Digital Equipment RK05 Series User manual

RK05 Exerciser
Maintenance Manual
digital equipmentcorporation magnard.massachusebts

1st Edition, April 1974
Copyright @ 1974 by Digital Equipment Corporation
The material in this manual is for informational
purposes and is subject to change without notice.
Digital Equipment Corporation assumes no respon-
sibility for any errors which may appear in this
manual.
Printed in
U.S.A.
The following are trademarks of Digital Equipment
Corporation, Maynard, Massachusetts:
DEC PDP
FLIP CHIP FOCAL
DIGITAL COMPUTER LAB

CONTENTS
Page
CHAPTER
1
CHAPTER 2
CHAPTER 3
CHAPTER 4
it' 4.1
4.2
4.2.1
4.2.1.1
4.2.1.2
4.2.1.3
4.2.1.4
4.2.1.5
4.2.2
4.2.2.1
4.2.2.2
,-, -"N 4.2.2.3
4.2.2.4
4.2.2.5
GENERAL INFORMATION
INTRODUCTION ...................................... 1-1
GENERAL DESCRIPTION
................................. 1-1
PHYSICAL DESCRIPTION
................................. 1-1
Exerciser Chassis
.................................... 1-1
Bus Terminator Module
................................ 1-1
Positioner Exerciser Module
.............................. 1 . 1
Writer Exerciser Module
................................ 1-1
Front Panel
...................................... 1-1
Unibus Cable Assembly
................................ 1-3
Power Cable
...................................... 1-3
SPECIFICATIONS
...................................... 1-3
Environmental
..................................... 1-3
Power Requirements
.................................. 1-3
Packaging
....................................... 1-3
UNPACKING.SET-UPAND ACCEPTANCETESTING
UNPACKING PROCEDURE ................................. 2-1
SET-UPPROCEDURE
.................................... 2-1
ACCEPTANCE TEST PROCEDURE
............................ 2-3
Writer Exerciser Module Test Procedure
........................ 2-3
Positioner Exerciser Module Test Procedure
...................... 2-6
OPERATION
SCOPE ............................................ 3-1
CONTROLS AND INDICATORS
.............................. 3-1
..................................
MODES OFOPERATION 3-3
.......................................
StepMode 3-3
Alternate Mode
.................................... 3-3
.....................................
Oscillate Mode 3-3
Random Mode
..................................... 3-4
UTILIZATION PROCEDURE
................................ 3-4
THEORY OF OPERATION
SCOPE ............................................ 4-1
FUNCTIONAL DESCRIPTION
............................... 4-1
Writer Exerciser
.................................... 4-1
Sector Decoder
.................................. 4-1
Write Control Logic
............................... 4-1
Write Clock
................................... 4-1
Clock and Data Output Multiplexer
....................... 4-1
Head Select Switch
................................ 4-1
Positioner Exerciser
.................................. 4-1
Strobe Oscillator
................................. 4-2
Address Counter Control Logic
......................... 4-2
Address Counter
................................. 4-2
Cylinder Address Source Select Logic
...................... 4-2
Fault Detect Logic
................................ 4-4
...
Ill

