| 摘要 |
Servoregulation system for drum motor and tape transport motor in a video recorder made of two separate control systems, that is, equipped with a separate system for drum motor speed and phase control which contains a phase decoder, analogue keys and operational amplifiers, and equipped with a separate system for tape transport motor speed and phase control, composed of a microprocessor, 8-bit digital-to-analogue converter and operational amplifiers, whereas output of each of the systems is connected with control input of a corresponding motor, which has its feedback output connected with a control system input, characterized in that in a single control system, the drum motor feedback output is connected to one of interrupt inputs (INT1) of the microprocessor (μC) by means of a signal line (DFG) and through the first forming unit (UF1), and an output of one of the microprocessor's ports (P1) is connected with a controlled input of a drum motor through a digital-to-analogue converter (C/A) by means of control signal line (DCON), whereas tape transport motor feedback output is connected, through the second and third forming units (UF2) and (UF3) as well as indirectly through an expander (EXP) to the second interrupt input (INT2) of the microprocessor (μC), and output of the second of the microprocessor's ports (P2) through a digital-to-analogue converter is connected with controlled tape transport motor input by means of a control signal line (CCON).<IMAGE>
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