Service manual

DOU8LE·DEItIITY DISK CONTROlLER --- ..... 1
111
General Drive/Controller Diagnostic 4-11
Initiating the General Drive/Controller Diagnostic 4-11
Available Tests
and Options 4-12
F.,...Format Disk Surface ...........................•............... 4-12
T-Drive Speed , , 4·13
D-General Drive Checkout ................................•.... ,. 4-14
M-Media Check 4-15
S-Seek Time 4-15
A-Align " " 4-16
U-Switch 4-17
E-Exit ...................................................•...... 4-17
SERVICE , 5-1
Recalibration 5-1
VCO Bias Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.2
VCO Center Frequency Adjustment
(with Frequency Counter)
5-2
VCO Center Frequency Adjustment
(with Oscilloscope)
5-4
Precomposition Adjustment 5-4
In Case of Difficulty ,.................. 5-5
Decimal to Octal to Hex to ASCII Conversion , , 5·6
REPLACEMENT PARTS LIST '"
6-1
SEMICONDUCTOR IDENTIFICATION CHART 7-1
CIRCUIT BOARD X-RAY VIEW ,. 8-1
SCHEMATIC " ., Fold-in