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13

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

swab :

record/playback head

pinch roller

erase head

rubber belts

capstan

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

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

3. Do not use a magnetized screwdriver for the adjustments.
4. The adjustments should be performed with the rated power sup-

ply voltage (12V) unless otherwise noted.

Torque

Torque Meter

Meter Reading

1.77 – 5.88 mN•m

Forward

CQ-102C

(18 – 60 g•cm)

(0.25 – 0.83 oz•inch)

Forward

0.1 – 0.49 mN•m

Back Tension

CQ-102C

(1.0 – 5.0 g•cm)

(0.014 – 0.069 oz•inch)

4.42 – 9.31 mN•m

Fast Forward

CQ-201B

(45 – 95 g•cm)

(0.62 – 1.32 oz•inch)

4.42 – 9.31 mN•m

Rewind

CQ-201B

(45 – 95 g•cm)

(0.62 – 1.32 oz•inch)

Torque Meter

Meter Reading

CQ-403A

more than 60g

(more than 2.12 oz)

Output terminal

HP OUT

load impedance

32 

Ω

output signal level

0.25V (–10dB)

Type

Signal

Used for

WS-48A

3kHz, 0dB

Tape Speed Adjustment

Mode : Playback

Adjustment so than the value on the digital frequency counter is
3,000 Hz.

Adjustment Value : 3,000Hz
Standard Value : 2,940 - 3,060Hz

Frequency difference between the beginning and the end of the tape
should be within 1.5% (45Hz).

set

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

32

Ω

digital frequency
counter

J391 ( 

i

 jack)

 0dB = 0.775V

Adjustment Location : Mechanism deck

14

MW IF ADJUSTMENT

Adjust for a maximum reading on level meter.

T1

450 kHz

(     ): AR

MW FREQUENCY COVERAGE CHECK

Frequency Display

531 kHz

1,611 kHz

(530 kHz)

(1,610 kHz)

Reading on Digital voltmeter

0.9 

± 0.4 V

5.2 

± 0.5V

Adjustment Part

<confirmation>

<confirmation>

(     ): AR

MW TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter.

L3

CT3

621kHz (620 kHz)

1,404 kHz (1,400kHz)

LW FREQUENCY COVERAGE CHECK

Frequency Display

153 kHz

279 kHz

Reading on Digital voltmeter

0.6 

± 0.2 V

5.0 

± 0.2V

Adjustment Part

< L 4 >

<confirmation>

LW TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter.

L3

CT5

162 kHz

261 kHz

FM IF ADJUSTMENT

Adjust for a maximum reading on level meter.

T2

10.7 MHz

FM FREQUENCY COVERAGE ADJUSTMENT

Frequency Display

87.5 MHz

108 MHz

Reading on Digital voltmeter

1.3 

± 0.4 V

3.0 

± 0.3 V

Adjustment Part

<confirmation>

L2

FM TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter.

L1

CT1

87.5 MHz

108 MHz

Adjustment Location : Main board (See page 16)

• Repeat the procedures in each adjustment several times, and the

frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.

Function switch : MW/LW
Volume

: MIN

Function switch : FM
Volume

: MIN

µF

 0dB = 1 

µV

J391 ( i jack)

Ω

Ω

15

Focus Bias Check
1. Connect the oscilloscope between TP (RF) and GND on CD

board.

2. Insert the disc (YEDS-18). (Part No. : 3-702-101-01) (CD)
3. Press the u button two times (LPC ON).
4. Confirm that the oscilloscope waveform is as shown in the fig-

ure below. (eye pattern)
A good eye pattern means that the diamond shape (

◊) in the cen-

ter of the waveform can be clearly distinguished.

5. Press the u button.(LPC OFF)
6. Perform confirmation in step 4 again.

•

RF Signal Reference Waveform (eye pattern)

Perform all CD section check and all adjustments in the test mode.
How to put the set into CD test mode
1. Press the POWER button turn the set ON.
2. Press the FUNCTION button to select CD.
3. Set Tset mode by momentarlly shorting both side of TEST A.
4. Press the x button two times. The set is into CD test mode.

(

88 is displayed)

5. Turn the power off to release test mode.

When observing the eye pattern, set the oscilloscope for AC range
and raise certical sensitivity.

CONTROL-1 BOARD

S404

S402

S403

S401

KH402

D401

R401

R402

R403
R404

R407

 

 

 

SOUND

(TEST A)

MODE

GAME/LINE

GAME Xpand

GAME Xpand

TEST mode : momentarily short

(Conductor side)

1-68

Q701

C729

C730

R730

R728

R729

C704

R708

C72

8

R726

R707

C70

FB70

C736

C734

IC701

R709

C705

R704

R702

R711

R710

R703
R705
R701

C703

C731

R706

R727

R712

R7

C708

C751

JC703

C743

C744

C74

C742

JW707

C707

C717

C732

C702

C701

JW708

JW709

JW713

JW714

JW723

JW

JW725

JW726

C750

C

7

C747

JW711

C733

C706

JW712

JW710

oscilloscope

(AC range)

TP (RF)

(GND)

CD BOARD   (Conductor side)

TP (RF)

16

TUNER BOARD   

(Component side)

CT1: FM Tracking Adjustment

L1: FM Tracking Adjustment

L3: MW Tracking Adjustment

CT3: MW Tracking Adjustment

CT5: LW Tracking Adjustment

CNP1

L4: LW Frequency Coverage Adjustment 

T1: MW IF Adjustment 

L3: LW Tracking Adjustment 

T2: FM IF Adjustment 

L2: FM Frequency Coverage Adjustment