[sci.electronics] Phone In Use Indicator

clear@cavebbs.gen.nz (Charlie Lear) (01/31/91)

This one pops up in comp.dcom.telecom every now and again, so I thought I'd
try sci.electronics for a change...

Apparently there is a simple circuit you can add to your phone to light an
LED when the line is in use. Radio Shack sell them. Schematics and how-to's
have been posted on the net a number of times.

Trouble is, they don't have RS stores in New Zealand and at the time the 
articles were posted, I didn't want an in-use indicator and skipped past 
them.

I have recently upgraded my BBS and Usenet systems to six lines total, plus
my voice line. Because they are pretty busy, I put a V32 modem on my voice
line so the 3B2 could dial out for newsfeeds without waiting for a free line.
Now I have the hassle of picking up the phone in the mornings while the news
is still flowing and getting an angry Microcom squawking in my ear.

Can someone please post schematics and a parts list for a cheap in-use
indicator that an electronics tyro can put together? Ideally I'd like it
small enough to slip inside the phones and have an LED indicator poking 
through a drilled hole in the case.
 
I promise to keep all postings so that I can send instant-response email
to the next person who asks... Mister Lippman, can you rescue me please?
8-)
-- 
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Charlie "The Bear" Lear | clear@cavebbs.gen.nz | Kawasaki Z750GT  DoD#0221
The Cave MegaBBS  +64 4 643429  V32 | PO Box 2009, Wellington, New Zealand
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