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– 13 –

1.

CD Block basically constructed to operated without adjustment.
Therefore, check eaech item in order given.

2.

Use YEDS-18 disc (Part No.: 3-702-101-01) unless otherwise indi-
cated.

3.

Use the oscilloscope with more than 10 M

Ω

 impedance.

4.

Clean an object lens by an applicator with neutral detergent when the
signal level is low than specified value with the following checks.

Procedure:
1. Connect the oscilloscope to TP (FEO) and TP (VC) on BD

board.

2. Connect the TP (FOK) and TP (GND) with 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. Confirm that the oscilloscope waveform (S-curve) is symmetri-

cal between 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 that the ratio of A : B

or B : A is more than 10 : 7.

• Take sweep time as long as possible and light up the brightness to

obtain best waveform.

1. How to Enter AGING Mode

1) Insert a disc into the CD player.

(Multiple discs can be inserted *1)

2) With the set turned on, press 

[     ]

 button, 

[CD3]

 button,

and 

[   ]

 (CD2) button simultaneously, and the AGING mode

is set.

(*1): The AGING mode is active only to the trays where discs

exist.

2. How to Exit from AGING Mode

Turn off  the Power, and normal operation becomes ready.

3. Operation sequence in AGING Mode

An example of operation sequence where discs exist at CD1
and CD3 is shown below.
1) Tray 1 open/close
2) Tray 3 open/close
3) CD1 TOC read
4) CD1 last track search
5) CD3 TOC read
6) CD3 last track search
Hence, 1) – 6) are repeated.

§

fl

+
–

BD board

TP (FEO)

TP (VC)

oscilloscope

A

B

symmetry

within 2.4 

±

 0.7 Vp-p

– 14 –

Procedure:
1. Connect the oscilloscope to TP (RF) and TP (VC) on BD board.
2. Turned power switch on.
3. Put disc (YEDS-18) in and press the 

[     ]

 button.

4. Confirm that oscilloscope waveform is clear and check RF sig-

nal level is correct or not.

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

Procedure:
1. Solder a lead wire to the TP301 (ADJ) on the MAIN board.
2. Connect the oscilloscope to TP (TEO) and TP (VC) on BD

board.

3. Turned power switch on.
4. Connect the lead wire connected in1, to the ground.
5. Put disc (YEDS-18) in and press the 

[     ]

 button.

6. Press the 

[DISPLAY]

 button. (Tracking servo and sled servo

are turned off.)

7. Confirm that the oscilloscope waveform is symmetrical on the

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

8. Release the lead wire.

+
–

BD board

TP (RF)

TP (VC)

oscilloscope

fl

VOLT/DIV: 200 mV
TIME/DIV: 500 ns
(with the 10 : 1 probe 
in use)

1.2 

±

 0.2 Vp-p

RF signal waveform

+
–

BD board

TP (TEO)

TP (VC)

oscilloscope

(DC range)

fl

[BD  BOARD]  – Side  B –

[MAIN  BOARD]  – Conductor Side –

TP (GND)

TP (VC)

TP (TEO)

FEO

IC103

IC101

TP

(FOK)

TP (RF)

IC102

IC301

TP301
(ADJ)

– 15 –

DISC DETECTION (A)  board

MID SENS board

DISC DETECTION (B)  board

PANEL board

LED board

OPEN/CLOSE
SW board

BD board

TRAY MOTOR board

MAIN board

U/D MOTOR board

IN SW board

MID SW board

JACK board

COUNT SW board