Newsgroups: sci.electronics
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Device to determine caller's phone number
Message-ID: <1989Oct24.155040.28805@utzoo.uucp>
Organization: U of Toronto Zoology
References: <1989Oct23.204225.13207@alberta.uucp>
Date: Tue, 24 Oct 89 15:50:40 GMT

In article <1989Oct23.204225.13207@alberta.uucp> firat@alberta.uucp (Firat Uludamar) writes:
>Is there a device that could be attached to a phone to figure out what 
>number an incoming call originated from? ...

Sigh... this one comes up regularly.  (Anyone for a sci.electronics
frequently-asked-questions list?)  This CANNOT BE DONE without cooperation
from your phone company.  The phone exchange normally does not send any
indication of the calling number to your line, and there is no way for
a gadget on your line to ask for it.  Some phone companies in some areas
are semi-experimentally offering such a service, at extra cost.  Call your
phone company to find out whether it is available and at what price.
-- 
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry henry@zoo.toronto.edu