10.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not rotate the AMS knob.
(Traverse Waveform)
A
VC
B
Specified value : Below 10% offset value
Offset value (%) = IA – BI X 100 2 (A + B)
11.Press the YES button display “EF MO CHECK” The disc stops rotating automatically.
12.Press the § button and remove the disc.
13.Load the check disc (MD)
14.Roteto the AMS knob and display “EF CD CHECK” (C04).
15. Press the | YES | button and display “EFB = | CD”. Servo is |
imposed automatically. |
| ||
16.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not rotate the AMS knob.
(Traverse Waveform)
A
VC
B
Specified value : Below 10% offset value
Offset value (%) = IA – BI X 100 2 (A + B)
17.Press the YES button and display “EF CD CHECK”.
18.Press the § button and remove the check disc (MD)
Note 1 : MO reading data will be erased during if a recorded disc is used in this adjustment.
Note 2 : If the traverse waveform is not clear, connect the oscillo- scope as shown in the following figure so that it can be seen more clearly.
Oscilloscope
BD board | 330 kΩ |
CN110 pin 3 (TE) | 10pF | ||
CN110 pin 1 | (VC) | ||
| |||
5-6-4. Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Checking Procedure :
1.Load a test disk
2.Rotate the AMS knob and display “CPLAY MODE”.
3.Press the YES button twice and display “CPLAY MID”.
4. Press the | MENU/NO | button when “C = | AD = ” is |
displayed. |
| ||
5.Rotate the AMS knob and display “FBIAS CHECK”.
6.Press the YES button and display “ 
/
c = 
”.
The first four digits indicate the C1 error rate, the two digits after [/] indicate ADER, and the 2 digits after [c =] indicate the focus bias value.
Check that the C1 error is below 220 and ADER is below 2.
7.Press the YES button and display “ 
/
b = 
”. Check that the C1 error is below 220 and ADER is below 2.
8.Press the YES button and display “ 
/
a = 
”. Check that the C1 error is below 220 and ADER is below 2.
9.Press the MENU/NO button, next press the § button, and remove the test disc.
5-6-5. C PLAY Checking
MO Error Rate Check
Checking Procedure :
1.Load a test disk
2.Rotate the AMS knob and display “CPLAY MODE”.
3.Press the YES button and display “CPLAY MID”.
4.The display changes to “C1 = 
AD = 
”.
5.If the C1 error rate is below 80, check that ADER is below 2.
6.Press the MENU/NO button, stop playback, press the § but- ton, and test disc.
CD Error Rate Check
Checking Procedure :
1.Load a check disc (MD)
2.Rotate the AMS knob and display “CPLAY MODE”.
3.Press the YES button twice and display “CPLAY MID”.
4.The display changes to “C1 = 
AD = 
”.
5.Check that the C1 error rate is below 50.
6.Press the MENU/NO button, stop playback, press the § but- ton, and the test disc.
5-6-6. Self-Recording/playback Check
Prepare a continuous recording disc using the unit to be repaired and check the error rate.
Checking Procedure :
1.Insert a recordable disc (blank disc) into the unit.
2.Rotate the AMS knob to display “CREC MODE”.
3.Press the YES button to display the “CREC MID”.
4.When recording starts, “ REC ” is displayed, this becomes “CREC (@@@@)" (@@@@ is the address), and recording starts.
5.About 1 minute later, press the MENU/NO button to stop continuous recording.
6.Rotate the AMS knob to display “C PLAY MODE”.
7.Press the YES button to display “C PLAY MID”.
8.“C1 = 
AD = 
” will be displayed.
9.Check that the C1 error becomes below 80 and the AD error below 2.
10.Press the MENU/NO button to stop playback, and press the § button and remove the disc.
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