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– 5 –

1

Rear Cabinet

1. Screw ................. (A1) x10

5-1

2. Socket .................. (A2) x2

5-2

2

Top Cabinet

1. Knob ..................... (B1) x1

5-2

(with CD Mechanism/ 2. Screw ................... (B2) x3
Tape Mechanism/

3. Socket .................. (B3) x2

Main PWB)

3

Main PWB/

1. Screw ................... (C1) x8

5-3

Switch PWB

2. Socket .................. (C2) x4

5-3,6-2

4

Tuner Display PWB/ 1. Screw ..................  (D1) x3

6-1

Switch PWB

5

Tape Mechanism

1. Screw ................... (E1) x4

6-2

6

CD Mechanism

1. Screw ................... (F1) x3

6-2

7

Terminal PWB

1. Screw ................... (G1) x5

6-3

2. Hook ..................... (G2) x1

8

Battery PWB

1. Hook ..................... (H1) x2

6-4

Caution on Disassembly
Follow the below-mentioned notes when disassembling the
unit and reassembling it, to keep it safe and ensure excellent
performance:
1. Take cassette tape and compact disc out of the unit.
2. Be sure to remove the power supply plug from the wall

outlet before starting to disassemble the unit.

3. Take off nylon bands or wire holders where they need be

removed when disassembling the unit. After servicing the
unit, be sure to rearrange the leads where they were
before disassembling.

4. Take suffcient care on static electricity of integrated

circuits and other circuits when servicing.

(A1)x3
ø3x12mm

(A1)x1
ø3x12mm

(A1)x6
ø3x20mm

Rear Cabinet

Front Cabinet

(B2)x3
ø3x10mm

(A2)x1

(A2)x1

(B3)x1

Front Cabinet

Top Cabinet

(B1)x1

Main PWB

Headphones
PWB

(C1)x6
ø3x10mm

(C1)x2
ø3x10mm

(C2)x1

Switch PWB

Main PWB

Top Cabinet

– 6 –

Perform steps 1, 2, 3 and 6 of the disassembly method to
remove the CD mechanism.

1. Remove the screws (A1) x 2 pcs., to remove the shaft (A2)

x1 pc.

2. Remove the stop washer (A3) x1 pc., to remove the gear

(A4) x 1 pc.

3. Remove the pickup.

(D1)x2
ø3x12mm

(D1)x1
ø3x10mm

Front Cabinet

Switch PWB

Tuner Display
PWB

Top Cabinet

Tape
Mechanism

CD Mechanism

(F1)x3
ø2.5x10mm

(E1)x4
ø3x10mm

(C2)x2

(C2)x1

(G1)x2
ø3x10mm

(G1)x1
ø3x10mm

(G1)x2
ø3x10mm

Terminal PWB

Driver

Push

(G2)x1

Rear Cabinet

Rear Cabinet

(H1)x1

(H1)x1

Battery PWB

Pull

Pull

(A1) x2
   2.6 x6mm

Stop 
Washer
(A3) x1

CD 
Mechanism

Gear
(A4) x1

Shaft
(A2) x1

Pickup

– 7 –

PLAY: TW-2412

Over 120 g

Play: TW-2111

25 to 65 g.cm

Fast Forward: TW-2231

60 to 130 g.cm

Rewind: TW-2231

60 to 130 g.cm

MTT-111 In motor

3,000 

±

 90 Hz

Output: Speaker
Teaminal
(CNP201 Load
resistance: 8 ohms)

Volume control

Max

Function switch

Tape/Power Off

X-BASS

On

MTT-118

1.8 V 

±

 3 dB

Speaker Terminal
(Load resistance: 8 ohms)

MTT-114

Output: Speaker Terminal
(CNP201 Load resistance: 8 ohms)

