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Three crystal oscillators are used for clock output.
*X701 (16MHz): Clock for the main microprocessor (IC701).
*X1001 (8MHz):Clock for the display microprocessor (IC1002).
*X301 (45MHz): Master clock (1024fs; fs = 44.1kHz). Makes the divisions that create the clocks.

The test point for confirming the clocks is around the center of the main board. First find the appropriate place under “Indications on

Board,” below, and then confirm the clocks.

When confirming the clock, check the signal level and frequency. Normally it is only necessary to make sure that the clock is output. Even

if the signal waveform is not vertically symmetrical there is no problem.

Table 2-2. Clock Confirmation

Clock

Indication on Board

Indication on Service Manual Pattern Diagram

Terminal Position

Specified value

44. 1kHz (fs)

REF-LRCK

TP704

Pin 4 of IC715

44.1kHz+5Hz

27MHz

27MHz

JL926

FL717

27.000MHz+1kHz

22MHz (512fs)

22MHz

JL925

Pin qf of IC703

22.58MHz+500Hz

DSD decoder (IC703)

SSP (IC512)

ARP (IC702)

PLL (IC715)

PLL (IC714)

X301

IC302 (D/A converter)

PLL (IC305, IC306, IC307)

AUDIO board

1024fs (45MHz)

256fs (11.28MHz)

64fs (2.8MHz)

fs (44.1kHz)

MAIN board

27MHz

768fs (33.86MHz)

512fs (22.58MHz)

PLL (IC713)
DEVIDER ( IC710)

768fs (33.86MHz)

27MHz

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The check land for confirming PLL circuit operation is also around the center of the main board. If the circuit does not operate normally

owing to poor soldering or the like, jitter values will be outside the specified value.
Normally, it is not necessary to confirm these clock jitters.

Table 2-3. Clock Jitter

Clock

Indication on Board Indication on Service Manual Pattern Diagram

Terminal Position

Specified value

27MHz

21K-REF

TP (D1)

Pin 4 of IC713

Jitter for 2 signals is 30ns or less

21K-REF

TP (D2)

Pin 5 of IC713

512fs

REF-LRCK

TP711

Pin 4 of IC715

Jitter for 2 signals is 15ns or less

VAR-LRCK

TP (B)

Pin 5 of IC715

JL925:22MHz

JL926:27MHz

TP(D1):21K-REF

TP(D2):21K-VAR

TP704:REF-LRCK

TP711:REF-LRCK

TP(B):VAR-LRCK

IC702

IC703

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The expander’s LD SW0 and SW1 terminals (Pins 4 and 5 of IC712) check the OPEN and CLOSE switches (S003 and S004) to detect

the loading panel’s status.

Depends on the panel’s status, the expander’s LOAD and UNLOAD terminals (Pins 9 and q; of IC712) control the loading motor drive

(IC515) and the loading motor drive (IC515) rotate the loading motor and move the loading panel.

If the loading motor is rotated in the same direction for over 4 seconds and the operation still does not complete, the motor will be rotated

in the opposite direction.

The STB board’s LED (D002) and sensor (IC009) detect the stabilizer. The detection signal is input to the expander’s STBL DTC terminal

(Pin 1 of IC712).

When the loading assembly is removed, loading panel and stabilizer detection signals will not be input. Thus, set operations cannot be
confirmed. In this case, set the test mode to “ADJUSTMENT 2 MODE” and confirm operations.

The spindle motor that has chucked the disc will be moved to the side where the optical block is. With serial data from the main micropro-

cessor (IC701), the S-OUT signal will be output from the servo DSP (IC512), the sled driver (IC503) driven and the sled motor (M2) rotated.

The IN switch (S002) will detect the completion of the movement. The detection signal will be input to the expander’s SLD SW0 and

SW1 terminals (Pins 6 and 7 of IC712).

After a disc has been inserted, the SACD player will detect the disc type, make functional playback adjustments in keeping with the
disc’s features and the like. Because it takes some time to detect the disc type, it may feel as if it takes a long time until playback starts,
but this is not indicative of trouble.

Based on the following three types of detection, a disc will be judged as one of four types (CD, single layer, dual layer or hybrid).

(1)  HD layer detection
(2)  CD layer detection
(3)  SL/DL detection

When it is time for disc type detection, the tilt servo will be applied to the optical block used in detection.

HD Layer?

START

CD Layer?

CD Layer?

SL?

YES

NO

YES

DL

SL

Hybrid

NO DISC

CD

YES

NO

YES

NO

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V

TE

FD

The laser for SACDs is emitted and the existence of the HD layer (layer near the center of the disc) detected from the reflected light. At the

time of detection, the sled motor is rotated and detection is completed from the disc’s innermost to the middle part. The spindle motor is not
rotated at this time. When detection has terminated, the sled motor is rotated in reverse and returned to a position where the disc’s innermost
part can be played.

The focus drive (FD) signal that drives the focus coil and the PI signal that the disc’s reflected light generates are used in detection. The

PI signal is created from the RF signal and is output in proportion to the disc’s quantity of reflected light. Based on these signal inputs, disc
type is judged using the microprocessor (IC701).

The distance from the side of the disc that reads the signals to the HD layer is approximately 0.6mm, and the distance to the CD layer is

approximately 1.2mm. When the objective lens is raised in accordance with the focus search operation, it will first focus on the surface of the
disc, and reflected light will be detected. If the lens is move, it will focus on the HD layer in the center of the disc, and reflected light will be
detected. Lastly, it will focus on the CD layer directly on back of the labeled side, and reflected light will be detected.

In keeping, the HD layer can be detected using “T,” which is the time the disc’s surface reflection has been detected to the time the next

reflected surface is detected. If “T” is shorter than the fixed time, the judgment will be “HD layer exists.” If “T” is longer, the judgment will
be “No HD layer exists.”

All SACDs (SLs, DLs and hybrids) have an HD layer. Dual-layer discs have two HD layers near the center of the disc; as the interval

between them is extremely narrow, they will be detected similarly to a single layer.

As DVDs, DVD-ROMs and the like also have an HD layer in the center of the disc, it will be detected as “HD layer exists.”

The laser for CDs is emitted and the existence of the HD layer (layer on the back of the disc’s labeled side) detected from the reflected

light. During the detection process, the sled motor is rotated, and detection is completed while it moves from the disc’s innermost to the
middle part. At this time, the sled motor rotates at a constant speed.

The focus drive (FD) signal that drives the focus coil and the tracking error (TE) signal for tracking control are used in detection. The TE

signal is proportional to the disc’s quantity of reflected light. From these signal inputs, disc type is judged using the microprocessor (IC701).

When the laser for CDs is used, TE output from the HD layer cannot be sufficiently read. If the disc has a CD layer, sufficient TE output

can be read. In keeping, if TE output level “V” exceeds a fixed level, the judgment will be “CD layer exists.” If it does not, the judgment will
be “No CD layer exists.”

T

T

T: Short  -> HD

T: Long  -> CD

PI

FD

PI