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13

Mode

Tension Meter

Meter Reading

Forward

CQ-403A

more than 5.89 mN•m

(more than 60 g)

Reverse

CQ-403R

(more than 2.12 oz)

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

swab:

playback head

pinch roller

rubber belt

capstan

idler

2. Demagnetize the playback head with a head demagnetizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. The adjustments should be performed with the power supply

voltage (14.4 V) unless otherwise noted.

With this set, it is not necessary to apply suitable locking
compound to the parts after the azimuth adjustment.

Mode

Torque Meter

Meter Reading

2.46 – 5.39 mN•m

Forward

CQ-102C

(25 – 55 g•cm)

(0.35 – 0.76 oz•inch)

Forward

0.15 – 0.39 mN•m

CQ-102C

(1.5 – 4 g•cm)

Back Tension

(0.02 – 0.06 oz•inch)

2.46 – 5.39 mN•m

Reverse

CQ-102RC

(25 – 55 g•cm)

(0.35 – 0.76 oz•inch)

Reverse

0.15– 0.39 mN•m

CQ-102RC

(1.5 –

4 g•cm)

Back Tension

(0.02 – 0.06 oz•inch)

4.91 – 14.70 mN•m

FF, REW

CQ-201B

(50 – 150 g•cm)

(0.69 – 2.08 oz•inch)

This set have the test mode function. In the test mode, FM RDS S-
Meter, FM Auto Seek/Stop Level and MW Auto Seek/Stop Level
adjustments can be performed easier than it in ordinary proce-
dure.

<Set the Test Mode>
1. Turn ON the regulated power supply. (All LEDs on the set

lights up, and the clock is displayed.)

 Press the 

[OFF]

 button, if the clock is not displayed.

2. Push the 

[4]

 button.

3. Push the 

[5]

 button.

4. Press the 

[1]

 button for more than two seconds.

5. Then the display indicates all lights, the test mode is set.

<Release the Test mode>
1. Push the 

[OFF]

 button.

14

0 dB= 0.775 V

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

this service manual.

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

R-CH.

Procedure:
1. Put the set into the FWD PB mode.

2. Turn the screw and check the output peak value.  Adjust the

screw so that the peak value in channels L and R coincides
within 3 dB.

3. Check the phase in the FWD PB mode.

4. Repeat the above adjustment for the REV PB mode.
5. Check that output level difference between FWD PB mode

and REV PB mode is within 4 dB.

Type

 Signal

 Used for

P-4-A063

6.3 kHz, –10 dB

head azimuth adjustment

WS-48A

3 kHz, 0 dB

tape speed adjustment

Adjustment Location: PB head

Procedure:
1. Put the set into the FWD PB mode.
2. Adjust adjustment resistor for inside capstan motor so that the

reading on the frequency counter becomes in 3,015 Hz.

Specified Value: 2,940 to 3,090 Hz

Adjustment Location: See page 17.

level 

meter

test tape 
P-4-A063
(6.3 kHz, –10 dB)

set

speaker out terminal

4 

Ω

+
–

screw
position

L-CH
peak

within
3 dB

output
level

L-CH
peak

R-CH
peak

within
3 dB

angle

R-CH
peak

test tape 
P-4-A063
(6.3 kHz, –10 dB)

L-CH

R-CH

speaker out terminal

oscilloscope

V

H

+ +

–

–

Screen pattern

in phase

good

wrong

45 

°

90 

°

135 

°

180 

°

4 

Ω

4 

Ω

set

frequency counter

test tape 
WS-48A
(3 kHz, 0 dB)

set

speaker out terminal

–

+

4 

Ω

FWD 

REV 











adjustment 
screws

15

0 dB=1 

µ

V

When the tuner unit is defective, replace it by a new one be-
cause its internal block is difficult to repair.

Adjust the tuner section in the sequence shown below.

1. FM RDS S-Meter Adjustment
2. FM Auto Seek/Stop Level Adjustment
3. FM Stereo Separation Adjustment
4. MW Auto Seek/Stop Level Adjustment

[TUNER]

 button: FM

Procedure:
1. Set to the test mode. (see page 13)
2. Push the 

[TUNER]

 button and set to FM.

Display

3. Push the 

[6]

 button.

4. Adjust RV100 on MAIN board so that the display indication

is “8.4”.

Display

Specified Value: Display indication: 8.2 to 8.6

Adjustment Location: See page 17.

[TUNER]

 button: FM

Procedure:
1. Set to the test mode. (see page 13)
2. Push the 

[TUNER]

 button and set to FM.

Display

3. Adjust with the volume RV3 on TU100 so that the “FM” indi-

cation turns to “FM0” indication on the display window.
But, in case of already indicated “FM0”, turn the RV3 so that
put  out light “0” indication and adjustment.

Display

Adjustment Location: See page 17.

FM RF signal 

generator

dummy

antenna

Carrier frequency : 98.00 MHz
Output level

: 22 dB (12.6 

µ

V)

Mode

: mono

Modulation

: 1 kHz, 22.5 kHz deviation (30%)

antenna
jack (ANT100)

set

50 

Ω

50 

Ω

0.1

µ

F

FM RF signal

generator

Carrier frequency : 98.00 MHz
Output level

: 35 dB (56.2 

µ

V)

Mode

: mono

Modulation

: no modulation

0.01 

µ

F

set

antenna jack (ANT100)

SHUF

REG

SHUF

REG

SHUF

REG

SHUF

REG

16

[TUNER]

 button: FM

L-CH Stereo separation: A-B
R-CH Stereo separation: C-D
The separations of both channels should be equal.

Specified Value: Separation more than 30 dB

Adjustment Location: See page 17.

FM Stereo

Level meter

Level meter

signal generator

connection

reading (dB)

output channel

L-CH

L-CH

A

B

R-CH

L-CH

Adjust RV2 on TU100

for minimum reading.

R-CH

R-CH

C

D

L-CH

R-CH

Adjust RV2 on TU100

for minimum reading.

FM RF signal

generator

Carrier frequency : 98.00 MHz
Output level

: 70 dB (3.2 mV)

Mode

: stereo

Modulation

: main: 1 kHz, 20 kHz deviation (26.7%)
  sub: 1 kHz, 20 kHz deviation (26.7%)

:

 19 kHz pilot: 7.5 kHz deviation (10%)

0.01 

µ

F

set

antenna jack (ANT100)

+
–

speaker out terminal

level meter

10 k

Ω

Make this adjustment after “FM Auto Seek/Stop Level Adjust-
ment”.
Setting:

[TUNER]

 button: MW

Procedure:
1. Set to the test mode. (see page 13)
2. Push the 

[TUNER]

 button and set to FM.

3. Push the 

[MODE]

 button and set to MW.

Display

4. Adjust with the volume RV1 on TU100 so that the “MW” in-

dication turns to “MW0” indication on the display window.
But, in case of already indicated “MW0”, turn the RV1 so that
put out light “

0

” indication and adjustment.

Display

Adjustment Location: See page 17.

SHUF

TP

AM RF signal

generator

Carrier frequency : 999 kHz
30% amplitude
modulation by
1 kHz signal
Output level

: 33 dB (44.7 

µ

V)

(50 

Ω

)

set

AM dummy antenna

30 

Ω

15 pF

65 pF

antenna jack (ANT100)

SHUF

TP