for even a few seconds? Never! That is not really such a bad idea, *if* you do it right. *If* you do it wrong it is a *really* bad idea. Normal ringing voltage is about 100 volts at 20 Hz, and it is truely nasty stuff. Getting jerked around by 20 Hz current will teach some true respect. Don't confuse that with a relatively mild 60 Hz shock. (Either one can kill you.) But, the ring voltage is current limited. It is in series with a ballast lamp. Even a dead short will not blow a fuse. In an earlier post someone suggested a fuse and a 5k resister in series with the phone. It probably won't ring the phone. Rig up a lamp socket in series with the phone and a push button switch. Plug in a relatively small lamp, say a 15 watt job. If the phone rings loud enough, that's it, if not then use a larger lamp until it does. One word of caution: Have someone who understands electicity do this. The switch MUST be on the hot side of the wiring. If this is wired correctly there is no more danger from using 60 Hz current than from 20 Hz. Either way you end up with enough juice to knock your socks off if you touch it. And I'll admit to being semi scared to death of 60 Hz house current, but I'm also ten times as scared of 20 Hz ring current. It *HURTS*! Floyd L. Davidson | floyd@ims.alaska.edu | Alascom, Inc. pays me Salcha, AK 99714 | Univ. of Alaska | but not for opinions. [Moderator's Note: No problem! Everyone putting on an amateur play for their school, etc 'understands electricity' don't they? :) PAT]