| 摘要 |
PURPOSE:To set the optimum recording bias level with a simple operation, by flickering a display which displays the recording bias automatic set state in an accurate period and displaying the propriety after the end of automatic setting. CONSTITUTION:Through the operation of a recording bias automatic set button S0, a control signal is outputted to start an automatic set processing from a control circuit 12 to a recording bias level set circuit. During the automatic setting, an interruption signal frequency-divides the oscillating frequency of an oscillator 13 into a fraction at a frequency divider 14, interruption is given to this control circuit with this period, the automatic setting of the recording bias is interrupted to flicker a light emitting diode DL. An output terminal O1 of the control circuit is controlled so that it goes to high and low level in the said period. After the interrupting processing, the automatic setting is again made intermittently. After the end of the said automatic setting, the control circuit illuminates or distinguishes the light emitting diode depending on the success or failure of the recording bias setting. |