CONTENTS (Cont)
Page
CHAPTER 5
CHAPTER 6
APPENDIX A
APPENDIX
B
DETAILED LOGIC DESCRIPTION ............................. 44
Writer Exerciser
.................................... 4-4
Sector Decoder and Write Sector Switch
..................... 44
Write Control Logic
............................... 4-4
Write Clock
................................... 4-5
Clock and Data Output Multiplexer
....................... 4-5
Positioner Exerciser
.................................. 4-5
Strobe Oscillator
................................. 4-5
Address Counter Control Logic
......................... 4-8
Address Counter
................................. 4-10
...................... Cylinder Address Source Select Logic 4-10
Fault Detect Logic
................................ 4-11
FLOW DIAGRAM DESCRIPTION
............................. 4-11
MAINTENANCE
SCOPE
............................................ 5-1
MAINTENANCE PHILOSOPHY
............................... 5-1
TEST EQUIPMENT REQUIRED
.............................. 5-1
PREVENTIVE MAINTENANCE
.............................. 5-1
CORRECTIVE MAINTENANCE
.............................. 5-2
RK05 DISK DRIVE MAINTENANCE USING THERK05 EXERCISER
SCOPE
............................................ 6-1
ALIGNMENT. CHECKS. AND ADJUSTMENTS
...................... 6-1
...................................
Alignment Cartridges 6-1
.........................
RK05K-AC Alignment Cartridge 6-1
2315 CE Test Cartridge Shim Installation
.................... 6-2
Servo System Timing Checks and Adjustments
.................... 6-2
Dynamic Off-Line Checks and Adjustments
................... 64
..........................
Static Tests and Adjustments 6-9
ReadIWrite Data Separator (G180 Card) Adjustment
................. 6-10
........................
Read/Write Head Check and Alignment 6-10
.........................
RK05K-AC Alignment Cartridge 6-11
..................................
2315 CEPack 6-14
...........................
Index/Sector Timing Adjustment 6-16
.........................
RK05K-AC Alignment Cartridge 6-16
..................................
2315 CE Pack 6-18
.............................
Cartridge Receiver Alignment 6-19
1C SCHEMATICS
...........................
74424-LINE-TO-10-LINEDECODERS A-1
..................
7474 DUAL D-TYPE EDGE-TRIGGERED FLIP-FLOPS A-2
.........................
74123MONOSTABLE MULTIVIBRATOR A-3
74193 SYNCHRONOUS 4-BITUPIDOWN COUNTER (DUAL CLOCKWITH CLEAR)
. . A4
ENGINEERING DRAWING SET

Figure No .
ILLUSTRATIONS
Title
Page
RK05 Exerciser Components ................................ 1-2
Bus Terminator Module
................................... 1-2
Unibus Cable Assembly
................................... 1-3
Power Cable
......................................... 1-4
Exerciser to RK05 Disk Drive Connection Diagram
..................... 2-2
.............
RK05 Exerciser to Multiple RK05 Disk Drives Connection Diagram 2-3
Write Gate Data Waveform
.................................. 2-4
.........................
Writer Exerciser Clock and Data Waveforms 2-5
Write Data Waveforms
.................................... 2-7
How to Read a Vernier
.................................... 2-8
....................
RK05 Exerciser Front Panel Controls and Indicators 3-1
.........................
RK05 Exerciser Functional Block Diagram 4-3
Sector Decoder and Write Section Switch Diagram
..................... 4-4
Write Control Logic
..................................... 4-5
Write Clock
......................................... 4-6
Write Clock and Multiplexei Timing Diagram
........................ 4-6
Clock and Data Multiplexer Logic
.............................. 4-7
Strobe Oscillator
....................................... 4-7
Address Counter Control Logic
............................... 4-9
Address Counter Logic
.................................... 4-10
Cylinder Address Source Select Logic
............................ 4-11
Fault Detect Logic
...................................... 4-11
Writer Exerciser Flow Diagram
................................ 4-12
Positioner Exerciser Step Mode Flow Diagram
........................ 4-13
Positioner Exerciser Alternate Mode Flow Diagram
..................... 4-14
Positioner Exerciser Oscillate Mode Flow Diagram
...................... 4-15
Positioner Exerciser Random Mode Flow Diagram
...................... 4-16
Troubleshooting Flow Diagram
............................... 5-3
Spindle Runout (Negligible Runout)
............................. 6-1
Spindle Runout (Considerable Runout) ........................... 6-2
CE Test Cartridge Shim Installation
............................. 6-3
Sine AmplitudeIOffset and Velocity Offset Waveform
.................... 6-5
Cosine AmplitudeIOffset Waveform
............................. 6-6
Velocity Amplitude Waveform
................................ 6-7
Acceleration Waveform
................................... 6-7
Full Stroke Waveform
.................................... 6-8
Full Stroke Position Waveform
................................ 6-8
Outer Limit Waveform
.................................... 6-9
RK05-AC Alignment Cartridge Head Alignment Waveforms
................. 6-13
ReadIWrite Head Adjustments
................................ 6-15
2315CE Pack Head Alignment Waveforms
......................... 6-17
Index/Sector Waveform
................................... 6-19
Cartridge to Receiver Clearance
............................... 6-20
Cartidge Receiver Clearances
................................. 6-20
7442 Package and Logic Diagrams
.............................. A-1
DEC 74123 IC Illustrations
................................. A-3
DEC 74123 1C Output Pulse Width vs
. External Timing Capacitance ............ A-3
74193Logic Diagram
.................................... A-5

