Epson PX-8 Technical Manual page 152

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Fig. 3-6
3.1.5.2 Motor Revolution Speed Control Circuit
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IC5 2/64069
This circuit controls revolution of the capstan motor to ensure a cassette tape feed at a constant
speed. Tape must be read/written at a speed of 2.4
cm/s.
To secure this tape speed, the capstan
motor must revolve at 2,400 rpm.
Because no tape speed control is desired during fast forward feed or rewind, a function which can
enable or disable the tape speed control is also required. Fig. 3-7 is a block diagram of the internal
circuit of IC2.
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Single
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stabi-
lizer
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Fig. 3-7 IC2 Internal Circuit Block Diagram
3-6
Overshoot
suppression
circuit