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– 13 –

1. Remove the screws (B1) x 2 pcs., to remove the shaft (B2).
2. Remove the stop washer (B3) x 1 pc., to remove the gear

(B4).

3. Remove the pickup.

Perform steps 1, 2, 3, 9 and 12 of the disassembly method to
remove the CD mechanism.

1. Bend the hooks (A1) x 5 pcs., to remove the loading motor.

Note
After removing the connector for the optical pickup from the
connector, wrap the conductive aluminium foil around the
front end of connector to protect the optical pickup from
electrostatic damage.

(A1)x2

(A1)x1

Loading Motor

Slide Chassis

(A1)x2

(B1) x2
  ø2.6 x6mm

Shaft
(B2) x1

Stop Washer
(B3) x1

Gear
(B4) x1

CD Mechanism

Pickup

•

Play: TW-2111

Tape 1: Over 80 g
Tape 2: Over 80 g

•

Play: TW-2111

30 to 80 g.cm

30 to 80 g.cm

Fast forward: TW-2231

—

70 to 180 g.cm

Rewind: TW-2231

—

70 to 180 g.cm

Normal

MTT-111

Variable

3,000 

±

Speaker

speed

Resistor in

30 Hz

terminal

motor.

(Load
resistance:
6 ohms)

•

TAPE MECHANISM

Motor

Variable Resistor
in motor

– 14 –

• 

Signal generator: 400 Hz, 30%, AM modulated

*1. Input: Antenna

Output: TP302

*2. Input: Antenna

Output: TP301

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

AM IF

450 kHz

1,620 kHz

T351

*1

AM Band

—

522 kHz

(fL): T306

*2

Coverage

1.1 

±

 0.1 V

AM Tracking 990 kHz

990 kHz

(fL): T303

*1

T306

T303

R357

TP301

TP302

T351

AM IF

AM
TRACKING fL

AM BAND
COVERAGE fL

FE301

SO301
FM ANTENNA
TERMINAL

CNP302
AM LOOP
ANTENNA

MAIN PWB

1

R381

[Servo System Error]

0001

Cannot detect Pickup-in SW

0002

DSP access error

[Error during close operation]

0101

Open/Close SW Low 

→ 

High not functioning

0103

Open/Close SW High 

→

 Low not functioning

[Error during open operation]

0201

Open/Close SW Low 

→ 

High not functioning

0203

Open/Close SW High 

→

 Low not functioning

[Error during skip operation]

0302

Pickup-in SW is not detected

0306

During Disc 1 search, Open/Close SW or Clamp SW
or Disc SW do not change to low.

0307

Clamp SW Low 

→ 

High not functioning

0308

Clamp SW High 

→

 Low not functioning

Since this CD system incorporates the following automatic
adjustment functions, readjustment is not needed when
replacing the pickup. Therefore, different PWBs and pickups
can be combined freely.
Each time a disc is changed, these adjustments are
performed automatically. Therefore, playback of each disc
can be performed under optimum conditions.

(1) Offset adjustment (The offset voltage between the head

amplifier output and the VREF reference voltage is
compensated inside the IC.)

  * Focus offset adjustment
  * Tracking offset adjustment

(2) Tracking balance adjustment (waveform drawing Fig.

14-2 EFBL)

(3) Gain adjustment (The gain is compensated inside the IC

so that the loop gain at the gain crossover frequency will
be 0dB.)

  * Focus gain adjustment
  * Tracking gain adjustment

•  Adjustment

EFBL

FDO

TE

Stopped

•  FM
Notes:
1: Description of the "FM IF Adjustment" is not carried on this

Manual. It is because the IF coil in the FM front end section
has been best adjusted in the factory so that its further
adjustment is not needed at the field. When replacing the
FM front end assembly, no adjustment is needed either.

2: The parts in the FM front end section are prepared in a

complete unit, so you can't obtain each part individually

– 15 –

•

 The indicated voltage in each section is the one measured

by Digital Multimeter between such a section and the chas-
sis with no signal given.
1. In the tuner section,

(  ) indicates AM
< > indicates FM stereo

2. In the main section, a tape is being played back.
3. In the deck section, a tape is being played back.

(  ) indicates the record state.

4. In the power section, a tape is being played back.
5. In the CD section, the CD is stopped.

•

 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, such 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
ohm-type resistor. Besides, the one with “Fusible” is a fuse
type.

•

 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

•

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

model are subject to change for improvement without prior
notice.

SW714

CD

ON—OFF

SW715

TAPE

ON—OFF

SW716

TUNING /TIME DOWN

ON—OFF

SW717

MEMORY/SET

ON—OFF

SW718

REWIND

ON—OFF

SW719

FAST FORWARD

ON—OFF

SW720

PLAY/REPEAT

ON—OFF

SW721

STOP

ON—OFF

SW723

REC/PAUSE

ON—OFF

SW724

TUNING/TIME UP

ON—OFF

SW725

TUNER (BAND)

ON—OFF

SW1

OPEN/CLOSE

ON—OFF

SW2

CLAMP

ON—OFF

SW3

DISC NUMBER

ON—OFF

SW4

PICKUP IN

ON—OFF

SW701

ON/STAND-BY

ON—OFF

SW702

CLOCK

ON—OFF

SW703

TIMER/SLEEP

ON—OFF

SW709

DISC SKIP

ON—OFF

SW710

OPEN/CLOSE

ON—OFF

SW711

EQUALIZER/X-BASS/DEMO

ON—OFF

SW712

VOLUME UP

ON—OFF

SW713

VOLUME DOWN

ON—OFF

(1)  (2) (3) 

(S) (G) (D) 

E   C    B 

FRONT

VIEW

2SC1845 F
2SC3331
2SC380 O
KTA1266 GR
KTA1271 Y
KTA1273 Y
KTC3203 Y
KRC102 M
KRC104 M
KRC107 M

KTC2026

4204SRT7

B C E

FRONT

VIEW

FRONT
VIEW

– 16 –

FDO

TDO

Stopped

1

IC2  24

2

IC2  23

FDO

DRF

TE

Stopped

1

IC2  24

3

IC2  72

4

IC1  18 ,

IC2  16

µ

5

IC1  27

TE

DRF

Stopped

3

IC2  72

4

IC1  18 ,

IC2  16

FDO

SPDO

Stopped

1

IC2  24

6

IC2  25

FDO

PDO2

PDO1

Stopped

1

IC2  24

7

IC2   1

8

IC2   2

DOUT

Stopped

9

IC2  37

DATA

DATACK

LRSY

Stopped

10

IC2   57

IC2  58

IC2  59

11

12

EFBL

FDO

TE

Stopped

1

IC2  24

4

IC1  18 ,

IC2  16

IC1  13 ,

IC2  22

13