Path: utzoo!attcan!uunet!pyrdc!netsys!vector!nobody
From: ll-xn!ames!hplabs!hpda!dclaar@vector.uucp (Doug Claar)
Newsgroups: comp.dcom.telecom
Subject: How to detect if phone is off-hook (and not in use)
Message-ID: <telecom-v08i0181m06@vector.UUCP>
Date: 16 Nov 88 18:43:35 GMT
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X-TELECOM-Digest: volume 8, issue 181, message 6

(I hope I wasn't supposed to send to telcom-request--it didn't say
in the header)

I am wondering if there is a device commercially available--cheap, or
a circuit floating around somewhere that will detect when a phone is
off-hook and not in use. The phone company sends those loud tones, but
you don't always hear them. (You see, we have small children, who
occasionally knock the phone off-hook...) This circuit would be different
from the line-in-use circuit which has been discussed here, in that I
don't care if the line is "in use," unless nobody is using it.

Thanks,
Doug Claar
HP Information Software Division
UUCP: mcvax!decvax!hplabs!hpda!dclaar -or- ucbvax!hpda!dclaar
ARPA: dclaar%hpda@hplabs.HP.COM