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From: mfontana@eniac.seas.upenn.edu (Mark A Fontana)
Newsgroups: sci.electronics
Subject: Need "line in" circuit for telephone
Message-ID: <44873@netnews.upenn.edu>
Date: 19 Jun 91 23:35:27 GMT
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Reply-To: mfontana@eniac.seas.upenn.edu (Mark A Fontana)
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Hello all,

    I'm working on a project that requires a direct audio connection to
the telephone line (to speak to the user, play music from tape, etc).
The level of the signal will be the standard "line out" level found
on most home audio equipment.
    Could someone describe a circuit to handle this connection?
I would like to ensure that the audio source is suitably protected, of course,
and a volume control is essential.

Thanks,

Mark Fontana
mfontana@eniac.seas.upenn.edu