Build a Telephone Conversation Recorder Circuit Diagram
Build a Telephone Conversation Recorder Circuit Diagram . This Telephone Conversation Recorder Circuit Diagram enables automatic switching-on of the tape recorder when the handset is lifted. The tape recorder gets switched off when the handset is replaced. The signals are suitably attenuated to a level at which they can be recorded using the ‘MICIN’ socket of the tape recorder. Points X and Y in the circuit are connected to the telephone lines. Resistors R1 and R2 act as a voltage divider. The voltage appearing across R2 is fed to the ‘MIC-IN’ socket of the tape recorder. The values of R1 and R2 may be changed depending on the input impedance of the tape recorder’s ‘MIC-IN’ terminals. Capacitor C1 is used for blocking the flow of DC. The second part of the circuit controls relay RL1, which is used to switch on/off the tape recorder. Telephone Conversation Recorder Circuit Diagram A voltage of 48 volts appears across the telephone lines in on-hook condition. This volta...