Simple Telephone Recorder

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 1.5K 1/4 W Resistor R3 68K 1/4 W Resistor R4 33K 1/4 W Resistor C1 0.22uF 150 Volt Capacitor Q1, Q2 2N4954 NPN Transistor D1 1N645 Diode MISC Wire, Plugs To Match Jacks On Recorder, Board, Phone Plug.

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Telephone Recorder Switch by FET
This circuit will allow you to record both sides of your telephone conversations for future reference. For commercial orders placed over the phone such a recording device is invaluable. Read more original source:http://electronics-diy.com/electronic_schematic.php?id=575
Digital Voice Recorder-Playback UM5100
This Circuit is based on the UM5100 which can record speech into a digital memory and then play it back. The device is designed to be used directly with static RAM's up to 256K bits, or with EPROM 's or ROM's for playback only. High quality voice reproduction is possible and note that it is ...
Telephone Record Control
This circuit will allow you to connect any tape recorder that has a mic and remote input to a phone line and automatically record both sides of a conversation when ever the phone is in use. You will need to take a couple of voltage readings before connecting the circuit. First determine ...
Parallel Phone Tap Circuit Diagram
In a recent article, I discussed the difference between parallel and series telephone taps. In this article, I present a very simple and reliable parallel phone tap circuit useful for recording telephone conversations onto a tape recorder. When installing a telephone tap, its advisable no ...
Extension Phone Line Switcher by SCR 2N5061
Having multiple extension telephones at home is very convenient. You can make or receive phone calls practically anywhere in the house. This circuit disables other telephones connected to the phone line whenever a telephone (either the master or any extension phone) is in use. The circuit is ...