Radio Shack TRS-80 Service Manual page 3

SECTION
NUMBER
VII
VIII
IX
TABLE OF CONTENTS (Cont'd)
VIDEO MONITOR . . . . . . . . . . . • . . . _ _ .
Functional Specifications . . . . . . . . . . . . . . . . . . • . . .
Se...,ice Adjustments .
ILLUSTRATED PARTS CATALOG
Illustrated Parts Catalog Parts list
MINI·DISK DRIVE .
General Description . . . . . . . . . . . . . • . . . . . . . . . . .
Introduction . . . . . . . . . . . . . . . • • . . . . . . . . . . .
Important Notice . . . . . . . . • • • . . . . . . . . . . . . . .
Physical Description . . . . . . . • . . • . . . . . . . . . . . .
Functional Desaiption . . . . . . . . • . . • . . . . . . . . .
Interface Connections . . . . . . . . • . • • • . . . . . . . . .
Physical Checkout . . . . . . . . . . . • • . • . . . . . . . . .
Mounting the Disk Drive . . . . . . . • • . • . . . . .
Resistor Termination . . . . . . . . . . • • . • . . . . . . . . .
Flat Ribbon Cable Assembly .
Theory of Openrtion .
Introduction .
Organization of the Disk Drive .
Functional Block Diagram Description .
Indell Pulse .
Write Protect .
Track
00
Switch : .
Spindle Drive . . . . . . . . . . . . . . . . . • . • . . . . . .
Positioner Control .
Data Electronics . . . . . . . . . . . • • . • . . . . . . . . . . .
Data Recording .
Data Reproduction .
Operation .
Interface Electronics Specifications . . . . . . • . . . . . .
Input Control Lines .
SELECT Lines IDS'- - DS4-) .
Drive Motor Enable (MOTORQN) .
Direction and Step (DIA-) (STEP-' .
Compensated Write Data (CWO) . . • . . . . .
Write Enable (WG-) .
Side Select (SDSE L) .
Output Status .
Index Pulse liP') .
TRACK OOITAKO-j . . . . . . • . . . . . . • . . . . . . . . .
Write Protect (WPRT', .
Read Data (RD-) . . . . . . . . . . . . . . . . . • . . . . . . .
Maintenance .
Physical Oesaiption of the PC Boards .
Circuit Board Test Points .
Option Select .
Input Line Terminations . . . . • • . . . . . . . . . . . . .
Pr...entive Maintenance .. _ . . . . . . . • • • . . . . . . . . . .
Cleaning the Head . . . . . . . . . . . . • • . . . . . . . . . . .
Alignment anet Adjustment .
Drive Motor Maintenance .
Carriage Movement Check .
Head Radiel Alignment/CE Alignment .
Track 013 Alignment .
Index Sector Adjustment .
Head Amplitude/Compliance Oleck .
PAGE
NUMBER
73
7S
77
79
8.
91
93
93
93
.3
93
93
94
9.
9.
9.
97
97
97
97
97
97
97
97
97
98
. . . .
101
101
101
101
101
101
101
101
103
103
103
103
103
103
lOS
lOS
lOS
lOS
lOS
108
108
108
108
108
109
110
110
111