Telephone-tap


Posted on Aug 9, 2012

Amplify or record a telephone call with the simple circuit shown. The 8-0 secondary winding of a miniature transistor output transformer is connected in series with either of the telephone lines.


Telephone-tap
Click here to download the full size of the above Circuit.

The 1000-0 primary winding can feed either a cassette recorder or an audio amplifier.




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