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43
6-6-8. C PLAY Check
MO Error Rate Check
Checking Procedure :
1. Load a continuously recorded test disc (MDW-74/GA-1).
(Refer to “6-5. Using the Continuously Recorded Disc”.)
2. Move the multi-stick and display “CPLAY1MODE”(C34).
3. Press the PUSH ENTER button and display “CPLAY1MID”.
4. The display changes to “C1 =
AD =
”.
5. If the C1 error rate is below 20, check that ADER is 00.
6. Press the CLEAR button while REC IT is lit, stop playback,
press the MD
Z
button while REC IT is off, and test disc.
CD Error Rate Check
Checking Procedure :
1. Load a check disc (MD) TDYS-1.
2. Move the multi-stick and display “CPLAY1MODE”(C34).
3. Press the PUSH ENTER button twice and display “CPLAY1
MID”.
4. The display changes to “C1 =
AD =
”.
5. Check that the C1 error rate is below 20.
6. Press the CLEAR button while REC IT is lit, stop playback,
press the MD
Z
button while REC IT is off, and the test disc.
6-6-9. 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 test disc (MDW-74/GA-1) into the unit.
2. Move the multi-stick to display “CREC 1MODE”(C35).
3. Press the PUSH ENTER button to display the “CREC 1MID”.
4. When recording starts, “
MD REC
” is displayed, this becomes
“CREC (@@@@)” (@@@@ is the address), and recording
starts.
5. About 1 minute later, press the CLEAR button to stop continu-
ous recording while REC IT is lit.
6. Move the multi-stick to display “CPLAY1MODE”(C34).
7. Press the PUSH ENTER button to display “CPLAY1MID”.
8. “C1 =
AD =
” will be displayed.
9. Check that the C1 error becomes below 20 and the AD error
below 2.
10. Press the CLEAR button to stop playback while REC IT is lit,
and press the MD
Z
button while REC IT is off and remove
the disc.
330 k
Ω
Oscilloscope
10pF
BD (MD) board
CN105 pin
4
(TE)
CN105 pin
6
(VC)
6-6-7. Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Checking Procedure :
1. Load a continuously recorded test disc (MDW-74/GA-1).
(Refer to “6-5. Using the Continuously Recorded Disc”.)
2. Move the multi-stick and display “CPLAY1MODE”(C34).
3. Press the PUSH ENTER button and display “CPLAY1MID”.
4. Press the CLEAR button while REC IT is lit when “C =
AD =
” is displayed.
5. Move the multi-stick and display “FBIAS CHECK”(C16).
6. Press the PUSH ENTER 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 20 and ADER is below 2.
7. Press the PUSH ENTER button and display “
/
b =
”.
Check that the C1 error is below 100 and ADER is below 2.
8. Press the PUSH ENTER button and display “
/
a =
”.
Check that the C1 error is below 100 and ADER is below 2.
9. Press the CLEAR button while REC IT is lit, next press the
MD
Z
button while REC IT is off, and remove the test disc.
16. Observe the waveform of the oscilloscope, and check that the
specified value is satisfied. Do not move the Multi stick.
(Traverse Waveform)
17. Press the PUSH ENTER button and display “EF CD CHECK”
(C15).
18. Press the MD
Z
button while REC IT is off and remove the
check disc (MD) TDYS-1.
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.
VC
A
B
Specified value : Below 10% offset value
Offset value (%) = X 100
I
A – B
I
2 (A + B)
Summary of Contents for HCD-VZ50MD
Page 8: ...8 BD CD board BD CD BOARD To repair the BD CD board remove the bottom plate Bottom view ...
Page 57: ...HCD VZ50MD 57 57 7 4 SCHEMATIC DIAGRAM DECK SECTION E Page 64 TO MAIN BOARD 16 ...
Page 64: ...HCD VZ50MD 64 64 7 11 SCHEMATIC DIAGRAM MAIN 1 4 SECTION ...
Page 65: ...HCD VZ50MD 65 65 7 12 SCHEMATIC DIAGRAM MAIN 2 4 SECTION See page 89 for IC Block Diagrams ...
Page 67: ...HCD VZ50MD 67 67 7 14 SCHEMATIC DIAGRAM MAIN 4 4 SECTION See page 89 for IC Block Diagrams ...
Page 71: ...HCD VZ50MD 71 71 7 18 SCHEMATIC DIAGRAM DIGITAL 2 2 SECTION See page 92 for IC Block Diagrams ...
Page 73: ...HCD VZ50MD 73 73 7 20 SCHEMATIC DIAGRAM AMP SECTION ...
Page 77: ...HCD VZ50MD 77 77 7 24 SCHEMATIC DIAGRAM SWITCH SECTION ...
Page 83: ...HCD VZ50MD 83 83 7 32 SCHEMATIC DIAGRAM POWER SUPPLY SECTION ...