14
SCD-XB790
How to Apply Servo by Manual Operation
In analyzing failures of the set, the servo may be applied by manual
operation. To apply servo in the test mode, use the following
method.
1. After setting the test mode, rotate the
[ AMS ]
dial to
select a command, and press the
[ AMS ]
dial to enter.
2. “61 DISC DETECT” (Disc type check)
t
“18 ALL SRV ON”
(All servos on + auto adjustment)
3. If applying servo while checking the condition one by one,
“61 DISC DETECT” (Disc type check)
t
“31 PI/FE OFSET”
(Offset automatic adjustment)
t
“14 FSRV ON/OFF” (Focus
servo on)
t
“16 CLV ON/OFF” (CLV servo on)
t
“44 ADJ
TRK DSP ” (E-F balance adjustment)
t
“15 TSRV ON/OFF”
(Tracking servo on)
t
“17 SSRV ON/OFF” (Sled servo
on)
t
“24 ADJ FCSBIAS” (Focus bias adjustment)
t
“27
FOCUS AGC” (Focus auto gain adjustment)
t
“45
TRACKING AGC” (Tracking auto gain adjustment).
Note:
1. On and off are alternately switched in the same command.
2. For a stop, select “19 ALL SRV OFF” and press the
[ AMS ]
dial.
4-1. IC INTERFACE CHECK
The communication between microcomputer and main ICs is
checked.
Checking Method:
1. After setting the test mode, rotate the
[ AMS ]
dial to
select “A0. IC SELF CHECK” and press the
[ AMS ]
dial to enter.
2. A checking will start automatically. (Checking time is about 3
seconds)
3. At successful completion of check, “IC CHECK OK” is dis-
played. In this case, no error exists in the IC interface.
Note:
The check mentioned above tests the communication from micro-
computer to main ICs. Even if the check successfully finished, the
IC to be checked is not always normal. Consider it for reference
only.
4. In case of an IC communication error, the following display
will be given during the checking. Possible causes of error are
as listed below.
Error display
Causes (typical example)
DVD DEC. ERROR
1. IC701 (SACD decoder) is faulty
2. IC701 pin
<znv
(XRST) does not go “H”
• IC901 pin
ts
(XDIS IO) does not go “H”
3. 768fs (33.8688 MHz) is not present to
(XTAL)
• IC811 (3-multiplying circuit) is faulty
• Clock signal 256fs is not sent from
qg
)
7
• CN701, 702 and FFC connection is loose,
1. IC706 (D-RAM) is faulty
2. IC701 pin
• IC904 (PLD) is faulty
3. Faulty communication line between
IC701 and IC706
• Data line, address line, WE, etc.
4. D903 (1SS367) is faulty
D+3.3V is not present to IC706
CD DSP ERROR
1. IC509 (CD DSP) is faulty
2. 768fs (33.8688 MHz) is not present to
IC509 pin
ua
(XTAL)
Same as cause 3 of DVD DEC. ERROR
3. IC509 pin
2
(XRST) does not go “H”
• IC901 pin
ts
(XDIS IO) does not go “H”
• IC904 (PLD) is faulty
Error display
Causes (typical example)
EEPROM ERROR
1. IC903 (EEPROM) is faulty
SAMBA DRAM ERR
1. IC808 (D-RAM) is faulty
(DSD decoder is also
2. IC801 (DSD decoder) is faulty
checked)
3. 768fs (33.8688 MHz) is not present to
IC801 pin
qa
(MCKI)
Same as cause 3 of DVD DEC. ERROR
4. IC801 pin
9
(XRST) does not go “H”
• IC901 pin
ts
(XDIS IO) does not go “H”
• IC904 (PLD) is faulty
5. Faulty communication line between
IC801 and IC808
• Data line, address line, WE, etc.
6. D904 (1SS367) is faulty
D+3.3V is not present to IC808
RF AMP ERROR
1. IC001 (RF AMP) is faulty
2. Loose connection between CN708 on
MAIN board and CN005 on RF board,
or FFC disconnection
CN708 pin
qj
(CLK RF), pin
qh
(DATA
RF) and pin
qg
(SDEN) must be checked
SD BUS ERROR
1. IC701 SD bus and IC801 AV decoder
interface is faulty
2. IC812 to 814 are faulty
Causes Common to Each IC:
1. Faulty communication line between microcomputer and each
IC.
Disconnected patterns, floating series resistors, bridge, etc.
2. Faulty IC supply voltage.
Particularly, check D+3.3V voltage.
3. Faulty microcomputer communication port to each IC
Note:
In case of more than two errors, the error display is switched over
one after another, thus making the reading difficult.
In such a case, press again the
[ AMS ]
dial to make a
recheck for error reading.
4-2. DISPLAY CHECK
Checking Method:
1. After setting the test mode, rotate the
[ AMS ]
dial to
select “8A. FL CHECK” and press the
[ AMS ]
dial to
enter.
2. Respective segments of fluorescent indicator tube will
automatically light up in order, and therefore check that there
is no chipped character.
3. The “INPUT REMOCON” will be displayed after the segment
check finished successfully, and then press a proper key on
the remote commander.
4. After “JOG CHECK” is displayed, the numbers of calendar
will be displayed from 1 to 15 each time the
[ AMS ]
dial is rotated clockwise.
5. After display up to 15, the numbers of calendar will
disappear in order each time the
[ AMS ]
dial is
rotated counterclockwise.
6. “TTX-1514?” will be displayed when all are cleared, and then
press the
[ AMS ]
dial.
7. Upon display of “KEY CHECK”, if a key on the display is
pressed, the corresponding segment of fluorescent indicator
tube will light up.
8. “FL TEST END” will be displayed if all keys are pressed.
Note: The keys include the
[ AMS ]
dial. If the segment that
corresponds to the pressed key does not light up, that key is faulty.
9. The test mode selection display will be back, if the
[ AMS ]
dial is pressed.
l
L
l
L
l
L
l
L
l
L
l
L
l
L
l
L
l
L
l
L
l
L
l
L
l
L
www. xiaoyu163. com
QQ 376315150
9
9
2
8
9
4
2
9
8
TEL 13942296513
9
9
2
8
9
4
2
9
8
0
5
1
5
1
3
6
7
3
Q
Q
TEL 13942296513 QQ 376315150 892498299
TEL 13942296513 QQ 376315150 892498299