TABLES
Table No . Title Page
..............................
Exerciser Controls and Indicators 3-2
................................
Exerciser Operating Procedure 34
...........................
Data Bits Switchto Data Bit Correlation 3-8
..................................
Test Equipment.Required 5-1
..............................
Preventive Maintenance Schedule 5-2
.....................................
Servo System Checks 6-2
..................................
Servo System Adjustments 64

RK05 EXERCISER MAINTENANCE MANUAL

RK05-TA
RK05 - Exerciser

1.1 INTRODUCTION
This manual provides a complete description of the RK05
Exerciser, including physical, functional, logic level, and
flow diagram descriptions, specifications, and operation and
maintenance procedures.
1.2 GENERAL DESCRIPTION
The RK05 Exerciser is a portable unit used to exercise the
RK05 Disk Drive off-line. The unit generates all the control
signals necessary to exercise the disk drive linear positioner
circuitry and write circuitry; the processor and drive
controller are not needed.
The exerciser can be used to isolate most hard disk drive
faults and to verify proper operation once the fault has
been corrected.
NOTE
If reliability problems are encountered, the disk
drive should be checked out on-line, using
MAINDEC diagnostics.
The exerciser is completely contained in an aluminum
chassis and is powered by the RK05 Disk Drive power
supply. A special 4-wire power cable serves to route the
power supply outputs (t15 V,
- 15V, +5 V) to the
exerciser without interrupting power to the disk drive.
1.3 PHYSICAL DESCRIPTION
The exerciser (Figure 1-1)consists of five subassemblies and
two cable assemblies: exerciser chassis, front panel, bus
terminator module, test positioner module, test writer
module, bus cable assembly, and power cable.
1.3.1 Exerciser Chassis
The 9605720 chassis is a 6-1/10
in. high by 11-9/10 in.
wide by 3-6/10 in. deep metal box with a hinged front
panel.
CHAPTER 1
GENERAL INFORMATION
1.3.2 Bus Terminator Module
The M930 Bus Terminator module (Figure 1-2) is a dual
height module that is mounted in slot 2 of the connector
block and contains all the circuitry necessary to terminate
the Unibus.
1.3.3 Positioner Exerciser Module
The G503 Positioner Exerciser Module (Figure 1-1) is a
dual height module that is mounted in slot 3 of the
connector block. This module contains all the logic
necessary to exercise the disk drive linear positioner
circuitry. In response to front panel switch setting and disk
drive control signal inputs, the module generates control
signal and cylinder address outputs to the disk drive linear
positioner circuitry. The module also monitors the disk
drive fault lines and illuminates the front panel fault
indicators when a fault is detected. Refer to engineering
drawing D-CS-G503-0-1 for a complete physical layout and
parts identification.
1.3.4 Writer Exerciser Module
The G502 Writer Exerciser Module (Figure 1-1) is a dual
height module that is mounted in slot 4 of the connector
block. This module contains all the logic necessary to
exercise the disk drive write circuitry. In response to front
panel switch settings and disk drive control signal inputs,
the module generates control signals, clock, and data
outputs to the disk drive write circuitry. Refer to engi-
neering drawing D-CS-G502-0-1 for
a complete physical
layout and parts identification.
1.3.5 Front Panel
The 9605719 front panel (Figure 1-1) contains a 4-pin
female Mate-N-Lok input power connector and controls
and indicators necessary to exercise the disk drive. Refer to
engineering drawing D-UA-RK05-TA-0 for wiring data,
parts identification, and a complete physical layout.

