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From: pozar@well.UUCP (Tim Pozar)
Newsgroups: mod.telecom
Subject: Re: Connecting a phone line to a stereo
Message-ID: <8611270640.AA06603@ucbvax.Berkeley.EDU>
Date: Wed, 26-Nov-86 20:50:56 EST
Article-I.D.: ucbvax.8611270640.AA06603
Posted: Wed Nov 26 20:50:56 1986
Date-Received: Thu, 27-Nov-86 06:47:38 EST
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The ARPA Internet
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Approved: telecom@xx.lcs.mit.edu

>Can anyone give me a circuit for connecting a phone line to broadcast
>over a stereo system?  

    The circiut can be made very easliy out of two .1uf disk caps, and a 
10k to 600 ohm tranformer.  WARNING!  This circuit is not FCC accepted.  
   Ahem, now that I said that...  Just hook it up to the red and green wires
on the block.  The caps are to block DC to the transformer and prevent the 
Telco equipment from seeing a "off-hook" status.  In order to keep the line 
up, you should put a 1k resistor across the red and green wires.  You could 
even put a switch in series to act like a switch hook.

          .1uf
  Green __| |____    _________\  To consumer level/impeadence 
          | |    )||(         /         audio source
Telco       600  )||(  10K
          .1uf   )||(
    Red __| |____)||(_________\
          | |              |  /
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