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– 21 –

  1. Tuner

(  ): AM mode
Marking except for (  ): FM mode

2. CD

(  ): Play mode
Marking except for (  ): Stop state

3. Deck section

(  ): Record mode
Marking except for (  ): Playback mode
Display / Control section:
(  ): Active state
Marking except for (  ): CD Function mode at stop state

• Schematic diagram and Wiring Side of P.W.Board for this

model are subject to change for improvement without prior
notice.

• Parts marked with “      ” (

          ) are important for

maintaining   the safety of the set. Be sure to replace these
parts with specified ones for maintaining the safety and
performance of the set.

• Resistor:

To differentiate the units of resistors, the symbol as K and M
are used: the symbol K means 1000 ohm and the symbol M
means 1000 kohm and the resistor without any symbol is an
ohm resistor. The resistor designated "Fusible" is a fuse type
resistor

• Capacitor:

To indicate the unit of capacitor, a symbol P is used: this
symbol P means micro-micro-farad and the unit of the capacitor
without such a symbol is microfarad. As to electrolytic capacitor,
the expression “capacitance/withstand voltage” is used.
(CH), (TH), (RH), (UJ): Temperature compensation
(ML): Mylar type
(P.P.): Polypropylene type

• The indicated voltage in each section is the one measured by

Digital Multimeter between such a section and the chassis
with no signal given.

SW102

RECODE/PLAYBACK

OFF—ON

SW201

FUNCTION/POWER

TAPE—TUNER— CD/
OFF—ON

SW202

SURROUND (132H ONLY)

OFF—ON

SW203

X-BASS

OFF—ON

SW501

BAND

OFF—ON

SW502

TUNER DOWN

OFF—ON

SW503

TUNER UP

OFF—ON

SW504

MEMORY

OFF—ON

SW505

PRESET UP

OFF—ON

SW506

PRESET DOWN

OFF—ON

SW601

TAPE MAIN

OFF—ON

SW702

PICKUP IN

OFF—ON

SW761

CD LID OPEN/CLOSE

OFF—ON

SW771

PLAY/REPEAT

OFF—ON

SW772

STOP

OFF—ON

SW773

TRACK UP/CUE

OFF—ON

SW774

TRACK DOWN/REVIEW

OFF—ON

E C B

(S) (G) (D)

(1) (2) (3)

FRONT

VIEW

2SA673-C
2SC1815 GR
2SC1674 K

E C B

FRONT

VIEW

S8050D

E B C

FRONT

VIEW

S9012H

– 22 –

3

5ms
0.50 V
IC801  20   F.E

1

5ms
5.0 V
IC801  54   DRF

STOP

PLAY

FOCUS

SERCH

0.5ms
1.00 V
  HF

0.5ms
5.0 V
 HFL

0.5ms
5.0 V
 TES

1

2

3

CUE

0.5ms
1.00 V
  H.F

1

2

3

0.5ms
5.0 V
 HFL

0.5ms
5.0 V
TES

REVIEW

0.5ms
10.0 V
  JP+

0.5ms
10.0 V
  JP-

0.5ms
0.50 V
  JP

0.5ms
1.00 V
  TE

50ms
10.0 V
  JP+

CUE

50ms
10.0 V
  JP-

50ms
0.50 V
  JP

50ms
1.00 V
  TE

REVIEW

50ms
10.0 V
  JP+

50ms
10.0 V
  JP-

50ms
0.50 V
  JP

50ms
1.00 V
  TE

0.5ms
10.0 V
  JP+

0.5ms
10.0 V
  JP-

0.5ms
0.50 V
  JP

0.5ms
1.00 V
  TE

PLAY

20ms
1.00 V
  SPO

NORMAL DISC
TN0=01

20ms
2.00 V
CLV+

PLAY

TCD-712 (140mm)
TN0=01

50ms
1.00 V
  SPO

50ms
2.00 V
CLV+

PLAY

TCD-712

5s
100mV
  SLD

1

0.5s
100mV
  SLD

1

– 23 –

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 troubleshooting 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.

See if the pick-up is in the pick-up in SW702 position.

If the items mentioned above are OK, check the main
microcomputer IC701.

Yes

Yes

The CD operating keys don't work.

Check the CD, DPS microcomputer (IC701), power supply, 4.19
MHz and 16.93 MHz clock, and reset terminal.

Check the waveform of SCK, SO (DATA) and SI (COMM).

Yes

Yes

Playback can be performed without a disc.

Yes

Does the output waveform of IC801(16)(FD) match that shown in
Fig. 23?

Check the area around IC804-BI801/CNS801.

Yes

Check the IC801(50)(CLK) line, 4MHz.
Check the microcomputer data on pins (51)(CL), (52)(DAT) and
(53)CE.

No

Yes

No

Does the pick-up move up and down twice?

Focus search OK.

Focus search
is performed
two times
when play
operation is
done without
disc.

  0.5s
0.50 V
IC801  16  FD

2

1

  0.5s
0.50 V
IC801  15  TD

Check the Focus - HF system.

– 24 –

Check the laser diode driver.

Does the DRF signal change from "L" to "H"?

No

If the disc is not turning, the DRF
should not change to "H".

Is HF waveform normal (see the Fig. 24-1, 2)?

Yes

Is the Focus servo active? (Can you hear it working?)

No

Check the area around IC801(16) - (21) (focus servo circuit).

evel is abnormal.

Check the periphery
of IC801 pins 41 and
42.

No

Waveform is unstable.

Check the spin
system.

Yes

Yes

Yes

Yes

Yes

Check the spin
system.

HF
0.1V/DIV
0.5µsec/DIV(DC)
(When playing
 back the disc)

Waveform in case
of normal play-
back

3

2
1

4

  0.5s
1.00 V
IC801  16  FD

  0.5s
10.0 V
IC801  12  CLV+

  0.5s
10.0 V
IC801  54  DRF

  0.5s
2.00 V
IC801   7   TE

Check the tracking system.

▼

▼

▼

Check waveform of IC801 pin 7 (TE).

Check the periphery of IC801
pin 8 to pin 15, and IC804 to
BI801/CNS801.

Tracking servo is inoperative.

The waveform shown in Fig. 24-3
appears, and no-disc state appears
soon.

Yes

Yes

Yes

Yes

Play is possible in
TEST mode.

Although IL is possible,
play is impossible.

Normal jump is impeded, and the
program top cannot be reached.

Check the periphery of
IC801 pin 14.

Yes

Data  cannot be read.

Check the VCO-PLL system.

Yes

3

4

  5ms
1.00 V
IC801   7   TE

  5 ms
5.0 V
IC801  54  DRF