Kenwood 1050MD Service Manual page 13

(Traverse waveform)
Specification : A = B
16. Press the ENTER key to display "EFB=##XSAVE"
momentarily and save the adjustment result in non-
volatile memory. After that, "EFBAL ADJUST" is dis-
played.
17. Press the EJECT key to take out test disc TGYS-1.
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
(TE2)
10pF
(VC)
5-7 Focus bias adjustment
Connection :
1. Insert a continuously recorded disc (refer to 5-4, "Creat-
ing the recordable continuous recording disc").
2. Turn the JOG DIAL to display "CPLAY MODE".
3. Press the ENTER key to display "CPLAY MID".
4. Press the DELETE key when "C=#### a=##" is dis-
played.
5. Turn the JOG DIAL to display "FBIAS ADJUST".
6. Press the ENTER key to display "a=## ####/##". The
middle four-digit figure indicates the C1 error rate, the
two-digit figure after "/##indicates ADIP error" , and the
two-digit figure after "a=" indicates the focus bias value.
7. Turn the JOG DIAL clockwise and detect the focus bias
value in which the C1 error rate becomes 220.
8. Press the ENTER key to display "b=## ####/##".
9. Turn the JOG DIAL counterclockwise and detect the
focus bias value in which the C1 error rate becomes
220.
10. Press the ENTER key to display "C=## ####/##".
11. Confirm that the C1 error rate at that time is less than
50, then press the ENTER key.
12. The display appears "##-##-##(##)" momentarily and
save the adjustment result in nonvolatile memory. After
that "FBIAS ADJUST" is displayed.
13. Press the EJECT key to take out a continuous recording
disc.
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.
CIRCUIT DESCRIPTION
Oscilloscope
+
-
1050MD/DM-5090/DM-9090
2. The C1 error rate fluctuates. Therefore, perform the
adjustment according to the observed mean value.
C1 error
5-8 Error rate confirmation
5-8-1 CD error rate confirmation
Confirmation :
1. Insert test disc TGYS-1.
2. Turn the JOG DIAL to display "CPLAY MODE".
3. Press the ENTER key to display "CPLAY MID".
4. "C=#### a=##" is displayed.
5. Confirm that the C1 error rate is less than 20.
6. Press the DELETE key to stop the playback, than press
the EJECT key to take out a test disc.
5-8-2 MO error rate confirmation
1. Insert a continuously recorded disc ( refer to 5-4, "Creat-
ing the recordable continuous recording disc")
2. Turn the JOG DIAL to display "CPLAY MODE".
3. Press the ENTER key to display "CPLAY MID".
4. "C=#### a=##" is displayed.
5. Confirm that the C1 error rate is less than 50 and that
ADIP error rate is 00.
6. Press the DELETE key to stop the playback, then press
the EJECT key to take out a test disc.
Note : The "#" display on the screen indicates an arbitrary
figure.
Focus bias value
13