Telephone line monitors

Posted on Feb 6, 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. 2. Some countries or states require you to notif

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

y anyone you are talking to that the conversation is being recorded. Most recoders do this with a beep-beep. Also, you may have to get permission from the phone company before you connect anything to their lines.

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