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— 9 —

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

swab :

record/playback heads

pinch rollers

erase head

rubber belts

capstan

idlers

2. Demagnetize the record/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 sup-

ply voltage unless otherwise noted.

FWD

FWD
back tension

REV

REV
back tension

FWD tension

REV tension

FF/REW

Torque meter

Meter reading

36 to 61g • cm

(0.5–0.84 oz • inch)

2 to 6g • cm

(0.02–0.08 oz • inch)

36 to 61g • cm

(0.5–0.84 oz • inch)

2 to 6g • cm

(0.02–0.08 oz • inch)

61 to 143g • cm

(0.85–1.99 oz • inch)

100g or more

(3.53 oz or more)

100g or more

(3.53 oz or more)

1. Demagnetize the record/playback head with a head damagnetizer.
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the

parts adjusted.

4. The adjustmetns should be performed with the rated power sup-

ply voltage unless otherwise noted.

5. The adjustments should be performed in the order given in this

service manual. (As a general rule, playback circuit adjustment
should be completed before performing recording circuit
adjustment.)

6. The adjustments should be performed for both L-CH and R-ch.
7. Switches and controls should be set as follows unless otherwise

specified.

Signal

10 kHz, –10 dB

3 kHz, 0 dB

315 Hz, 0 dB

Used for

Azimuth Adjustment

Tape Speed Adjustment

Level Adjustment

 Perform this adjustments for both decks.

Procedure :
1. Mode : Playback (FWD)

+

set

test tape
P-4-A100
(10kHz, –10dB)

main board
CN403
Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

level meter

main board
CN403
Pin 

2

Torque

CQ-102C

CQ-102C

CQ-102RC

CQ-102RC

CQ-201B

CQ-403A

CQ-403R

Tape

P-4-A100

WS-48B

P-4-L300

— 10 —

2. Turn the adjustment screw and check output peaks. If the peaks

do not match for L-CH and R-CH, turn the adjustment screw so
that outputs match within 1 dB of peak.

3. Mode : Playback (FWD)

test tape
P-4-A100
(10kHz, –10dB)

main board
CN403
Pin 

3

4. Repeat steps 1 to 3 in playback (REV) mode.
5. After the adjustments, apply suitable locking compound to the

parts adjusted.

Adjustment Location : Record/Playback Head (Deck A and B)

L-CH
peak

screw
position

R-CH
peak

within
1dB

output
level

R-CH
peak

L-CH
peak

within 1dB

screw
position

FWD side

REV side

Adjustment screw

Start the tape speed adjustment as bellow after setting the
test mode. The tape speed can be changed with the HIGH
SPEED DUBBING button during the test mode.

Method :
1. Turn the power switch on.
2. Press the DISPLAY/DEMO button, MENU 1 button and TUNER/

BAND button simulateously.

Procedure :
Mode : Playback (FWD)

main board
CN403 (Pin 

3

 : L-CH)

(Pin 

1

 : R-CH)

frequency counter

test tape
WS-48B
(3kHz, 0dB)

level meter

set

test tape
P-4-L300
(315Hz, 0dB)

main board
CN403 (Pin 

3

 : L-CH)

(Pin 

1

 : R-CH)

Deck A is RV311 (L-CH) and RV411 (R-CH), deck B is RV301 (L-
CH) and RV401 (R-CH) so that adjustment within the following
adjustment level.

CN403 PB level : 301.5 to 338.3 mV (–8.2 to –7.2 dB)
level difference between the channels : within 

±

 0.5 dB

Adjustment Location : MD board

1. Insert tha WS-48B into the deck A to playback.
2. Press the HIGH SPEED DUBBING button. Then at HIGH

SPEED mode.

3. Adjust RV652 on the MD board so that the frequency counter

reading becomes 6,000 

±

 30 Hz.

4. Press the HIGH SPEED DUBBING button again to be set the

NORMAL SPEED mode.

5. Set to the playback mode.
6. Adjust RV651 on the MD board so that the frequency counter

reading becomes 3,000 

±

 15 Hz.

Frequency difference between deck A and deck B the beginning of
the tape should be within 

±

 1.5%.

