Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!lll-lcc!mordor!styx!ames!ucbcad!ucbvax!USC-ECL.ARPA!BEC.SHAPIN From: BEC.SHAPIN@USC-ECL.ARPA (Ted Shapin) Newsgroups: mod.telecom Subject: Looking for a line in use circuit Message-ID: <8612220415.AA02214@ucbvax.Berkeley.EDU> Date: Mon, 15-Dec-86 19:00:16 EST Article-I.D.: ucbvax.8612220415.AA02214 Posted: Mon Dec 15 19:00:16 1986 Date-Received: Mon, 22-Dec-86 03:04:59 EST Sender: daemon@ucbvax.BERKELEY.EDU Organization: The ARPA Internet Lines: 7 Approved: telecom@xx.lcs.mit.edu I would like to build a LED driver that will light when a line is in use. I guess I could use a CMOS inverter and drive it from the line. Does anyone have a circuit? Ted. [DAK sells this circuit as "Drew's Brainstorm" for ~$10. A 9-volt battery eliminator is recommended by yours truly. -Elmo]