FRONTPANEL
(9605719)
I
CONNECTOR BLOCK CHASSIS
(1205348 (9605720)
I 1
WRITER
EXERCISER
MODULE
NOTE:
UNIBUSAND POWER
CABLE NOTSHOWN
Figure 1-1 RK05 Exerciser Components
POSITIONER
EXERCISER
MODULE
(G503)
Figure 1-2 Bus Terminator Module
1-2

2.1 UNPACKINGPROCEDURE
To unpack the RK05 Exerciser, proceed as follows:
1. Unpack the unit from the shipping container
and inspect for damage. Damage claims should
be directed to the responsible shippers.
CHAPTER 2
UNPACKING, SET-UP
AND ACCEPTANCE TESTING
2. Check that the Unibus and power cables are
included with the exerciser.
2.2 SET-UPPROCEDURE
NOTE
The RK05 Exerciser may be
disk drive or as many as connected to one
four disk drives
simultaneously;however, the exerciser can only
exercise one drive at a time.
1.
To connect the RK05 Exerciser to one RK05
Disk Drive, the Unibus cable is installed as
follows (Figure 2-1):
a. Unplug the disk drive ac power cord.
b. Open the exerciser chassis and mount
either end of the Unibus cable assembly
(BC11A) into slot 1 of the connector
block.
c. Remove the disk drive prefilter and
ensure that the bus terminator module is
mounted in slot
7 of the disk drive
electronic module.
d.
Mount the other end of the Unibus cable
assembly into slot
8 of the disk drive
electronic module.
2. To connect the RK05 Exerciser to four RK05
Disk Drives, the Unibus cable is installed as
follows (Figure 2-2):
a. Remove all power from the RK05 Disk
Drives.
b. Disconnect the controller end of the
Unibus cable, which connects the RK05
Disk Drive to the controller module.
c. Open the exerciser chassis and mount the
disconnected Unibus cable into slot
1 of
the connector block.
3. To install the RK05 Exerciser power cable,
proceed as follows (Figure 2-1):
a. Remove the RK05 Disk Drive top cover.
b. Disconnect the PI Mate-N-Lokconnector
on the disk drive power supply.
c. Connect the 9-pin female connector (Jl)
of the exerciser power cable to
PI.
d. Connect the 9-pin male connector (P2) of
the exerciser power cable to Mate-N-Lok
connector Jl on the disk drive power
supply.
e. Connect the 4-pin male connector (PI) of
the exerciser power cable to the 4-pin
female connector (Jl) located on the
exerciser front panel.
(continued on page 2-3)

