Telephone line monitor circuit


Posted on Feb 5, 2014

This nifty little circuit lets you record your phone conversations automatically. The device connects to the phone line, your tape recorder`s microphone input, and the recorder`s remote control jack. It senses the voltage in the phone line and begins recording when the line drops to 5 volts or less..


Telephone line monitor circuit
Click here to download the full size of the above Circuit.




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