Index Alignment Check Or Adjustment; Index Alignment Oscilloscope Settings - NEC FD1165 Maintenance Manual

a. Insert the alignment flexible disk and step the
carriage to track 76.
b. Load the heads.
c. Compare the waveform in Figure 5-4 with the waveform
that is displayed on the oscilloscope.
d. If the waveform is not wi thin specifications, re-
place the carriage assembly.
-
A B
C 0
~
SPEC IFICATION
B~AANDC~
0
Figure 5-4 Azimuth Waveform
5.4.3 Index Alignment Check or Adjustment
Set the oscilloscope to the settings in Table 5-5, then use
the following procedure to check or adjust the Index align-
ment.
Table 5-5 Index Alignment Oscilloscope Settings
ITEM SETTING
Channel 1 Normal
Channel 2 Inverted
Mode Add
Inputs Ac
Input ra.nge 200 mV/division
Test points
TP8 and TP9
Trigger TP7 (dual-sided)
TPIO (single-sided)
Time base 0.1 ms/division
Probes xl
5-7