Figure 2-1 Exerciser to RK05 Disk Drive Connection Diagram

UNIBUS CABLES
RK05#1
EXERCISER
Figure 2-2 RK05 Exerciser to Multiple RK05 Disk Drives
Connection Diagram
f. Set the exerciser front panel Write
Constant toggle switch to the down
position.
CAUTION
The disk drive write circuitry must
not be exercised while an alignment
disk cartridge is installed in the disk
drive as serious damage to the
alignment tracks may result. The
alignment disk cartridge is
identified by a red access door
and/or a red label.
g. Apply power to the disk drive(s); observe
the disk drive blower motor comes on
immediately. After a short delay, the
door lock solenoid energizes
exerciser front panel POWER
cator illuminates.
h. Set the disk drive RUN/LOAD
LOAD and insert the DECpack.
i. Set the RUN/LOAD switch
observe the DECpack rotates.
and the
ON indi-
switch to
to RUN;
j. Set the exerciser front panel Drive
Selector knob to the ID (disk drive
identification number) of the disk drive
to be exercised.
2.3 ACCEPTANCE TEST PROCEDURE
The exerciser is shipped ready-to-use. If the unit is not
operating properly, refer to Chapter 5 (Maintenance) and
diagnose and correct the problem. Service should be
performed by qualified service personnel only.
To test the exerciser, obtain an RK05 Disk Drive that is
known to be operating properly, and set the exerciser up
for testing in accordance with the set-up procedure
described in Paragraph 2.2. After completing the set-up
procedure, perform the following test procedures.
NOTE
If faulty operation is detected at any point in
the following procedure, refer toChapter
5 and
correct the fault before proceeding to the next
step in the procedure.
2.3.1 Writer Exerciser Module Test Procedure
1.
Set the Write Sector knob to "ALL."
2. Set the Head Select-UPPER/LOWER toggle
switch to UPPER.
3. Depress the WRITE pushbutton repeatedly;
observe the disk drive front panel WT indicator
illuminates momentarily each time the WRITE
pushbutton is depressed.
4.
Set the Constant Write toggle switch to ON;
observe the disk drive front panel WT indicator
illuminates and does not extinguish until the
Constant Write toggle switch is set to the down
position.
NOTE
An oscilloscope (Tektronix
453 or equiv-
alent) is required to perform the follow-
ing steps.
5. Connect channel 1 scope probe to pin B08M2
on the RK05 Disk Drive logic block.

6. Toggle the exerciser Head Select toggle switch
up and down; observe a HIGH level signal
(t3V) when the toggle switch is set to LOWER
and a LOW level signal when the toggle switch
is set to UPPER.
7. Set the oscilloscope controls as follows:
Vertical
Mode
= ADD
Sensitivity
= 1V/div
Coupling
= dc
Sweep
A sweep time
= 5 ms/div
Trigger
= Normal
8. Connect the channel 1 probe to B08L2
(WRITE GATE
L) on the RK05 Disk Drive
logic block.
9. Connect the channel 2 probe to A02R2
(INDEX PULSE) on the RK05 Disk Drive logic
block.
10. Set exerciser Constant Write toggle switch to
ON.
11. Set the Write Sector knob to 0; observe the
display shown in Figure 2-3.
12. Set Write Sector knob to positions 1 through 9;
/
observe the index pulse moves in discrete steps.
NOTE
The index pulse is not visible on the
photograph shown in Figure
2-3 due to
photographic resolution limitations.
13. Set the oscilloscope controls as follows:
Vertical
Mode
= Chl
Sensitivity
= 1V/div
Coupling
= dc
Sweep
A sweep time
= 0.2 ps/div
Trigger
= Normal
14. Set all exerciser Data Bit toggle switches to the
0 position.
15. Connect channel 1 scope probe to A08F2 on
RK05 Disk Drive logic block and uncalibrate
the scope horizontal sweep to display four
negative-going pulses as shown in Figure 2-4a.
16. Set all four Data Bit toggle switches to the 1
position; observe eight negative-going pulses as
shown in Figure 2-4b.
INDEX PULSE APPEARS HERE
Figure 2-3 Write Gate Data Waveform

a. Clock Waveform
b. Clock and Data Waveform
Figure
2-4 Writer Exerciser Clock and Data Waveforms

