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– 13 –

0 dB=0.775 V

Tape

Signal

Used for

P-4-A100

10 kHz, –10 dB

Azimuth Adjustment

WS-48B

3 kHz, 0 dB

Tape Speed Adjustment

P-4-L300

315 Hz, 0 dB

Level Adjustment

1. Demagnetize the record/playback head with a head demagne-

tizer.

2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the

parts adjust.

4. The adjustments should be performed with the rated power

supply voltage unless otherwise noted.

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

this service manual.  (As a general rule, playback circuit ad-
justment 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 other-

wise specified.

• Test Tape

  Perform this adjustments for both decks

Procedure:
1. Mode:  Playback (FWD)

set

MAIN board
CN301
Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

MAIN board
CN301
Pin 

2

 (GND)

+
–

level meter

test tape
P-4-A100
(10 kHz, –10 dB)

Precaution
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 demagne-

tizer.

3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustments, apply suitable locking compound to the

parts adjusted.

5. The adjustments should be performed with the rated power

supply voltage unless otherwise noted.

Mode

Torque meter

Meter reading

FWD

CQ-102C

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

FWD

CQ-102C

2 to 6 g • cm

back tension

(0.03 – 0.08 oz • inch)

REV

CQ-102RC

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

REV

CQ-102RC

2 to 6 g • cm

back tension

(0.03 – 0.08 oz • inch)

FF/REW

CQ-201B

71 to 143 g • cm

(0.99 – 1.99 oz • inch)

FWD tension

CQ-403A

100 g or more

(3.53 oz or more)

REV tension

CQ-403R

100 g or more

(3.53 oz or more)

– 14 –

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 1dB of peak.

3. Mode:  Playback (FWD)

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

pats adjusted.

Adjustment Location: Playback Head (Deck A).

 Record/Playback/Erase Head (Deck B).

Start the Tape Speed adjustment as below after setting to the test
mode.
In the test mode, the tape speed is high during pressing the

[HI-DUB]

 button.

Procedure:
1. Turn the power switch on.
2. Press the

p button, 

[ENTER/NEXT]

 button and 

[DISC 3]

 button

simultaneously.
(The “VOLUME” on the fluorescent indicator tube will blink
while in the test mode.)
To exit from the test mode, press the

u

button.

Mode:  Playback

1. Insert the WS-48B into the deck B.
2. Press the

· button on the deck B.

3. Press the 

[HI-DUB]

 button in playback mode.

Then at HIGH speed mode.

4. Adjust RV1001 on the LEAF SW board do that frequency

counter reads 6,000 ± 180 Hz.

5. Press the 

[HI-DUB]

 button.

Then back to NORMAL speed mode.

6. Adjust RV1002 on the LEAF SW board so that frequency

counter reads 3,000 ± 90 Hz.

Adjustment Location:  LEAF SW board
Sample value of Wow and Flutter: 0.3% or less W.RMS (JIS)

(WS-48B)

Procedure:
Mode:  Playback

Deck A is RV311 (L-CH) and RV411 (R-CH), Deck B is RV301
(L-CH) and RV401 (R-CH) so that adjustment within adjustment
level as follows.
Adjustment Level:

CN301 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:  AUDIO board

Screw
position

L-CH
peak

within
1dB

Output
level

L-CH
peak

R-CH
peak

within
1dB

Screw
position

R-CH
peak

set

test tape
P-4-A100
(10 kHz, –10 dB)

(pin 

1

: R-CH)

oscilloscope

V

H

waveform of oscilloscope

in phase 45 

°

90 

°

135 

°

180 

°

good

wrong

(pin 

2

: GND)

(pin 

3

: L-CH)

MAIN board
CN301

+
–

set

test tape
WS-48B 
(3 kHz, 0 dB)

MAIN board
CN301 (Pin 

3

 : L-CH)

(Pin 

1

 : R-CH)

frequency counter

+
–

set

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

MAIN board
CN301 (Pin 

3

: L-CH)

(Pin 

1

: R-CH)

level meter

forward

reverse

– 15 –

Procedure:
INTRODUCTION
When set to the test mode performed in 

Tape Speed Adjustment

,

when the tape is rewound after recording, the “REC memory mode”
which rewinds only the recorded portion and playback is set.
This  “REC memory mode” is convenient for performing this ad-
justment. During recording, the input signal FUNCTION will au-
tomatically switch to VIDEO.
(After recording, press the  – 

0 button without stopping will

return to the position where recording was started.)