L301

82 kHz 

±

 6 kHz

Pin 2 of CNP201

– 6 kHz

fL: Low-range frequency
fH: High-renge frequency

IF

450 kHz

1,620 kHz

T3

*1

 Band

—

522 kHz

(fL): L4

*3

Coverage

1.0 

±

 0.1 V

Tracking

600 kHz

600 kHz

(fL): L3

*2

1,400 kHz

1,400 kHz

(fH):TC1

•  FM RF
Signal generator: 1 kHz, 75 kHz dev., FM modulated

Band

—

87.50 MHz

(fL): L2

*1

Coverage

3.4 

±

 0.1 V

RF

98.00 MHz

98.00 MHz

L1

*2

(10~30 dB)

*1. Input: Antenna,

Output: TP1

*2. Input: Antenna,

Output: Speaker Terminal

•  Detection
Signal generator: 10.7 MHz, FM sweep generator

IF

10.7 MHz

98.00 MHz

T1(Turn

Input: Pin 1 of

the core of

IC1

T1 fully

Output: TP2

counter-
clockwise.

•  AM IF/RF
Signal generator: 400 Hz, 30%, AM modulated

*1. Input: Antenna,

Output: Pin19 of IC2

*2. Input: Antenna,

Output: Speaker Terminal

*3. Input: Input is not connected,

Output: TP1

VR1

76 kHz 

±

 200 Hz

Pin 13, pin 21 and
ground of IC2

Note:
After preparing the test circuit shown in Fig. 7-1, connect the
Pin 13, Pin 21 and ground of the IC2 with the test circuit, and
measure the value. At  this time, apply a standard unmodulated
signal input and adjust the VCO.

Pin 13 of IC2

Pin 21 of IC2

D

G

S

10 kohm

TO FREQUENCY
        COUNTER

FET : 2SK19 or 2SK54

1

1

VCO

VR1

IC2

T3

L4

L2

IC1

L1

FM IF

T1

TC1

AM TRACKING

L3

AM BAR

ANTENNA

FM ROD ANTENNA

FM BAND

COVERAGE

T2

AM IF

TP2

FM RF

FM DET.

TP1

13

17

19

21

R26

R7

AM BAND

COVERAGE

MAIN PWB

fL

fH

– 8 –

Since this CD system incorporates the following automatic
adjustment function, when the pickup is replaced, it is necessary
to reajust it.
Since this CD unit does not need adjustment, the combination
of PWB and laser pickup unit is not restricted.

While holding down the "STOP" button, move the FUNCTION/POWER switch to "CD".
Then, release the "STOP" button and, within 0.5 second, connect the TEST POINT to GND (within 0.5 second).
(See Fig. 8)

Start

Note

1. When the CD LID switch is in the OFF position, the unit will be able to enter the test mode.

However, playback cannot be performed in this mode.

2. You can only move the pickup.
3. The LCD display should be the same as it is for normal CD operations.

1

2

When the "PLAY" button is pressed, the laser will be lit, and when the "STOP" button is pressed, it will be
turned off. Playback will also start and stop when these buttons are pressed.

Turning the tracking servo on or off.

3

a. If the "PLAY" button is pressed while in the stop mode, the laser will simply be turned on at first.
b. If the laser is lit and the "PLAY" button is pressed again, playback will start from the current pickup position.
c. If the "STOP" button is pressed, playback will stop. When pressed again, the laser will be turned off.

a. Each time the PAUSE button is pressed during playback, the tracking servo will be turned on or off.
(Note: If the PLAY button is pressed while in the stop mode, the tracking servo will automatically be
turned on.)

Operation

The use of the "UP/CUE" button will move the pickup to the outermost position.
The use of the "DOWN/REVIEW" button will move the pickup to the innermost position.

While holding down the "STOP" button, move the FUNCTION/POWER switch to "CD".
Then, release the "STOP" button and, within 0.5 second, press the REVIEW/DOWN button.

Start

Display

1

2

3

* After the number 

3

 has appeared in the display, each time the "UP/CUE" button is pressed, the display will switch

in the following order: 

1

, 

2

, and then 

3

.

1 second

1 second

SW774

TRACK DOWN/

REVIEW

R771

3.9K

TEST

POINT

R772

2.7K

R773

1.8K

R774

1.5K

R776

10K

SW773

TRACK UP/

CUE

SW771

PLAY

SW7712

STOP

TO CD SECTION

+B

3

1

SWITCH PWB – A2