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9

2

Set the holder panel 

      assembly to eject.

4

mechanism deck 

     (MB-23MK2-101)

lock plate assembly

3

two screws (M1.4 

×

 3.0)

note : When attaching the mechanism deck,
          set the mechanism deck to stop and
          adjust the position of shaft-A and part
          

A

 of the lock plate assembly.

 

shaft-A

A

1

Remove the soldering.

4

holder panel assembly

1

While pressing the button (eject), insert

      the two claws of the holder panel assembly
      into the holes indicated by arrows 

A

.

2

Move the battery coil spring in the direction

      of the arrow and secure it with the screw.

3

two screws (M1.4 

×

 1.6)

A

A

claw

claw

10

1. Clean the following parts with a denatured-alcohol-moistened

swab :

playback head

rubber belts

capstan

idlers

pinch roller

2. Demagnetize the playback head with a head demagnetizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. The adjustments should be performed with the rated power

supply voltage (3V) unless otherwise noted.

2.06 – 3.72 mN•m

FWD

21 – 38 g•cm

CQ-102C

(0.30 – 0.52 oz•inch)

0.05 – 0.29 mN•m

FWD

0.5 – 3 g•cm

Back Tension

(0.01 – 0.04 oz•inch)

2.06 – 3.72 mN•m

REV

21 – 38 g•cm

CQ-102RC

(0.30 – 0.52 oz•inch)

REV

0.05 – 0.29 mN•m

0.5 – 3 g•cm

Back Tension

(0.01 – 0.04 oz•inch)

FF

CQ-201B

more than 60 g•cm

REW

(more than 0.84 oz•inch)

1. Power supply voltage : 3V

Switch position
TAPE SPEED Switch : 4.8 cm

1. Play back WS-48A (tape center portion) in FWD mode.

Adjust the RV601 so that the frequency counter reads 2,980

±

30 Hz.

2. Play back WS-48A (tape center portion) in REV mode.

Confirm that the reading of frequency counter is within 2.5 %
from the reading in step 1.

WS-48A

3 kHz, 0 db

Tape Speed Adjustment

J102

set

18 

Ω

test
WS-48A
(3 kHz, 0 dB)

frequency 
counter

FF

CQ-403A

more than 40 g

(more than 1.42 oz)

REW

CQ-403R

11

Switch position
TAPE SPEED Switch : 2.4 cm

1. Play back WS-48A (tape center portion) in FWD mode.

Adjust the RV602 so that the frequency counter reads 1,490

±

15 Hz.

2. Play back WS-48A (tape center portion) in REV mode.

Confirm that the reading of frequency counter is within 2.5 %
from the reading in step 1.

AUDIO BOARD    (SIDE B)

RV601

(TAPE SPEED 4.8cm ADJ.)

RV602

(TAPE SPEED 2.4cm ADJ.)

J102

set

18 

Ω

test
WS-48A
(3 kHz, 0 dB)

frequency 
counter

12

•

•

All capacitors are in 

µ

F unless otherwise noted. (p: pF)

50 WV or less are not indicated except for electrolytics
and tantalums.

•

All resistors are in 

Ω

 and 

1

/

4

 

W or less unless otherwise

specified.

•

2

: nonflammable resistor.

•

C

: panel designation.

•

H

: adjustment for repair.

•

A

: B+ Line.

•

Total current is measured with no cassette installed.

•

Power voltage is dc 3V and fed with regulated dc power
supply from battery terminal.

•

Voltages are taken with a VOM (Input impedance 10 M

Ω

).

Voltage variations may be noted due to normal production
tolerances.

•

Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal production
tolerances.
No mark : PB (LISTEN)
(

) : REC (DICT)

•

Circled numbers refer to waveforms.

•

Signal path.

E

: PB (LISTEN)

a

: REC (DICT)

•

X

: parts extracted from the component side.

•

Y

: parts extracted from the conductor side.

•

: Pattern from the side which enables seeing.

Caution:
Pattern face side: Parts on the pattern face side seen from
(Side A)

the pattern face are indicated.

Parts face side:

Parts on the parts face side seen from

(Side B)

the parts face are indicated.

Note: The components identified by mark 

0

 or dotted

line with mark 

0

 are critical for safety.

Replace only with part number specified.