– 15 –
Note :
1. CD Block is basically designed to operate without adjustment.
Therefore, check each item in order given.
2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10MΩ impedance.
4. Clean the object lens by an applicator with neutral detergent
when the signal level is low than specified value with the fol-
lowing checks.
S Curve Check
Procedure :
1. Press the I/u button and turn ON the power supply.
2. Open the front cover, and press the [PLUSONE] button.
3. Set the disc (YEDS-18) into the “PLUS ONE” slit.
4. Close the front cover, and chuck the disc.
5. Press the I/
u button and turn OFF the power.
6. Connect the oscilloscope to TP (FE) of the BD board.
7. Connect TP (ADJ) of the DISPLAY board and the ground with
a lead wire.
8. Press the I/u button and turn ON the power.
9. The first track will be played back automatically. When the
[CHECK] button is pressed, “S JI” will be displayed on the
fluorescent indicator tube, and focus search will be repeated.
10. Check the oscilloscope waveform (S-curve) is symmetrical be-
tween A and B. And confirm peak to peak level within 1.8 ±
0.6 Vp-p.
11. Turn OFF the power, and remove the lead wire connected at
step 7.
Note: • Try to measure several times to make sure than the ratio of A : B
or B : A is more than 10 : 7.
• Take sweep time as long as possible and light up the brightness
to obtain best waveform.
RF Level Check
Procedure :
1. Press the I/u button and turn ON the power supply.
2. Open the front cover, and press the [PLUSONE] button.
3. Set the disc (YEDS-18) into the “PLUS ONE” slit.
4. Close the front cover, and chuck the disc.
5. Press the I/u button and turn OFF the power.
6. Connect the oscilloscope to TP (RF) of the BD board.
7. Connect TP (ADJ) of the DISPLAY board and the ground with
a lead wire.
8. Press the I/u button and turn ON the power.
9. Playback the fifth track of the disc.
10. Confirm that oscilloscope waveform is clear and check RF sig-
nal level is correct or not.
11. Turn OFF the power, and remove the lead wire connected at
step 7.
Note: A clear RF signal waveform means that the shape “◊” can be clearly
distinguished at the center of the waveform.
E-F Balance (Traverse) Check
The procedure for this checking method differs for when a general
remote control unit is used and not used.
When a general remote commander is used:
1. Press the I/u button and turn ON the power supply.
2. Open the front cover, and press the [PLUSONE] button.
3. Set the disc (YEDS-18) into the “PLUS ONE” slit.
4. Close the front cover, and chuck the disc.
5. Press the I/
u button and turn OFF the power.
6. Connect the oscilloscope to TP (TE) of the BD board.
7. Connect TP (ADJ) of the DISPLAY board and the ground with
a lead wire.
8. Press the I/u button and turn ON the power.
9. Playback the fifth track of the disc.
10. Press the [3] button on the remote commander. (The tracking
servo and the sledding servo are turned OFF.)
11. Check the level B of the oscilliscope's waveform and the A (DC
voltage) of the center of the Traverse waveform.
Confirm the following :
A/B x 100 = less than ± 10%
12. Press the
[8] button on the remote control unit. (The tracking
servo and sledding servo are turned ON.) Confirm the C (DC
voltage) is almost equal to the A (DC voltage) is step 11.
13. Turn OFF the power, and remove the lead wire connected at
step 7.
SECTION 6
ELECTRICAL ADJUSTMENTS
BD board
TP (FE)
TP (VC)
+
–
oscilloscope
symmetry
within 1.8
±
0.6Vp-p
A
B
S-curve waveforms
BD board
TP (RF)
TP (VC)
+
–
oscilloscope
(AC range)
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