1. Press 

[FUNCTION]

 button to select VIDEO. (This step is not

necessary if the above test mode has already been set.)

2. Insert a tape into deck B.
3. After press 

[    REC]

 button, press

P button, then recording

start.

4. Mode:  Record

5. Mode:  Playback

6. Confirm playback the signal recorded in step 3 become ad-

justable level as follows.
If these levels do not adjustable level, adjustment the RV341
(L-CH) and RV441 (R-CH) on the AUDIO board to repeat
steps 4 and 5.

Adjustable level: Playback output of 315 Hz to playback output

of 10 kHz: ± 1.0 dB

Adjustment Location:  AUDIO board

Procedure:
INTRODUCTION
When set to the test mode performed in 

Tape Speed Adjustment

,

when the tape is rewound after recording, the “REC memory mode”
which rewinds only the recorded portion and playback is set.
This  “REC memory mode” is convenient for performing this ad-
justment. During recording, the input signal FUNCTION will au-
tomatically switch to VIDEO.
(After recording, press the  – 

0 button without stopping will

return to the position where recording was started.)

1. Press 

[FUNCTION]

 button to select VIDEO. (This step is not

necessary if the above test mode has already been set.)

2. Insert a tape into deck B.
3. After press 

[    REC]

 button, press

P button, then recording

start.

4. Mode: Record

5. Mode:  Playback

6. Confirm playback the signal recorded in step 3 become ad-

justable level as follows.
If these levels do not adjustable level, adjustment the RV301
(L-CH) and RV351 (R-CH) on the MAIN board to repeat steps
4 and 5.

Adjustable level:
CN301 PB level:  47.2 to 53.0 mV (–24.3 to –23.3 dB)
Adjustment Location:  MAIN board

[MAIN  BOARD] (Component Side)

[AUDIO  BOARD]  (Component Side)

[LEAF  SW  BOARD]  (Component Side)

r

r

attenuator

set

MD/VIDEO (AUDIO) IN

1) 315 Hz
2) 10 kHz

50 mV (–23.8 dB)







600 

Ω

blank tape
CN-123

AF OSC

+

–

+

+

–

–

+
–

set

recorded
portion

MAIN board
CN301 (Pin 

3

: L-CH)

(Pin 

1

: R-CH)

level meter

set

MD/VIDEO (AUDIO) IN
315 Hz, 50 mV (–23.8 dB)

blank tape
CS-123

600 

Ω

attenuator

AF OSC

+

–

+

+

–

–

+
–

set

recorded
portion

MAIN board
CN301 (Pin 

3

: L-CH)

(Pin 

1

: R-CH)

level meter

REC LEVEL

1

3

RV301

L

RV351

R

CN106

CN301

CN107

















RV401

RV301

RV341

RV311

RV411

IC602

CN601

L

R

R L





 





 

RV441

PB LEVEL

– DECK B –

REC BIAS

L

R





 

PB LEVEL

– DECK A –

TAPE SPEED

RV1002

RV1001

(NORMAL)  (HIGH)

CN1001





















– 16 –

0 dB=1 µV

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 MW
Tuned Level Adjustment.

Band:  MW
Procedure:
1. Set the output of SSG so that the input level of the set be-

comes 55 dB.

2. Tune the set to 1,050 kHz.
3. Adjust RV41 to the point (moment) when the TUNED indica-

tor will change from going off to going on.

Adjustment Location :  TCB board

This adjustment should be performed after the MW Tuned Level
Adjustment due to the same adjustment element.

Band:  FM
Procedure:
1. Supply a 25 dBµ 98 MHz signal from the ANTENNA termi-

nal.

2. Tune the set to 98 MHz.
3. If the TUNED indicator does not light, adjust RV42 to the

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

Adjustment Location:  TCB board

Carrier frequency   : 98 MHz
Modulation              : AUDIO 1 kHz, 75 kHz
                                 deviation (100%)

FM ANTENNA terminal
(TM1) (75 

Ω

 open)

75 

Ω

 coaxial

set

FM RF stereo signal
generator

AM RF  SSG

loop antenna

set

loop antenna

(Supplied accessories)

60 cm

MW ANTENNA

terminal (TM1)

30% amplitude

modulation by

400 Hz signal

Field strength dB (

µ

V/m) =SSG output level dB (

µ

V/m) –26 dB.