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— 9 —

Procedure :
1. Connect oscilloscope to test point TP (FEO) on BD board.
2. Connect between test point TP (FOK) and Ground by lead wire.
3. Turned Power switch on.
4. Put disc (YEDS-18) in and turned Power switch on again and

actuate the focus search. (actuate the focus search when disc table
is moving in and out.)

5. Check the oscilloscope waveform (S-curve) is symmetrical be-

tween A and B. And confirm peak to peak level within 2.4 ± 0.7
Vp-p.

S-curve waveform

6. After check, remove the lead wire connected in step 2.

 • Try to measure several times to make sure than the ratio of

A : B or B : A is more than 10 : 7.

• Take sweep time as long as possible and light up the bright-

ness to obtain best waveform.

Procedure :
1. Connect oscilloscope to test point TP (RF) on BD board.
2. Turned Power switch on.
3. Put disc (YEDS-18) in and playback.
4. Confirm that oscilloscope waveform is clear and check RF signal

level is correct or not.

Clear RF signal waveform means that the shape “ ” can be
clearly distinguished at the center of the waveform.

RF signal waveform

level: 1.3 ± 0.3 Vp-p

VOLT/DIV: 200 mV
TIME/DIV: 500 nS

BD board

oscilloscope

A

B

within 2.4 ± 0.7 Vp-p

symmetry

BD board

TP (RF)
TP (VC)

oscilloscope

TP (FEO)
TP (VC)

1. CD Block is basically designed to operate without adjustment.

Therefore, check each item in order given.

2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10M  impedance.
4. Clean the object lens by an applicator with neutral detergent when

the signal level is low than specified value with the following
checks.

5. Adjust the focus bias adjustment when optical block is replaced.

BD board

TP (RF)
TP (VC)

oscilloscope

Procedure:
1. Connect oscilloscope to test point TP (RF) on BD board.
2. Turned Power switch on.
3. Put disc (YEDS-18) in and playback.
4. Adjust RV101 so that the waveform is clear.

(Clear RF signal waveform means that the shape “ ” can be clearly
distinguished at the center of the waveform.)

5. After adjustment, check the RF signal level.

• RF signal

VOLT/DIV: 200 mV
TIME/DIV: 500 nS

level: 1.3 ± 0.3 Vp-p

— 10 —

[BD BOARD] — Component Side —

Procedure:
1. Connect a lead wire to the test point TP501 on Display board.
2. Connect oscilloscpe to test point TP (TEO) on BD board.
3. Turned power switch on, load the disc (YEDS-18).
4. Connect a lead wire connected to the test point TP501 to ground.
5. Press the TIME button. (TRACKING SERVO OFF)
6. Playback the disc (YEDS-18).
7. Confirm that the oscilloscope waveform is symmetrical on the

top and bottom in relation to 0Vdc, and check this level.

Traverse waveform

oscilloscope

BD board

TP (TEO)
TP (VC)

IC104

GND

PCK

RF

RV101

IC101

FOK

RV102

TEO

FEO

TEI

FEI

VC

RV103

IC102

TP501

IC501

A

B

level: 300 ± 100 mVp-p

0V

A – B

2 (A + B)

Specified level: •                     x 100 = less than ± 7%

• A + B = 300 ± 100 mVp-p

8. Remove the lead wire connected in step 1.

This gain has a margin, so even if it is slightly off.
There is no problem.
Therfore, do not perform this adjustment.
Please note that it should be fixed to mechanical center position when
you moved and do not know original position.

[DISPLAY BOARD] — Conductor Side —

— 11 —

PANEL board

SENSOR board

MOTOR (TURN) board

DISPLAY board

MAIN board

MOTOR (SLIDE) board

BD board

CONNECTOR board

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I

I

O

O

I

I

O

O

I

O

I

–

–

I

–

O

O

I

O

O

O

O

I

–

O

O

O

O

I

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–

–

I

I

O

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1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31 to 33

34

35

36

37

38

39

40

V

DD

PWMSW

DISC SENS

TABLE R

TABLE L

JOG1

JOG0

BD PWR

BD RST

RESET

X2

X1

GND

ADJ

V

DD

CLOCK

DATA

SENS

XLT

PRGL

SOCLK

SUBQ

AV

SS

FCSSW

A MUTE

LOD OUT

LOD IN

OUT SW

KEY3 to KEY1

AV

DD

AV

REF

SCOR

TABLE SENS

BUS OUT

BUS IN

V

SS

Power supply. (+5V)

Pulse width modulation select switch for turn table. (Not used)

Slit sensor input of disc table. “L”: None , “H”: Load

Power ON/OFF control signal output to BD block. “L”: OFF , “H”: ON

Reset signal output to BD block. “L”: Reset

System reset input. “L”: Reset

Function

Pin No.

Pin Name

I/O

Table motor control signal output.

Jog dial encoder input.

Main system clolck. (5 MHz)

Ground

Not used. (Open)

Test pin. “L”: Test mode

Power supply. (+5V)

Serial clock output to digital signal processor and D/A converter.

Serial data output to digital signal processor and D/A converter.

Each mode input from digital signal processor and D/A converter.

Serial data latch pulse output to digital signal processor and D/A converter.

Serial data latch pulse output to digital filter.

Sub-code Q data read clock output to digital signal processor.

Not used. (Open)

Sub-code Q data serial input from Digital signal processor.

Ground (A/D converter)

Focus gain switching output. “L”: Normal , “H”: Down

Muting ON/OF control output. “H”: Mute (Not used)

Loading out detection signal input.

Key input (A/D)

Power supply (+5V) (A/D converter)

Reference voltage input (+5V) (A/D converter)

Sub-code sync detection input.

Table address detection sensor input.

Audio bus signal ouput.

Audio bus signal input.

Ground

Loading motor control signal output.