Adjustment Location : MD board

Mode : Playback (FWD)

Pin 

2

L

R

Pin 

1

oscilloscope

set

Waveform of oscilloscope

good

wrong

in phase

45

°

90

°

135

°

180

°

set

— 11 —

VIDEO IN
1) 315Hz
2) 10kHz

50mV (–23.8dB)

blank tape
CS-123

AF OSC

attenuator

600

Ω

set

2. Mode : Playback

recorded
position

set

Confirm playback the signal recorded in step 1 become adjustment
level as follows.
If these levels do not adjustment level, adjust the RV341 (L-CH) and
RV441 (R-CH) on the MD board to repeat step 1 and 2.

Adjustment level : The playback output of 10 kHz level difference

against 315Hz reference should be 

±

 0.5 dB

Adjustment Location : MD board

Procedure :
1. Mode : record

VIDEO IN
315Hz, 50mV (–23.8dB)

AF OSC

attenuator

600

Ω

blank tape
CS-123

recorded
position

set

Confirm playback the signal recorded in step 1 become adjustment
level as follows.
If these levels do not adjustment level, adjust the RV301 (L-CH) and
RV351 (R-CH) on the main board to repeat steps 1 and 2.

Adjustment level: CN 403 PB level: 47.2 to 53.0 mV

(–24.3 to –23.3 dB)

Adjustment Location : main board

[MAIN BOARD] (Component Side)

Procedure :
1. Mode : record

2. Mode : Playback

level meter

CN 403 (Pin 

3

 : L-CH)

(Pin 

1

 : R-CH)

set

level meter

main board
CN403 (Pin 

3

 : L-CH)

(Pin 

1

 : R-CH)

RV351 REC LEVEL (R-CH)

1

3

CN403

RV301 REC LEVEL
(L-CH)

– DECK B –

RECORD

BIAS

L

RV441 RV341

(NORMAL)

RV651

¬

R

TAPE SPEED

(HIGH)

RV652

¬

PB

LEVEL

L 

¬

R 

¬

– DECK A –

[MD BOARD] (Conductor Side)

PB LEVEL

RV301

¬

L

RV401

¬

R

— 12 —

Adjustment Location
EA, JE model
[TCB BOARD] (Component Side)

Other model
[TCB BOARD] (Component Side)

µ

 As a front-end (FE1) is difficult to repair if faulty, replace it

with new one.

FM Tuned Level adjustment should be performed after this
AM Tuned Level Adjustment.

• Abbreviation

EA

: Saudi Arabia model

JE

: Tourist model

loop antenna

RV41

IC41

RV42

RV42
FM Tuned Level

AM antenna
terminal (TM1)

FE1

TM1

75 

Ω

 coaxial

set

Carrier frequency: 98MHz
Modulation:

AUDIO 1kHz, 75kHz
deviation (100%)

Output level:

25dB (at 75

Ω

 open)

Band: AM or MW
Procedure:
1. Set the output of SSG so that the input level of the set becomes 55

dB.

2. Tune the set to 999 kHz or 1,050 kHz.
3. Adjust RV41 (EA, JE model), RV42 (Other model) to the point

(moment) when the TUNED  indicator will change from going
off to going on.

Adjustment Location: TCB board

 This adjustment should be performed after the AM Tuned Level

Adjustment.

RV41
FM Tuned Level

IC2

RV41

RV42
AM Tuned Level

FE1

TM1

Band: FM
Procedure:
1. Supply a 25 dB 98 MHz signal from the ANTENNA terminal.
2. Tune the set to 98 MHz.
3. Adjust RV42 (EA, JE model), RV41 (Other model) to the point

(moment) when the TUNED indicator will change from going off
to going on.

60cm

AM RF SSG

30% amplitude
modulation by
400Hz signal

Modulation: 999 kHz (at 9 kHz step)

1,050 kHz (at 10 kHz step)

Field strength dB (

µ

V/m) = SSG output level dB (

µ

V/m) –26dB.

loop antenna
(Supplied accessories)

set

RV41
AM Tuned Level

RV42

FM RF stereo signal
generator

FM ANTENNA terminal
(TM1)