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– 13 –

With the POWER button OFF, short JW801 and JW802 on the
LCD board. (You need a moment for the short.)
The LCD display changes as in the diagram and the unit goes
into test mode.

When you press the 

^ key, the CD rotates and when you press

the 

^ key again, the CD plays (the track servo comes on)(but

no sound is issued).
Pressing the 

^ key starts automatic adjustment and the value

changes, but this value is not a problem.

(Conductor side)

With the unit in test mode, when you press the POWER button
to OFF, test mode ends.

Test mode PLAY status

Connection P oint :  CD/System board (Conductor side)

Check to see that the jitter is less than 9.0 nsec. and RF level is
between 0.55 – 0.85Vp-p.

Í

ALL

SOUND

MEGA BASS

cd

RF level: 
0.55–0.85 Vp-p

VOLT/DIV : 200mV (using 10:1 probe)
TIME/DIV : 500ns

oscilloscope

(AC range)

   TP (RFO)

TP (VC)

CD TEST MODE

SHORT : TEST MODE

OPEN : NORMAL MODE

– 14 –

Connection P oint :  CD/System board (Conductor side)

Press the FF or FR from 3.
Check to see that the traverse signal level is between 200 to
400mVp-p.

After completed with adjustment, press the POWER button to
release the test mode.

Extend the sweep time
for easier view.

200 – 400mVp-p

A

A

B

B

A = B

0V

0V

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

swab :

record/playback/erase head

pinch roller

rubber belts

capstan

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

Meter Reading

Forward

CQ-102C

36 to 61 g • cm

(0.5 to 0.84 oz • inch)

Forward

CQ-102C

2 to 6 g • cm

Back Tension

(0.028 to 0.083 oz • inch)

Reverse

CQ-102RC

36 to 61 g • cm

(0.5 to 0.84 oz • inch)

Reverse

CQ-102RC

2 to 6 g • cm

Back Tension

(0.028 to 0.083 oz • inch)

FF/REW

CQ-201B

61 to 143 g • cm

(0.85 to 1.98 oz • inch)

 Mode

Tension Meter

Meter Reading

FWD

CQ-403A

more than 100g

(more than 3.53 oz)

REV

CQ-403A

more than 100g

(more than 3.53 oz)

0dB = 0.775V

1. The adjustnemts should be performed in the order in the service

manual. (As a general rule playback circuit adjustment should
be completed beforeming recording circuit adjustment.)

2. The adjustments should be performed for bothe L-CH and R-

CH unless otherwise indicated.

Input terminal

LINE IN

source impedance

10k

Ω

input signal level

0.5V (–3.8dB)

Output terminal

LINE OUT

load impedance

47k

Ω

output signal level

0.5V (–3.8dB)

Type

Signal

Used for

P-4-A100

10kHz, –10dB

Azimuth Adjustment

WS-48B

3kHz,

0dB

Tape Speed Adjustment

oscilloscope

(AC range)

   TP (TO)

TP (VC)

– 15 –

Procedure :
1. Mode : FWD playback

2. Turn the adjustment screw for the maximum output levels. If

these levels do not match, turn the adjustment screw until both
of  output levels match together within 1dB.

3. Phase Check

Mode : FWD playback

4. Change the reverse playback mode and repeat the step 1 to 3.
5. After the adjustment, lock the adjustment screw with suitable

locking compound.

Adjustment Location :  – record/playback head –

set

LINE OUT

47k

Ω

level meter

test tape
P-4-A100
(10kHz, –10dB)

L-CH
peak

R-CH
peak

L-CH
peak

R-CH
peak

Screw
position

output
level

within

1 dB

within

1 dB

screw position

V

H

in phase

90

°

45

°

135

°

180

°

good

wrong

set

L-CH

R-CH

screen pattern

test tape
P-4-A100
(10kHz, –10dB)

Osilloscope

LINE OUT

47k

Ω

47k

Ω

– FWD Playback Mode –

1. Set to FWD playback mode.
2. Adjust RV691 so that the frequency counter reading becomes

3,000Hz.

    Standar d v alue :  2,970 to 3,030Hz
3. Set to REV playback mode.

Confirm the frequency should be within the standard value.

4. Confirm the frequency difference between beginning and the

end of tape should be within 1.5% (45Hz).

Adjustment Location :  TC RF board

set

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

frequency counter

LINE OUT

47k

Ω

FWD side REV side

adjustment screw

Mechanism deck

RV691 : 
Tape speed adjustment

TC RF board

– 16 –

RADIO BAND button : AM
Volume : MIN

RADIO BAND button : FM
Volume : MIN

Adjustment Location :  Tuner board (See page 17)

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

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

AM IF ADJUSTMENT

Adjust for a maximum reading on level meter.

CFT1

450kHz

AM  FREQUENCY COVERAGE  ADJUSTMENT

Adjust part

Frequency display

reading on digital

voltmeter.

 L4

  530kHz

 0.8 – 1.2V

Confirmation

1,710kHz

4.4 – 5.4V

AM TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter.

L3

620kHz

CT3

1,400kHz

FM FREQUENCY COVERAGE  ADJUSTMENT

Adjust part

Frequency display

reading on digital

voltmeter

Confirmation

87.5MHz

1.5 – 1.9V

L2

108MHz

3.5 – 4.5V

FM TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter.

L1

87.5MHz

CT1

108MHz

 

(SIDE B)

AM  RF signal
generator

30% amplitude modulation by 400Hz
signal.
Output level : as low as possible

Put the lead-wire
antenna close to 
the set.

FM RF signal
generator

22.5kHz frequency deviation by 
400Hz signal.
Output level : as low as possible

telescopic
antenna
terminal

0.01 

µ

F

set

47k

Ω

+
–

LINE OUT

level meter

+

–

Digital
voltmeter

100k

Ω

TP (VT)

0dB = 1

µ

V