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— 24 —
When a general remote commander is used:
1.
Press the
1/u
button to turn ON the power.
2.
Open the front cover, and press the CD PLUS ONE button.
3.
Set the disc (YEDS-18) into the “PLUS ONE” slit.
4.
Close the front cover, and chuck the disc.
5.
Press the
1/u
button to turn OFF the power.
6.
Connect the oscilloscope to TP (TE) of the BD board.
7.
Connect TP (ADJ) of the MAIN board and connect TP (GND)
with a lead wire.
8.
Press the
1/u
button to 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 oscilloscope's waveform and the A
(DC voltage) of the center of the Traverse waveform.
Confirm the following :
A/B x 100 = less than ± 10%
10. Confirm that oscilloscope waveform is clear and check RF signal
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.
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.
CD SECTION
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 10 MW impedance.
4.
Clean the object lens by an applicator with neutral detergent
when the signal level is low than specified value with the
following checks.
S Curve Check
Procedure :
1.
Press the
1/u
button to turn ON the power .
2.
Open the front cover, and press the CD PLUS ONE button.
3.
Set the disc (YEDS-18) into the “PLUS ONE” slit.
4.
Close the front cover, and chuck the disc.
5.
Press the
1/u
button to turn OFF the power.
6.
Connect the oscilloscope to TP (FE) of the BD board.
7.
Connect TP (ADJ) of the MAIN board and connect TP (GND)
with a lead wire.
8.
Press the
1/u
button to 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
between 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
1/u
button to turn ON the power.
2.
Open the front cover, and press the CD PLUS ONE button.
3.
Set the disc (YEDS-18) into the “PLUS ONE” slit.
4.
Close the front cover, and chuck the disc.
5.
Press the
1/u
button to turn OFF the power.
6.
Connect the oscilloscope to TP (RF) of the BD board.
7.
Connect TP (ADJ) of the MAIN board and connect TP (GND)
with a lead wire.
8.
Press the
1/u
button to turn ON the power.
9.
Playback the fifth track of the disc.
oscilloscope
BD board
TP (FE)
TP (VC)
S-curve waveform
symmetry
within 1.8
±
0.6Vp-p
A
B
oscilloscope
BD board
TP (RF)
TP (VC)
RF signal waveform
level : 1.8
±
Vp-p
VOLT/DIV : 200mV
TIME/DIV : 500ns
+0.3
–0.2
TP (TE)
TP (VC)
BD board
oscilloscope
Traverse waveform
A (DC voltage)
B
Center of the waveform
level : 0.7
±
0.3 Vp-p
0V
Traverse waveform
0V
C (DC
voltage)
Tracking servo
Sled servo
ON
Tracking servo
Sled servo
OFF