HP 7942 Service Manual page 69

FROM
18
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S T- 5 0 6
INTERFACE
H2
H2P2
Theory of Operation
7942 and 7946
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DISC DRIVE ASSEMBLY A1 :
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L J1 RMFMI
ACTUATOR SERVO CONTROL
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18
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RMFM- nSmS
DATA
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UFN- POMER ON RESET SEEK SERYO'
14
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576 KHZ CLOCK . .
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SPINDLE SPEED CONTROL
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CLOCK
STOP MOTOA
ACTUATOR
~--~~-------~--~~~---------~~-----~
SENSORS-1311
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91.1 KHZ
LOCK
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AND INOEl
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576
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FILE=FSIEFB7D
1C
Figure 3-5. Disc Drive, Functional
Block Diagram, (Sheet 3 of 3)
3-39/3-40