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– 37 –

T

2

1

µ

AD IC Output

+ Side

- Side

5 V

Amplitude
from 0 to 5 V

1
2

µ

+ SIDE

+ FETOUT

- SIDE

Waveforms before low-pass filters at both
ends of the speaker.
H-bridge may be considered as BTL.
However, here and at the gate drive, dead
time is not observed; since bootstrap
operates based on output, DEAD TIME
part is in floating condition. The waveform
on the HIGH side shows that only the
booted voltage lowers.

11
12

µ

AD IC NF IN

In partial pressure OUT, 4 to 7 V amplitude
of GND reference is observed.
In IC of 75 kohms, the reference is 2.5 V
because of VREF. Due to imaginary GND
of operational amplifier inside IC, the
waveform cannot be monitored.
This waveform is partial pressure OUT.

3

4

LEVEL SHIFT OUT

DEAD TIME

ZOOM UP

Dead time is generated by level
shift input.
Leading edge is delayed at CR,
passing R at DI.
Set value: 20 - 25 nsec.

5
6

– 38 –

HOW TO USE

CAUTION

Cleaning fluid

Cleaner disc

Using the brush in the cleaner cap, apply 1 or 2 drops of the cleaning fluid to the 

brush on the CD cleaner disc which has the mark next to it.

Place the CD cleaner disc onto the CD disc tray with the brush side down, then 

press the play button.

You will hear music for about 20 seconds and the CD player will automatically stop. 

If it continuous to turn, press the stop button.

1.

2.

3.

The CD lens cleaner should be effective for 30-50 operations, however if the 

brushes become worn out earlier then please the cleaner disc.

If the CD cleaner brushes become very wet then wipe off any excess fluid with a soft 

cloth.

Do not drink the cleaner fluid or allow it to come in contact with the eyes. In the 

event of this happening then drink and / or rinse with clean water and seek medical 

advice.

The CD cleaner disc must not be used on car CD players or on computer CD-ROM 

drives.

All rights reserved. Unauthorized duplicating, broadcasting and renting this product 

is prohibited by law.

Parts code

1.

CD optical pickup Lens cleaner disc

UDSKA0004AFZZ

When the CD section does not operate when the objective lens of the optical pickup is dirty, this section may not operate. Clean
the objective lens, and check the playback operation. When this section does not operate even after the above step is taken, check
the following items.
Remove the cabinet and follow the trouble shooting instructions.
"Track skipping and/or no TOC (Table Of Contents) may be caused by build up of dust other foreign matter on the laser pickup
lens. Before attempting any adjustment make certain that the lens is clean. If not, clean it as mentioned below."

Turn the power off.
Gently clean the lens with a lens cleaning tissue and a small amount of isopropyl alcohol.
Do not touch the lens with the bare hand.

(1) Check the power to IC1 (LC78646E), the presence of the clock signal (16.9344 MHz) and the status of the RESET terminal
     (pin 66 on IC1).
(2) Does the pickup move to the PICKUP-IN Switch (SW4) position?

If (1) and (2)  are OK, check the system microcomputer (especially the communication line with the DSP).

(1) Focus-HF system check
(2) Tracking system check
(3) Spin system check
(4) PLL system check
(5) Others

– 39 –

µ

FDO

DRF

TE

Stopped

µ

FDO

TDO

Stopped

µ

If the level is not normal.

1. Is focus servo activated ?
    (Waveform drawing Figure 39-2)

Pins 7~11, 79 and 80 on IC1
Check the laser diode driver Q1 peripheral circuit.

When a disc is loaded, start playback operation.

2. Does DRF change from "L" to "H" ?

Is the disc rotating ?

3. Is the HF waveform normal ?
    (Waveform drawing Figure 39-3)

Check the spin system.

If the disc is spinning and a HF waveform is generated,
DRF will go H.

Check the laser diode driver Q1 peripheral circuit.

1. Does the pickup move to the PICKUP-IN Switch (SW4)

position ?

Sled motor (M801).

Press the OPEN/CLOSE switch (SW771) without inserting a
disc, and try starting the playback operation.

2. Does the focus (lens) move up and down ?
    (Waveform drawing Figure 39-1)

Check the focus peripheral circuit.

3. Is the laser lit ?

Spindle motor (M802).

4. Is the turntable rotating ?

Yes

Yes

Yes

No

No

No

No

No

No

No

Yes

Yes

No

– 40 –

FDO

SPDO

Stopped

µ

TE

DRF

Stopped

µ

The tracking servo is not activated.
Check the peripheral circuits at pins 14, 15 and 20 on IC1, and
CNS1A/B.

If the waveform shown in Figure 40-1 appears and soon after
NO DISC appears ?

A normal jump operation cannot be completed or the beginning of
the track cannot be found.
Check the around pin 20 on IC1.

"Initialization" is possible, but play is not possible ?

Data cannot be read. Check the VCO-PLL system.

"Initialization" is not possible.

Press the OPEN/CLOSE switch without inserting a disc, and
then try starting the play operation.

The spin driver circuit is OK.

1. The turntable rotates a little ?
    (Waveform drawing Figure 40-2)

Check around pin 22 on IC1, pins 15 and 16 on IC2, and CNS3A/B.

2. The turntable doesn't rotate.

No

Yes

No

Yes

Yes

No