Cd Section - Sony ZS-M50 Service Manual

C1 error
220
b
c
5-9. ERROR RATE CHECK
5-9-1. Pit disk error rate check
Procedure:
1. Insert the check disk (MD) TDYS-1
2. Turn the AMS dial until " CPLAY MODE " is displayed.
3. Press the YES/ENTER button to display " CPLAY MID ".
4. The display will change to " C1=
5. Check to see that the C1 error rate is less than 20.
6. Press the NO/CANCEL button to stop playback, then press the
MD EJECT button to remove the check disk (MD).
5-9-2. MO error rate check
Procedure:
1. Insert a continuously recorded disk (see 5-4. Creating a con-
tinuous recording disk).
2. Turn the AMS dial until " CPLAY MODE " is displayed.
3. Press the YES/ENTER button to display " CPLAY MID ".
4. The display will change to " C1=
5. Check to see that the C1 error rate is less than 50 and ADER is
constantly not above 00.
6. Press the NO/CANCEL button to stop playback, then press the
button to remove the continuously recorded disk.
5-10. FOCUS BIAS CHECK
The focus tolerance volume is checked by changing the focus bias
volume.
Procedure:
1. Insert a continuously recorded disk (see 5-4. Creating a con-
tinuous recording disk).
2. Turn the AMS dial until "CPLAY MODE" is displayed.
3. Press the YES/ENTER button to display "CPLAY MID".
4. When "C1= AD=
CEL button.
5. Turn the AMS dial until "FBIAS CHECK" is displayed.
6. Press the YES/ENTER button to display "
The first 4 digits indicate the C1 error, the 2 digits following " /
" indicate ADER and the 2 digits following "c=" indicate the
focus bias volume.
At this time, check to see that the C1 error is less than 50 and
ADER is 00.
7. Press the YES/ENTER button to change the display to "
b= "
At this time check to see that the C1 error is not less than 220
and ADER is constantly not above 00.
8. Press the YES/ENTER button to change the display to "
a= "
At this time check to see that the C1 error is not less than 220
and ADER is constantly not above 00.
9. Press the NO/CANCEL button, then press the MD EJECT but-
ton to remove the continuously recorded disk.
Note 1: If the C1 error or ADER is more than 00 for only one of
points a (8. above) and b (7. above), there is the possibility
of a gap in the focus bias adjustment. In such case, repeat
adjustment.
Focus bias volume
(F, BIAS)
a
AD= ".
AD= ".
" is displayed, press the NO/CAN-
/ c=

CD SECTION

1. Enter the CD Test mode
(see page 19)
88 07 00 3A0
The above is the default display.
Pressing the ^ button will rotate the CD and pressing the YES/
ENTER button once more will output sounds.
Pressing the YES/ENTER button will execute automatic adjust-
ment and values will change; however, this value is quite nor-
mal.
2. RF LEVEL and jitter check
Test mode PLAY status ("21" and "ALL" display ON)
21 07 00 3A0
ALL display ON : LPC (laser power control ON)
ALL display OFF : LPC (laser power control OFF)
(^ button : ALL display ON/OFF)
Connection Point:
[MAIN BOARD] (SIDE A)
Oscilloscope
".
TP (RFO)
Check to see that the jitter is less than 9.0 nsec.
and RF level is between 1.0 – 1.5Vp-p.
/
VOLT/DIV : 200mV (using 10:1 probe)
TIME/DIV : 500ns
/
– 24 –
ALL
TP(VC)
RF level:
1.0 - 1.5Vp-p