Article View: sci.electronics
Article #21418Re: How can I restrict outgoing phone calls?
From: Henry Spencer
Date: Thu, 18 May 1989 04:25
Date: Thu, 18 May 1989 04:25
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In article <21001@genrad.UUCP> cah@genrad.UUCP (Chris A. Heitmann) writes: >...If you do what you say, disable the keypad, they >can still make calls anywhere they want with a hand held dialer (assuming >that you have tone service)... And if they're deft, they can make calls anywhere they want even if you *don't* have tone service, by rapidly pulsing the hookswitch (the switch that distinguishes between "on hook" and "off hook", often by having the receiver's weight rest on it when "on hook"). All a conventional phone dial does as it returns after you've turned it to a number is to open and close the circuit repeatedly. Phone exchanges are tolerant enough that you can do the same thing manually, at least on a standard Bell phone. (Might not work on electronic ones.) -- Subversion, n: a superset | Henry Spencer at U of Toronto Zoology of a subset. --J.J. Horning | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
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Newsgroups: sci.electronics Path: arc1-ca.pugleaf.net!utzoo!henry From: henry@utzoo.uucp (Henry Spencer) Subject: Re: How can I restrict outgoing phone calls? Message-ID: <1989May18.042535.9003@utzoo.uucp> Organization: U of Toronto Zoology References: <778@tetons.UUCP> <21001@genrad.UUCP> Date: Thu, 18 May 89 04:25:35 GMT