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.
|R1||1||270K 1/4 W Resistor|
|R2||1||1.5K 1/4 W Resistor|
|R3||1||68K 1/4 W Resistor|
|R4||1||33K 1/4 W Resistor|
|C1||1||0.22uF 150 Volt Capacitor|
|Q1, Q2||2||2N4954 NPN Transistor|
|MISC||1||Wire, Plugs To Match Jacks On Recorder, Board, Phone Plug|
- The circuit can be placed anywhere on the phone line, even inside a phone.
- Some countries or states require you to notify 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.