Sony HCD-ZX50MD Service Manual page 45

16. Observe the waveform of the oscilloscope, and check that the
specified value is satisfied. Do not move the Multi stick.
(Traverse Waveform)
VC
Specified value : Below 10% offset value
IA – BI
Offset value (%) =
2 (A + B)
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.
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 "
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 "
Check that the C1 error is below 100 and ADER is below 2.
8. Press the PUSH ENTER button and display "
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.
X 100
Oscilloscope
330 kΩ
10pF
/ c =
/ b =
/ a =
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".)
A
2. Move the multi-stick and display "CPLAY1MODE"(C34).
3. Press the PUSH ENTER button and display "CPLAY1MID".
4. The display changes to "C1 =
B
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 =
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, "
"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 =
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.
".
".
AD = ".
AD = ".
MD REC
" is displayed, this becomes
" will be displayed.
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