Kenwood RD-M52MD Service Manual page 9

7-7 EF Balance(Traverse Adjustment)
Connection :
X33
ADJUSTMENT
TE1
VC
1. Recordable Disc
No. Key
1 Connect the oscilloscope to TE1 and VC in X33 pcb
2 Volume/ Select [EFBAL ADJU]
multi-control
3 Load the recordable disc
4 PLAY [EFBAL MO-W]
5 PLAY [EF=$ MOW]
6 Volume/ Write power adjustment. Adjust the waveform as follows.
multi-control
7 PLAY Display shows [EF=$
to save the data in E2PROM.
Mode changes write to read
Focus and disc servo are on. Tracking servo off.
8 Volume/ Read power adjustment. Adjust the waveform as follows.
multi-control
9 PLAY Save the data in E2PROM.
Display shows [EFBAL MO-P]
PLAY Display shows [EF=$
(Pickup travels to search pits and tune the servo to on.)
10 Volume/ Adjust the waveform as follows.
multi-control
11 PLAY Display shows[EFB=
to save the data in E2PROM.
Display shows [EFBAL CD] disc motor stops.
12 EJECT Unload disc.
2. Pre Master Test Disc(TGYS-1)
No. Key
1 Load the disc(TGYS-1).
2 PLAY [EF=$ CD] servo is on
3 Volume/ Adjust the waveform as follows.
multi-control
4 Save the data in E2PROM.
Display shows[EFB=
[EFBAL ADJU]
5 EJECT Unload disc.
During this adjustment, the oscilloscope changes in units
of about 2%. Adjust so that the waveform comes nearest
to the specified value. (MO groove read power traverse
adjustment)
(Traverse waveform)
Specification : A = B
Notes :
1. Data is erased during MO write when a recorded disc is
used for this adjustment.
2. If the traverse waveform is difficult to be monitored, con-
nect an oscilloscope as shown in the figure below.
330kΩ
(TE1)
(VC)
CIRCUIT DESCRIPTION
Oscilloscope
+
-
V: 0.5V/div H: 10ms/div
INPUT: DC mode
Display/Function
MOR] after [EFB= xSAVE]
MOP]
xSAVE]
Display/Function
xSAVE] in brief time.
Oscilloscope
+
-
10pF
RD-M52MD/M72MD
7-8 Focus Bias Adjustment
Use the special disc(continuous recorded disc)
No. Key
1 Volume/multi-control Select [FBIAS ADJU]
2 Load the disc.
3 PLAY [a=xx yyyy/] point a
(xx=focus bias, yyyy=C1error)
4 Volume/multi-control Adjust "yyyy" to 220
5 PLAY [b=xx yyyy/] point b
6 Volume/multi-control Adjust "yyyy" to 220
7 PLAY [xx yyyy/] point c
Check "yyyy" within 50
8 PLAY Display shows [aa bb cc(xx)] focus bias adjust
(aa= point a,bb=b,cc=c )
* Notes :
1. The relation between the C1 error and focus bias value
is shown in the figure below. Points "a" and "b" in the
figure are detected by the above adjustment. Focal
position "C" is automatically obtained from points "a"
and "b" by calculation.
2. The C1 error rate fluctuates. Therefore, perform the
adjustment according to the observed mean value.
C1 error
7-9 Error Rate Check
No. Key
1. CD Error Rate
1 Volume/ [CPLAY MODE]
multi-control
2 Load the test disc(TGYS-1)
3 PLAY Display shows [CPLAY MID]
Access end
[c=xxxx a=yy] xxxx=C1 error (lower 20) yy=AIDP error
4 STOP [CPLAY MODE]
5 EJECT Unload disc.
2. MO Error Rate
No. Key
1 Volume/ [CPLAY MODE]
multi-control
2 Load the recordable disc
3 PLAY Display shows [CPLAY MID]
Access end
[c=xxxx a=yy] xxxx=C1 error (lower 50) yy=AIDP error(00)
4 STOP [CPLAY MODE]
5 EJECT Unload disc.
Display/Function
Focus bias value
Display/Function
Display/Function
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