Panasonic JU-253-T Service Manual page 14

(2) Step between specified tracks as shown in the FLAG 0 item of Table 8.1 (Turn the seek delay switch on
the exerciser to adjust 12 ms seek.)
(3) Loosen the track 0 sensor screw and adjust until the waveform on the oscilloscope appears as shown in
Fig. 9.7.
, ; . . _ - - - - 1 - - - - - - - 1 - - - - -
VL
A
B
ADJUST A: B TO 1 : 1
Fig. 9.7 Track 0 Waveform
1 . !~illllll!lllt 1 ~ ll:~.'lil·-~·11~tlB-l!i.1/~~:
[ 1] Set the oscilloscope as follows.
Set horizontal deflection to
1
ms/division.
CH1 : ZP
EXT : Step (No. 20 Pin of CMOSITTL Adaptor)
(2) Step between specified tracks as shown in the FLAGO item of Table
8.1,
(Turn the seek delay switch on
the exerciser to adjust 3 ms seek.}
(3) Loosen the screw for track 0 assembly so that the waveform on the osciloscope is as shown in Figure 9.8
and adjust the track 0 assembly position by moving it back and forth.
STEPLJ
3.0ms
Tzp
LJ
.1
O.Bms Max
(Reference)
CP
Vcp
- - - - - - - - - - - - - - ' - - - - - - - - - GND LEVEL
Fig. 9.8 Track 0 Waveform
(4) VoltagesfTimings for track 0 waveform
1. Tzp 4.2ms
2.
VL
:;;;; 1.0V
3.
VH
~4.0V
4.
Vcp
~3.2V
-11 -