SCD-XB780 - Sony Audio Service Manual (repair manual). Page 15

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The operational stability of the set is checked. The check and OK/NG judgment are performed automatically.

: In the set check using the CD, besides a checking, the MIRR time used for the disc check is measured every optical pick-up, and from the measured

result, the threshold value is calculated and it is stored in the EEPROM (IC903) on the MAIN board. Accordingly, if a combination of optical pick-
up and EEPROM is changed (for example, the optical pick-up or MAIN board is replaced), be sure to perform the set check using the following CD.
As the data stored in the EEPROM are overwritten every set check, retry if failed. For the set check using the SACD, only checking is made.

Checking method:
1. After setting the test mode, rotate the 

[        AMS        ]

 dial to select “SET CHECK” and press the 

[        AMS        ]

 dial to enter.

2. Upon display of “AUTO CHECK SP?”, further press the 

[        AMS        ]

 dial.

3. The tray will open automatically, and then set the test disc*1 of CD or SACD.
4. With the “DISC IN&JOG ON” displayed, press the 

[        AMS        ]

 dial, and the check will be executed automatically.

5. “SPEC OK!” will be displayed if the measured result is within the specification. Faulty item name and the measured result will be

displayed if any measured item is NG.

6. After that, “AUTO CHECK SP?” will be again displayed, and then rotate the 

[        AMS        ]

 dial to select “CHECK END?”. Further,

press the 

[        AMS        ]

 dial, and the test mode selection display will be back, and then press the 

[OPEN/CLOSE    ]

 button and take

the test disc out.

*1 Use PATD-012 or YEDS-18 for CD, and SATD-S5 or SATD-S4 for SACD (SL). Using another disc will result in a checking failure.

Items

Description

Remarks

Offset values before RF (PI), VC, FE, TE signal offset adjustment

At offset 0

RF/VC/FE/TE (ORG)

RF (8 bit data in hex notation)

RF: A0h

VC, FE, TE (9 bit data in hex notation)

VC, FE, TE: 00h

Offset values after RF (PI), VC, FE, TE signal offset adjustment

VC offset is not adjusted

RF/VC/FE/TE (ADJ)

(Less than ORG value if offset correction is normal)

(Measurement only)

RF (8 bit data in hex notation)

Also, for SACD, the TE offset is

VC, FE, TE (9 bit data in hex notation)

not measured and adjusted

PI (ORG): PI value at disc type check (decimal data)

PI level conversion

PI (ADJ): PI value after PI offset adjustment

Read value 

×

 12.9mV

(read value at microcomputer A/D) (decimal data)

PI/TRVS PP (ORG/ADJ)

TRVS PP (ORG): Traverse level before level correction (AGC)

Traverse level conversion

(decimal data)

Read value 

×

 12.9mV

TRVS PP (ADJ):Traverse level after level correction (AGC)

(decimal data)

12.9mV=3.3V 

÷

 256 (8 bit)

PIOR: Set value of PI offset coarse adjusting register

Registers in RF amplifier

PIOR/CCR/TRCR

CCR: Set value of FE offset coarse adjusting register
TRCR: Set value of TE offset coarse adjusting register

FOCUS/TRK GAIN

Auto gain adjusted values of focus and tracking servos
(8 bit data in hex notation)

FBIAS: Focus bias set value (9 bit data in hex notation)

TRCR2 adjusts the E-F gain

TRVSC: Traverse center value (9 bit data in hex notation)

balance and used for CD only

FBIAS/TRVSC/TRCR2/CFR

TRCR2: Set value of E-F balance coarse adjusting register

(Fixed to 06 for SACD)

CFR: Set value of traverse level adjusting register

TRCR2 and CFR are registers in
RF amplifier

PSP AMPLITUDE

SACD only

1-LAST TRK SEEK (msec)

Average seek time from first track to last track of disc

Error rate measurement

For the CD, Measure for 7 sec at track

ERROR RATE

For CD: Average value/Maximum value of C1 and C2

No.5

For SACD: Average value/Maximum value of PO, PI1 and PI2

For the SACD, calculation from 100-
block data at track No.5

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92. SET CHECK

AUTO CHECK SP?

AUTO CHECK?

DISP RESULT S?

CHECH END?

DISP RESULT F?

The set check is executed to judge OK or NG.
(For the CD, the threshold value is stored in the EEPROM)

The measured result is displayed on the fluorescent indicator tube.

The set check of measurement only is executed.

The measured result is displayed via RS-232C.

The set check is finished.

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