MDS-NT1
9.Click the [ENTER/YES] to display “EFB = 
10.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not click the [JOG UP] or
[JOG DOWN].
Traverse Waveform
A
VC
B
Specified value : Below 10% offset value
Offset value (%) = I A – B I X 100 2 (A + B)
11.Click the [ENTER/YES] to display “EF MO CHECK (C14)”. The disc stops rotating automatically.
12.Click the [EJECT] button and take out the disc.
13.Load the check disc (MD)
14.Click the [JOG UP] or [JOG DOWN] and display “EF CD CHECK” (C15).
15.Click the [ENTER/YES] to display “EFB = 
CD”. Servo is imposed automatically.
16.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not click the [JOG UP] or
[JOG DOWN].
Traverse Waveform
A
VC
B
Specified value : Below 10% offset value
Offset value (%) = I A – B I X 100 2 (A + B)
17.Click the [ENTER/YES] to display “EF CD CHECK” (C15).
18.Click the [EJECT] and take out the check disc (MD)
Check Location: BD board (see page 35)
5-7-7. Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Checking Procedure:
1.Load the test disk
2.Click the [JOG UP] or [JOG DOWN] to display “CPLAY2 MODE” (C36).
3.Click the [ENTER/YES] to display “CPLAY2MID”.
4.Click the [MENU/NO] when “C = 
AD = 
” is displayed.
5.Click the [JOG UP] or [JOG DOWN] to display “FBIAS CHECK” (C16).
6.Click the [ENTER/YES] to 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 20 and ADER is below 2.
7.Click the [ENTER/YES] to display “ 
/
b = 
”. Check that the C1 error is about 100 and ADER is below 2.
8.Click the [ENTER/YES] to display “ 
/
a = 
”. Check that the C1 error is about 100 and ADER is below 2.
9.Click the [MENU/NO], then click the [EJECT] and take out the test disc.
5-7-8. C PLAY Check
MO Error Rate Check
Checking Procedure:
1.Load the test disk
2.Click the [JOG UP] or [JOG DOWN] to display “CPLAY2 MODE” (C36).
3.Click the [ENTER/YES] to display “CPLAY2MID”.
4.The display changes to “C = 
AD = 
”.
5.If the C1 error rate is below 20, check that ADER is 00.
6.Click the [MENU/NO] to stop playback, then Click the [EJECT] and take out the test disc.
CD Error Rate Check
Checking Procedure:
1.Load the check disc (MD)
2.Click the [JOG UP] or [JOG DOWN] to display “CPLAY2 MODE” (C36).
3.Click the [ENTER/YES] to display “CPLAY2MID”.
4.The display changes to “C = 
AD = 
”.
5.Check that the C1 error rate is below 20.
6.Click the [MENU/NO] to stop playback, then click the [EJECT] and take out the check disc.
5-7-9. Self-Recording/playback Check
Prepare a continuous recording disc using the unit to be repaired and check the error rate.
Checking Procedure:
1.Load a recordable disc (blank disc).
2.Click the [JOG UP] or [JOG DOWN] to display “CREC 2MODE” (C37).
3.Click the [ENTER/YES] to display “CREC 2MID”.
4.When recording starts and display “CREC 2 @@@@” (@@@@ is the address).
5.About 1 minute later, click the [MENU/NO] to stop continu- ous recording.
6.Click the [JOG UP] or [JOG DOWN] to display “CPLAY2 MODE” (C36).
7.Click the [ENTER/YES] to display “CPLAY2MID”.
8.“C = 
AD = 
” will be displayed.
9.Check that the C1 error becomes below 20 and the AD error below 2.
10.Click the [MENU/NO] to stop playback, then click the [EJECT] and take out the disc.
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