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

In addi t ion to the usual care tha.t should be taken wi th a
flexible disk, take the following extra precautions with the
alignment flexible disk.
• Before making adjustments, acclimate the flexible
disk for one hour in the working environment.
• Keep the disk drive in the "power-on" status for one
hour.
• Do not allow the flexible disk to remain immobile
under a head load condition for long.
• Use the flexible disk in a temperature range of 68
to 78.5°F
(20°
to 26°C).
5.4.1 Head Radial Alignment Check or Adjustment
Set the oscilloscope to the settings shown in Table 5-3,
then perform the head radial alignment as follows.
Table 5-3 Head Radial Alignment Oscilloscope Settings
ITEM SETTING
Channel 1
Channel 2
Mode
Inputs
Input range
Test points
Tr igger
Time base
Probes
Normal
Inverted
Add
Ac
100 mV/division
TP8 and TP9
TP7 (dual-sided media)
TPIO (single-sided media)
20 ms/division
xl or xlO
a. Insert the alignment flexible disk and step the
carriage (with the drive tester) from track 00 to
track 38.
b. Load the read/write heads for three minutes.
5-4