17. Toggle each of the Data Bit toggle switches; 2.3.2 Positioner Exerciser Module Test Procedure
observe that each switch controls one of the
negative-going pulses.
1. Set the Function knob to STEP.
18. Set the oscilloscope controls as follows:
Vertical
Mode
= CHI
Sensitivity
= 0.5 V/div
Coupling
= dc
Sweep
A sweep time = 0.5 ps/div
trigger
= normal
19. Connect scope probe to TP3 on card GI80
(AB01 in RK05 Disk Drive).
20. Set exerciser RUN switch to the down position.
21. Set exerciser Constant Write and DC Erase
toggle switches to the down positions.
22. Set exerciser Write Sector knob toALL.
23. Set exerciser Head Select toggle switch to
UPPER.
24. Depress exerciser WRITE pushbutton; observe
data appears on display as shown in Figure
2-5a.
25. Set exerciser Head Select toggle switch to
LOWER and depress the WRITE pushbutton;
observe data appears as shown in Figure 2-5a.
26. Set the exerciser Head Select toggle switch to
UPPER.
27. Set the exerciser DC Erase toggle switch to ON
and depress the WRITE pushbutton; observe
data is erased completely as shown on Figure
2-5b.
28. Set the exerciser Head Select toggle switch to
LOWER; observe data is still present as shown
on Figure 2-5a.
29. Depress the exerciser WRITE pushbutton;
observe data is erased completely as shown on
Figure 2-5b.
30. Repeat steps 23 through 29 for sectors 0-9.
2. Set the FWD/REV switch to FWD.
3. Set the RTZ toggle switch to the down
position.
4.
Set the RUN switch to the up position; observe
the linear positioner moves to ever increasing
(inward) cylinder addresses.
5. Set the FWDIREV toggle switch to REV;
observe the linear positioner moves to ever
decreasing (outward) cylinder addresses.
6. Set all Cylinder Address toggle switches to 0.
7. Set the Function knob to ALT; observe the
linear positioner moves back and forth between
cylinder address 0 and ever decreasing cylinder
addresses.
8. Set the FWDIREV switch to FWD;observe the
linear positioner moves back and forth between
cylinder address 0 and ever increasing cylinder
address.
9. Set the RUN toggle switch to the down
position.
10. Set the Function knob to OSC.
11. Set the following Cylinder Address toggle
switches to the
1 position: 128, 64, 8, and 2
(cylinder address 202).
12. Momentarily set the RUN toggle switch to the
up position; observe the linear positioner moves
3
to cylinder address 202.
6
NOTE
Refer to Figure 2-6 for instructions on
reading the vernier.
13. Set Cylinder Address toggle switch
1, 4, 16,or
32 to the 1 position.
14. Set the RUN toggle switch to the up position;
observe the exerciser ADDR INV (address
invalid) indicator illuminates.

a. Write Data Waveform
b. Erase Data Waveform
Figure
2-5 Write Data Waveforms

15. Set the RUN toggle switch to the down
position and set all Cylinder Address toggle
switches to 0.
16. Set Cylinder Address toggle switch 128 to 1
and momentarily set the RUN toggle switch to
the up position; observe the linear positioner
moves to cylinder address 128.
17. Repeat steps 15 and
16 using each of the
remaining Cylinder Address toggle switches.
18. Set the RUN toggle switch to the up position
and set the Function knob to RAND; observe
the linear positioner moves to random cylinder
addresses.
19. Put the RK05 Disk Drive servo amp switch
(located to the left of the positioner assembly)
to the down position; observe the exerciser
SEEK INC (Seek Incomplete) indicator illumi-
nates. Return the servo amp switch to the up
position.
20. Set the RTZ toggle switch to the up position;
observe the linear positioner moves to cylinder
address 0 and stops.
* ^
5 0 200 50 100 50 00
~llllllll!llll!llllllllllllllll
PERFECTLY ALIGNED
TO READA VERNIER, proceed
As follows:
a. Determinethewhole number value of the nearest regular scale markingtothe right of Vernier scale triangle
(A).
b.
Add that value tothevalue of the vernier scale markingthat aligns perfectly with a regular scale marking.
c. Inthe illustrationshown above thevernier reading is: Regular Scale Marking
= 200
Vernier Marking
= - 2
Vernier Reading
= 202
Figure 2-6 How to Read a Vernier