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From: floyd@wam.umd.edu (Jim Matthews)
Newsgroups: sci.electronics
Subject: Need phone line in-use indicator
Keywords: Elliptic Filter
Message-ID: <1991Jun12.232239.29424@wam.umd.edu>
Date: 12 Jun 91 23:22:39 GMT
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Organization: University of Maryland
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	Hi.  I'm not a normal subscriber to this newsgroup, so sorry if this
has been brought up before.  I have a modem and am sick of people picking up
phone extentions elsewhere in the house to make a call not knowing that I'm
on the line.  Is there a simple circuit I could build that would light an
L.E.D. or something when the phone line is in use?  Then I could put one of
these little lights on every extension to warn people that the line is already
in use so that they don't pick up the extension.
	Please e-mail replies, and I'll post a summary if there is interest.
	Thanx so much!						-Jim
-- 
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