Sony SCD-XA777ES Service Manual page 29

RF Level Check
Connection:
MAIN board
TP703 (RFAC)
TP704 (AGND)
Checking Method:
1. Under the condition of traverse waveform check mode in step
[ AMS
l L
4, press the
2. Connect an oscilloscope to the TP703 (RFAC) and TP704
(AGND) on the MAIN board.
3. After "WAIT" is displayed, the RF waveform check mode will
become active and "PLAY 5th" will be displayed, and the 5th
music on the disc will be played.
4. Check that the RF waveform is clear and the level satisfies the
specification.
[ AMS ]
l L
5. Press the dial, and "GAISHU" will be displayed
and the outward track of the disc will be played.
6. Check that the RF waveform is clear and the level satisfies the
specification.
[ AMS ]
7. Press the l L dial, and "NAISHU" will be displayed
and the inward track of the disc will be played.
8. Check that the RF waveform is clear and the level satisfies the
specification.
[
9. After checking, press the
over when "BU MEASURE" is displayed.
[OPEN/CLOSE]
10. Press the
the test disc.
11. Using each type of disc, repeat from step 1 of S curve wave-
form check up to step 10 of RF level check.
12. When the check is over, press the
power off.
Note: Take care not to leave the test disc in the set.
Specified Value:
Disc
A
SATD-S5 or
SATD-S4
0.9 to 1.5 Vp-p
PATD-012 or
YEDS-18
RF signal waveform
Note: Clear RF waveform refers to the waveform where ◊ shapes should
be distinctively observed in the center.
Checking and Connecting Location : See page 30.
oscilloscope
+
–
]
dial.
AMS ]
l L
dial, and the test is
button to open the tray, and remove
[POWER]
button to turn the
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
A
CLV Jitter Check (CD only)
Connection:
MAIN board
TP516 (RFCK)
TP517(WFCK)
TP808 (DG)
Checking Method:
1. Set the test mode.
2. Connect an oscilloscope to the TP516 (RFCK) (CH1), TP517
(WFCK) (CH2) and TP808 (DG) (GND) on the MAIN board.
3. Place the test disc PATD-012 or YEDS-18 on the tray, and
close the tray.
[ AMS ]
l L
4. Rotate the
[ AMS
l L
and press the
will be judged.
5. Check that the disc type has been judged.
(For the PATD-012, "DSKMOD CD" will be displayed. Refer
to the test mode, DISC DETECT command (page 18))
[ AMS
l L
6. Rotate the
[ AMS
l L
and press the
automatic adjustment will be carried out, and all servos will
be turned on.
[ AMS ]
7. Rotate the l L
[ AMS
press the l L
8. Check that the value A of waveform on the oscilloscope sat-
isfies the specification.
[ AMS
9. Rotate the l L
[ AMS
l
and press the
turned off and the disc rotation will stop.
[OPEN/CLOSE]
10. Press the
the test disc.
[POWER]
11. Press the button to turn the power off.
Note: Take care not to leave the test disc in the set.
Specified Value:
Disc
A
PATD-012 or
50 µsec or less
YEDS-18
CLV jitter waveform
Checking and Connecting Location : See page 30.
SCD-XA777ES
oscilloscope
(CH1)
+ +
–
(CH2)
dial to select "61 DISC DETECT",
]
dial to enter. Then, the disc type
]
dial to select "86 ALL SRV ON",
]
dial. Then, the disc will rotate,
dial to select "07 DSP MON3", and
]
dial to enter.
]
dial to select "19 ALL SRV OFF",
]
L
dial. Then, all servos will be
button to open the tray, and remove
A
29