| 摘要 |
PURPOSE:To use a magnetic recording medium under the optimum conditions at all times, by using a reader of the magnetic characteristics information and a controller of the recording current. CONSTITUTION:For a magnetic disk 4, the optimum recording current coefficient is recorded as the magnetic characteristic information at a part of the outermost circumference of an encoder. A magnetic head 7 functions as a magnetic sensor to read the magnetic characteristic information as well as a writing head to record the data to a magnetic disk 5. An amplifier 8 converts the signal that read the magnetic characteristic information into the pulse signal, and an F2F demodulator 9 separates the pulse signal to a clock as the data signal. The data signal and the clock are fed to a CPU10. The CPU10 applies the output of the digital signal proportional to the optimum recording current coefficient to a D/A converter 18 and then converts it into the analog signal. The power supply part of a digital recording circuit 12 is connected to a D/A converting part 11. Thus the recording current flowing to the head 7 is controlled automatically to the optimum value by the part 11. |
