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— 9 —

A

A

5

Disc table

4

Step screw

1

 Screw (BVTP 3x8)

2

Screw (BVTP 3x8)

3

Bracket (BU)

When the Disc table is installed, adjust the positions
of Roller cam and mark 

( as shown in the figure,

then set to the groove of disc table.

— 10 —

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.

Torque

FWD

FWD
back tension

REV

REV
back tension

FWD tension

REV tension

FF/REW

Torque meter

CQ-102C

CQ-102C

CQ-102RC

CQ-102RC

CQ-201B

CQ-403A

CQ-403R

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 adjust-
ment.)

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.

Tape

P-4-A100

WS-48B

P-4-L300

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)

level meter

main board
CN403
Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

test tape
P-4-A100
(10kHz, –10dB)

set

main board
CN403
Pin 

2

— 11 —

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

Pin 

2

L

R

Pin 

1

oscilloscope

Waveform of oscilloscope

good

wrong

in phase

45°

90°

135°

180°

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)

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 ad-
justment 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

L-CH
peak

screw
position

R-CH
peak

within
1dB

output
level

R-CH
peak

L-CH
peak

within 1dB

screw
position

set

FWD side

REV side

Adjustment screw

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)

Note : 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)

1. Insert the 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

Procedure :
Mode : Playback (FWD)

main board
CN403 (Pin 

3

 : L-CH)

(Pin 

1

 : R-CH)

set

— 12 —

LD/VIDEO IN
1) 315Hz
2) 10kHz

50mV (–23.8dB)

blank tape
CS-123

AF OSC

attenuator

600

set

Procedure :
1. Mode : record

2. Mode : Playback

recorded
position

set

level meter

CN 403 (Pin 

3

 : L-CH)

(Pin 

1

 : R-CH)

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

LD/VIDEO IN
315Hz, 50mV (–23.8dB)

AF OSC

attenuator

600

blank tape
CS-123

set

2. Mode : Playback

recorded
position

set

level meter

main board
CN403 (Pin 

3

 : L-CH)

(Pin 

1

 : R-CH)

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)

RV351 REC LEVEL (R-CH)

RV301 REC LEVEL
(L-CH)

1

3

CN403

– DECK B –

RECORD

BIAS

L

RV441 RV341

(NORMAL)

RV651

¬

R

TAPE SPEED

PB

LEVEL

L 

¬

R 

¬

– DECK A –

PB LEVEL

RV301

¬

L

RV401

¬

R

[MD BOARD] (Conductor Side)

(HIGH)

RV652

¬