Index Burst Verification And Adjustment; Track 00 Sensor Adjustment - Panasonic JU-253-T Service Manual

caseofB>C (+)
B-C
Azimuth = B _ D
x
(A)
(A) : CE-+30'
DAD-+15'
Fig. 9.4 Azimuth Waveforms
9.8 Index Burst Verification and Adjustment
Case of C>B(-)
C-B
Azimuth
=
C _A
x
(A)
(1) Insert an alignment diskette. Seek to the track specified in the llB column of Table 8.1.
(2) Set the oscilloscope time base as follows:
1 ms/division
(3) Check that the time from oscilloscope start to the first data pulse meets the l/B specifications of Table
8. 1. (DAD system)
(4) If Index Burst is not within specification, adjust the variable resister on the motor control PCB.
J
I
o( • ,
Index Burst
Fig. 9.5 Index Timing
9.9 Track 00 Sensor Adjustment
[In the case of JU-252A/JU-253A]
(1) Set the oscilloscope as follows.
Set horizontal deflection to 1ms/division.
CH1 ZP
EXT SP
V.R
Fig. 9.6 l/B Adjustment
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