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— 9 —

(Perform after removing the front panel.)

1

Turn the cam to the
direction of arrow.

2

Pull-out the disc tray.

5

Remove the disc tray.

4

Two claws

3

Flat type wire (8 core)

Note: When installing the Disc tray, pull around the flat type wire to

pass through the claw 

A

 and claw 

B

, as shown in the figure.

claw 

A

claw 

B

— 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 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 sup-

ply voltage unless otherwise noted.

Torque

Torque meter

FWD

Meter reading

FWD
back tension

FF/REW

FWD tension

CQ-102C

CQ-102C

CQ-201B

CQ-403A

30 to 80g • cm

(0.41 – 1.11 oz • inch)

1.5 to 5.5g • cm

(0.02 – 0.08 oz • inch)

100g or more

(3.53 oz or more)

55 to 130g • cm

(0.76 – 1.80 oz • inch)

1. Demagnetize the record/playback head with a head damagnetizer.

(Do not bring the head demagnetizer close to the erase head.)

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

parts adjusted.

4. The adjustments 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

Note : Perform this adjustments for both decks.

Procedure :
1. Mode : Playback

main board
CN307
Pin 

2

 (GND)

set

test tape
P-4-A100
(10kHz, –10dB)

main board
CN307
Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

level meter

+
–

— 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.

4. After the adjustments, apply suitable locking compound to the

parts adjusted.

Procedure :
Mode : Playback

4 5 ˚

9 0 ˚

135˚

180˚

wrong

good

in phase

L

R

set

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

3. Mode : Playback

test tape
P-4-A100
(10kHz, –10dB)

Pin 

2

 (GND)

main board
CN307
Pin 

1

 (L-CH)

oscilloscope

Pin 

3

 (R-CH)

Waveform of oscilloscope

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

set

frequency counter

main board
CN307 Pin 

1

 (L-CH)

Pin 

3

 (R-CH)

1. Insert the WS-48B into the deck B, and playback.
2. Adjust the RV380 so that the frequency counter reading becomes

3000 ± 10 Hz.

3. Stop the deck B. Insert the WS-48B into the deck A to playback.

Be sure to check that the difference of the frequency compared
with the deck B becomes within +2% and –0.5%.

4. Insert the CS-123 (blank tape) into the deck A and insert the

WS-48B into the deck B, then playback them simultaneously.
Be sure to check that the deck B’s frequency counter reading
becomes 3000  ± 50 Hz.

Adjustment Location : MAIN board

Procedure :
Mode : Playback

level meter

set

Deck A is RV301 (L-CH) and RV401 (R-CH),
Deck B is RV302 (L-CH) and RV402 (R-CH)
so that adjustment within the following adjustment level.

CN307 playback level: 301.5 to 338.3 mV (–8.2 to –7.2 dB)
level difference between the channels: within ±0.5 dB

Adjustment Location : MAIN board

main board
CN307 Pin 

1

 (L-CH)

Pin 

3

 (R-CH)

Adjustment screws
REC/PB head (deck B)
or PB hear (deck A)

output
level

within 1dB

L-CH
peak

R-CH
peak

screw
position

within
1dB

L-CH
peak

screw
position

R-CH
peak

+
–

— 12 —

Procedure :
1. Mode : Record

2. Mode : Playback

2. Mode: Playback

VIDEO IN
1) 315Hz
2) 10kHz

AF OSC

attenuator

blank tape
CS-123

set

600 

Ω

} 51.2 mV (–23.6 dB)

Confirm playback the signal recorded in step 1 become adjustment
level as follows.
If these levels do not adjustment level, adjustment the RV304 (L-
CH) and RV404 (R-CH) on the main board to repeat steps 1 and 2.

Adjustment level : Playback output of 10kHz level diffrence

against 315Hz reference should be ±0.5 dB.

Adjustment Location : MAIN board

Procedure :
1. Mode: Record

main board
CN307 Pin 

1

 (L-CH)

Pin 

3

 (R-CH)

set

recorded
position

level meter

attenuator

600 

Ω

set

AF OSC

blank tape
CS-123

VIDEO IN
315Hz 51.2 mV (–23.6 dB)

level meter

recorded
portion

set

main board
CN307 Pin 

1

 (L-CH)

Pin 

3

 (R-CH)

Confirm playback the signal recorded in step 1 become adjustment
level as follows.
If these levels do not adjustment level, adjustment the RV303 (L-
CH) and RV403 (R-CH) on the main board to repeat steps 1 and 2.

Adjustment level :
CN307 playback level : 47.2 to 53.0 mV (–24.3 to –23.3 dB)

CN307

CN308

RV303

IC303

RV403

RV401

RV304

RV
402

RV301

RV404

RV380

[MAIN BOARD] (Component Side)

RV
302