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– 9 –

A

1

Push an arrow 

A

 part.

2

Removal the cassette holder (x)
to direction of the arrow.

– 10 –

Mode

Tension Meter

Meter Reading

Forward

CQ-403A

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.

Mode

Torque Meter

Meter Reading

Forward

CQ-102C

25 – 55 g•cm

(0.35 – 0.76 oz•inch)

Forward

CQ-102C

1.5 – 4 g•cm

Back Tension

(0.02 – 0.06 oz•inch)

Reverse

CQ-102RC

25 – 55 g•cm

(0.35 – 0.76 oz•inch)

Reverse

CQ-102RC

1.5 – 4 g•cm

Back Tension

(0.02 – 0.06 oz•inch)

FF, REW

CQ-201B

50 – 150 g•cm

(0.69 – 2.08 oz•inch)

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 2 dB.

3. Check the phase in the FWD PB mode.

Type

 Signal

 Used for

P-4-A063

6.3 kHz, –10 dB

head azimuth adjustment

WS-48A

3 kHz, 0 dB

tape speed adjustment

screw
position

L-CH
peak

within
2 dB

output
level

L-CH
peak

R-CH
peak

within
2 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

level 

meter

test tape 
P-4-A063
(6.3 kHz, –10 dB)

set

speaker out terminal

4 

Ω

+
–

– 11 –

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.

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 speed checker or frequency counter becomes in
specification.

Specification: Constant speed

Adjustment Location: See page 12.

See the adjustment location from on page 12 for the
adjustment.

Speed checker

Frequency counter

–2 to +3%

2,940 to 3,090 Hz

A tuner section is no adjustment.

FWD 

REV 











adjustment 
screws

+

–

speed checker

or

frequency counter

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

speaker out terminal

set

4 

Ω

– 12 –

Tape Speed Adjustment

CN901

– SET UPPER VIEW –