IBM 5280 Technical Newsletter page 2

HOW TO USE THIS MANUAL. • • • • • • • • • • • • • • • • • • • ix
SAFETY . . . . . .
• • • • • • • • • • • • • • • • • • • X
MAINTENANCE
BASE MACHINE LOCATIONS
001 Front View. . . . . . . . .
011 Rear View . .
With Covers . .
Without Covers
COVERS
031 Removal and Replacement.
Data Station. . . . . . . . . .
Keyboard . . . . . . . . . . .
OPERATOR CONTROLS
· .. 1
· .2
.2
· .3
..4
· .. 4
· .. 6
071 Control Panel Removal and Replacement. . . . . . . . .7
073 Power Switch Removal and Replacement. . . . . . . . .8
075 Keylock Switch Removal and Replacement . . . . . .8
077 Screen Controls Removal and Replacement . . . . . 10
079 Drive-In-Use Indicator Removal and Replacement. . 11
KEYBOARD
10t Locations • . . . . . . . . . . . . . . . . . . . . . .
111 Break Code Service Check . . • . . .
113 Keyboard Layout and Scan Codes. . .
66-Key Keyboard (Data Entry) . . . . .
67-Key Keyboard (Data Entry) . . . . .
69-Key Keyboard (Data Entry) . . . .
83-Key Keyboard (Typewriter) . . . .
85-Key Keyboard (Typewriter) . . . .
115 Keyboard Cleaning . . . . . . . . . .
121 Key Module Removal and Replacement •.
123 Spacebar Removal and Replacement . • . .
125 Flyplate Replacement . . . . . . . . . . . . . .
127 Pad Printed Circuit..soard Removal and Replacement.
DISPLAY ASSEMBLY
. 12
.13
.14
.14
.14
• 15
· 15
.15
.16
.16
· 17
•... 19
· .20
141 Locations. . . . . • . . . • . . . . . . . • . . . • 22
161 Video Adjustments . . . . . . . . . . . . . . 22
Brightness Limiter Potentiometer. . . . • . . . . • . . • 23
Contrast Control and Brightness Control. . . . . . • . 23
Video Gain/Video Drive Potentiometer • . . . . . . . . • . • . 23
163 Vertical Adjustments • . . . . . . . . . • . . . . . • . • • • . . 24
Vertical Hold Potentiometer. . . . . . . . . . . . . • • . . . . • 24
Vertical Height Potentiometer. . • . . . . . . . . . . 24
Vertical Linearity Potentiometer. . . • . • . . . . 24
Linearity Phase Potentiometer . . . . . . • 24
165 Horizontal Adjustments. . . . . . . . . . . . 25
Horizontal Width Potentiometer . . . . 25
Horizontal Centering Potentiometer . . . 25
167 Yoke Adjustment . . . . . . . . . . . . . . . . • . . . . 26
169 Centering Adjustment. . . . . . . . . . . . • . • 27
171 Factory Adjustments . • . . . . . • . . . • . . 27
Focus Potentiometer . . . . . . . . . . . • • 27
B+ Potentiometer. . . . . . . . . . . . . • . • . 27
Page of SY31'()600-1
As updated January 30, 1981
By TN L SN20-9543
Contents
180 Glare Shield Removal and Replacement . . .
181 Display Assembly Removal and Replacement
183 Display Screen Examples • . . . . . . .
KEYBOARD/DISPLAY CARDS
· .29
· .30
· .32
200 Keyboard/Display MPU Card (A-A 1) . . .. 33
201 Data Station Adapter Card (A-E1). . . . . . 34
203 Dual Data Station Adapter Card (A-E1) . . . 35
207 Keyboard/Display Storage Cards (A-B7) . . . 37
209 Buffer Timer Card (A-B1) . . . . . . . . . . . . . . . . . . . • 37
217 Display Cable Diagram . . . . . . . . . . . . . . . . 38
219 Keyboard Cable Diagram . . . . . . . . . . . . . . . . . . . . . 40
220 Keyboard Logic Card J02 and J03 Connector . . . . . . . . . 43
227 IBM 5285 to IBM 5281 or IBM 5282 Cable Diagram . • . . . 44
229 Keylock Cable Diagram. . . . . . . . . . . .47
DISKETTE DRIVE
301 Diskette Drive Removal and Replacement
303 Diskette/Main MPU Card (A-C1) . . . . . . .
305 Diskette Driver/Receiver Card (A-D1). . . . . .
313 IBM 5285 Local Diskette Drives (Addresses 4000 and
4400) . . . . . . . . . . . . . . . . . . . . . . . • . . . . . .
319 IBM 5285 to Remote Diskette Drives (Addresses 4800
and 4COO) . . . . . . . . . . . . . . .
MAIN STORAGE AND MAIN MPU
402 Feature Main MPU Card (A-E5) .
403 Feature Main Storage Card (A-B5).
POWER SUPPLY
451 Locations . . . .
453 AC Distribution
.48
.50
.53
.54
.56
.58
•. 59
.61
.62
455 DC Distribution .64
457 Power Supply Wiring Diagram . . . . 66
458 Logic Board Distribution. . . . . 68
461 Voltage Level Checks. . . . . . . . . .. 69
463 Ripple Voltage Level Check . . . . . . . . . . . . . . . 71
470 Power Supply Removal and Replacement . . . . . . . . . . . 72
471 Communications Feature Power Supply Card Removal and
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • 74
474 Board Assembly Removal and Replacement. . . . . . . 75
476 Resonant Capacitor C7 Removal and Replacement. . . 76
POWER CORD AND LINE FILTER
480 flemoval and Replacement . . . . . . . . . . . . . . . . • 77
LOGIC AND CARDS
501 Card Plug Chart . . . . . . . . . . . . . . . . . . . • . . . . . • 79
503,"Gard Options . . . . . . . . . . . . . . . . . . . . . • . . . . . • 80
505 Logic Board and Logic Card Part Numbers.. • . . . . . . 81
513 Logic Card Cover Removal and Replacement . . . • . . . . • 86
515 Fan Shroud Removal and Replacement. . . . . 88
521 Logic Board Removal and Replacement . . • • .• 89
523 Logic Card Removal and Replacement . . . . . . 90
525 Fan Removal and Replacement . . . . . . • . . . 91
531 Net List. . . . . . . . . . . . . . . . . . . . . . . . . • . 92
561 ROS Patch Card Locations and Cables . . . . .
563 ROS Patch Card Removal and Replacement ..
565 ROS Patch Card Identification . . . . . . . . . . .
101
102
104
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