| 摘要 |
PURPOSE:To set recording current at an optimum point by so constituting the apparatus that signals are recorded with a recording system wherein a recording current adjusting circuit is recorded in a constant current recording state, the recorded signals are reproduced by inserting said circuit in the reproduction system and the reproduced outputs are made variable by adjusting this circuit. CONSTITUTION:When testing switches SW2-a, SW2-b and SW2-c are set in the state of the figure, and further recording switches SW1-a-SW1-f are changed over from the state of the figure to the recording states for testing, the oscillation signal of an oscillator 12 for testing is amplified 7 through the SW2-a, SW1-d, is level-adjusted 11, and is recorded and amplified 9. The amplified output is recorded with a recording-playback head 1. At this time, a level adjusting circuit 11 is beforehand set near the center of a variable range and a recording compensating circuit 10 is kept disconnected during recording. At the same time, a testing terminal is kept monitorted. After recording in this way, all the switches are changed over to the playback state. In the test playback state, the compnesating circuit 10 is connected to the amplifier 9. At the playback, the circuit 11 is vriably set so that the reproduced output voltage measured with the terminal 15 coincides with the monitored voltage. |
