HP 7925D Service Manual page 7

DC- W LED Indicator Troubleshooting
Flowchart 4-19
AGC LED Indicator Troubleshooting
Flowchart 4-20
CB LED Indicator Troubleshooting Flowchart 4-21
T LED Indicator Troubleshooting Flowchart 4-22
Door Unlock Solenoid Troubleshooting
Flowchart 4-23
DOOR UNLOCKED Indicator Troubleshooting
Flowchart 4-25
Unit Select Indicator Troubleshooting
Flowchart .. , 4-27
READ ONLY Indicator Troubleshooting
Flowchart 4-28
DRIVE READY Indicator Troubleshooting
Flowchart 4-29
RUN/STOP Switch Troubleshooting Flowchart .. 4-30
Spindle Rotation Troubleshooting Flowchart 4-31
Head Positioning Troubleshooting Flowchart 4-34
Emergency Return (CRB) Troubleshooting
Flowchart 4-37
Power Panel Assembly, Wiring Diagram 4-38
Mainframe Assembly, Wiring Diagram , 4-39
I/O Control System, Functional Diagram 4-41
Spindle Rotation System, Functional Diagram 4-43
Head Positioning System, Functional Diagram 4-45
Sector Sensing System, Functional Diagram 4-47
Read/Write System, Functional Diagram 4-49
Fault Detection System, Functional Diagram .4-51
Pack Detector Assembly 5-6
Using the Head Installation Tool , 5-8
Head Positioning 5-9
Use of Head Cam Alignment Tool , 5-12
Head Cam Tool Alignment 5-13
Spindle Screw Locations 5-15
Blower Motor Starting Capacitor 5-17
HP 7925D Disc Drive, Exploded View 6-5
Mainframe Assembly, Exploded View 6-9
Front Frame Assembly, Exploded View 6-10
Pack Chamber Assembly, Exploded View 6-13
Spindle Assembly, Exploded View 6-14
Power Supply Assembly, Exploded View 6-17
Actuator Assembly, Exploded View 6-19
Air Distribution Assembly, Exploded View 6-21
Operator Panel and Lower Card Cage
Assembly, Exploded View 6-23
Power Panel Assembly, Exploded View 6-25
Disc Pack, Exploded View 6-27
Termination Assembly, Exploded View 6-29
Title Page
Addressing Structure of an HP 7925 Disc Drive 1-1
Sector Clock and Index Generation 1-2
Logical vs. Physical Sectors 1-3
Surface Mode vs. Cylinder Mode 1-3
Sector Format 1-4
HP 7925 Disc Drive, Simplified Block Diagram 1-5
Disc Drive Interface 1-6
Tag Bus Timing 1-9
Phase Selection Timing , . " 1-14
Servo and Data Track Assignments 1-17
Air Circulation and Filtration System 1-30
Types of Contaminants and Critical Elements 1-31
Special Service Tools 2-3
DSU Test Module, Controls and Indicators " .2-5
Head Alignment Meter Calibrations 2-6
Measuring Absolute Filter Air Pressure 2-9
Pack Lock Lubrication Tool 2-10
Examples of Head Contamination 2-11
Prepared Head Cleaning Tool 2-12
Connector Assembly 3-1
Use of Head Cam Alignment Tool , 3-3
Head Cam Tool Alignment 3-4
DSU Installed 3-5
Data Head Alignment Locations , 3-7
Thermometer 3-7
Use of Circumferential Timing
Tolerance Label 3-8
Interpretation of Circumferential Timing
Data Graph 3-10
Data Graph Example 1 3-11
Data Graph Example 2 3-12
Data Graph Example 3 , .. 3-13
Data Graph Example 4 3-14
Data Graph Example 5 3-15
Data Graph Example 6 , 3-16
Data Graph Example 7 3-17
Track Follower Alignment 3-18
Actuator Crash Stop Clearance 3-20
Power-Up Troubleshooting Flowchart .. , , .. 4-10
Blower Troubleshooting Flowchart 4-11
DRIVE FAULT Indicator Troubleshooting
Flowchart 4-12
IL LED Indicator Troubleshooting Flowchart 4-13
W-AR LED Indicator Troubleshooting
Flowchart 4-15
R- W LED Indicator Troubleshooting
Flowchart 4-16
W-AC LED Indicator Troubleshooting
Flowchart '.' 4-17
MH LED Indicator Troubleshooting Flowchart 4-18
Title
ILLUSTRATIONS
I
Page
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