Adjustment Of Off-Track - Epson QX-10 Technical Manual

3.4.3 Adjustment of off-track
~~"'----'7f:7~--";;':~-lnterruPter
fixing screw
A) Tools to be used
1 ) (
+ )
screwdriver #
2) CE disk
3) Osciloscope
4) FDD Controller
Fig. 3-4 Adjustment of off-track
B) Procedure
1) Make connections between CH 1 of the oscilloscope and TP2, CH 2 and TP3 and the external trigger
and TP7, respectively.
(The trigger should be in the positive direction.)
2) Set the oscilloscope signal conditions as specified below.
Switch CH 1 CH 2
AC-GNO-OC
AC AC
VERT MODE ADD
INVERT
-
ON
VOLT lOIN (on the screen) 50mV 50mV
TIME/OIV 20mS
Table. 3-3
3) Rotate the disk drive motor.
4) Set the CE disK.
5) Move the head to track 34.
6) Observe the waveforms on the oscilloscope.
Fig.3-5 TP2
+
TP3
7) When the ratio (small/large) of the waveforms A to B in Fig. 3.5 is lower than 0.7, tighten the inter-
rupter fixing screws (2) on the VCM unit.
8) Move the interrupter forward and backward using the ( - ) screwdriver so that the ratio of A to B
becomes 1 -- 0.7.
9) Tighten the interrupter fixing screw taking care not to move the adjusted position of the interrupter.
10) Apply Neji-Iock green to the interrupter fixing screw. (Seea 3.5.6.)
3-5