[mod.telecom] Line In Use Circuit: How do I make one?

ewhac@lll-lcc.ARPA@well.UUCP (01/10/87)

[ Hello.  My name is Peabody.  I suppose you know yours.... ]

	Hold circuits are nice, but I'd like to build a little circuit that
turns an LED on or something on all other phone extensions when one of the
extensions is in use (thus letting someone in another part of the house know
the phone is in use).  This will go a long way to keeping my mother from
picking up the phone when I'm talking to another computer.

	Has anyone seen such a beast?  Pointers to such would be
appreciated.

	AtDhVaAnNkCsE.

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