RECORDING AMPLIFIER

PURPOSE:To reduce the time required for stabilizing the gain (rise time) by making 1st and 2nd amplifier circuits including their respective power supply circuits belong to the different systems whose temperature characteristics are both stable are independent of each other. CONSTITUTION:A signal inputted to an input terminal 4 is amplified by a voltage amplifier circuit 1, subjected to current amplification by a current amplifier circuit 2 and the result is outputted from an output terminal 5 as the recording current. The voltage amplifier circuit 1 having the power supply circuit 6 belongs to the system A, while the power supply circuit 7 belongs to the system B, the systems A, B are stable in the gain temperature characteristic but different from the temperature system. Thus, in case of operating the recording amplifier, a stable voltage is impressed simultaneously to the voltage amplifier circuit 1 and the current amplifier circuit 2. Thus, when the recording amplifier is started, the gain is made stable quickly.