Path: utzoo!attcan!uunet!pyrdc!netsys!vector!nobody
From: wheels@mks.UUCP (Gerry Wheeler)
Newsgroups: comp.dcom.telecom
Subject: sensitive relay wanted
Keywords: line pickup relay
Message-ID: 
Date: 23 Sep 88 16:00:23 GMT
Sender: chip@vector.UUCP
Organization: Mortice Kern Systems, Waterloo, Ont.
Lines: 23
Approved: telecom-request@vector.uucp (USENET Telecom Moderator)
X-TELECOM-Digest: volume 8, issue 146, message 4
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I'm looking for a relay to place in series with a telephone which will
open (or close) when the set is offhook.  The closest I've come is with
a 200 ohm 4.5 mA relay.  It didn't affect the phone operation too much,
but wouldn't quite pull in.  If I pressed the armature in, it would
latch.  Close, but no cigar.

Perhaps I should describe what I'm up to.  I want to share a phone line
between a fax machine and a phone or modem.  Only the fax will receive
incoming calls.  I want to put a relay coil in series with each device.
Its normally closed contacts will be in series with the *other* device.
Thus, when one is in use, the other is excluded.

So, what type of relay should I be looking for (impedance/current).  Is
such a thing commonly available? Will this scheme work? Does ringing
current cause any problems?

Our site doesn't receive this group, so direct email would be
appreciated.
--
     Gerry Wheeler                           Phone: (519)884-2251
Mortice Kern Systems Inc.               UUCP: uunet!watmath!mks!wheels
   35 King St. North                             BIX: join mks
Waterloo, Ontario  N2J 2W9                  CompuServe: 73260,1043