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From: bill@videovax.tv.Tek.com (William K. McFadden)
Newsgroups: sci.electronics
Subject: Re: Remote Beepers info needed
Message-ID: <5487@videovax.tv.Tek.com>
Date: 21 Jul 89 19:56:03 GMT
References: <20592@cup.portal.com>
Reply-To: bill@videovax.tv.tek.com.UUCP (William K. McFadden)
Distribution: usa
Organization: Tektronix TV Measurement Systems, Beaverton OR
Lines: 27

In article <20592@cup.portal.com> Peter_Warren_Lee@cup.portal.com writes:
>What I'd like to do is set up a
>computer to automatically answer a phone and if it hears a remote beeper
>(like those telephone answering machine beepers),perform some preset
>actions. The things I need to know are:
>1. Would it be possible to use an existing answering machine to do the job.

Sounds reasonable.

>2. What frequencies do those beepers operate at (just a general idea).

Not sure, but they're easy to imitate.  Security can be a problem.

>3. Has anyone already tried it?

I haven't personally, but I have heard of people hooking up touch-tone decoder
chips and having the computer respond to a "secret code."  This would reduce
or eliminate the security problem because the code can be as many digits as
needed.  Two other advantages: no beeper required, multiple codes for multiple
actions.  Two disadvantages: rotary phones (requiring a handheld touch-tone
"beeper"), forgetting the code.  Radio Shack has a touch-tone decoder chip that
would probably work.
-- 
Bill McFadden    Tektronix, Inc.  P.O. Box 500  MS 58-639  Beaverton, OR  97077
UUCP: bill@videovax.Tek.com,  {hplabs,uw-beaver,decvax}!tektronix!videovax!bill
GTE: (503) 627-6920         "The biggest difference between developing a missle
component and a toy is the 'cost constraint.'" -- John Anderson, Engineer, TI