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9

A

B

C

1

A

C

A

B

2

A

B

3

5

6

2

2

4

3

1

10

2

1

two precision screws
(P2 

×

 2)

Note: Mount the motor so that the 

angle between      of the 
motor and the hole for the 
screw      becomes 30

°

 as

shown in this figure.

capstan/reel motor
(M901)

30˚

11

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 3,000 Hz.

Specification: Constant speed

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

 2.95 – 6.37 mN•m

Forward

CQ-102C

(30 – 65 g•cm)

(0.42 – 0.90 oz•inch)

Forward

0.05 – 0.44 mN•m

CQ-102C

(0.5 – 4.5g•cm)

Back Tension

(0.01 – 0.06 oz•inch)

2.95 – 6.37 mN•m

Reverse

CQ-102RC

(30 – 65 g•cm)

(0.42 – 0.90 oz•inch)

Reverse

0.05 – 0.44 mN•m

CQ-102RC

(0.5 – 4.5g•cm)

Back Tension

(0.01 – 0.06 oz•inch)

5.89 – 19.61 mN•m

FF, REW

CQ-201B

(60 – 200 g•cm)

(0.83 – 2.78 oz•inch)

Mode

Tension Meter

Meter Reading

Forward

CQ-403A

more than 60 g

(more than 2.12 oz)

Reverse

CQ-403R

more than 60 g

(more than 2.12 oz)

0 dB=0.775 V

Frequency counter

2,955 to 3,075 Hz

Ω

Tuner section adjustments are done automatically in this set.

12

2.6 Vp-p

26.6 

µ

s

2.6 Vp-p

54.2 ns

184 mVp-p

97 ns

5.1 Vp-p

30.6 

µ

s

Note on Schematic Diagram:
• All capacitors are in 

µ

F unless otherwise noted.  pF: 

µµ

F

50 WV or less are not indicated except for electrolytics
and tantalums.

• All resistors are in 

Ω

 and 

1

/

4

 

W or less unless otherwise

specified.

•

C

: panel designation.

•

A

: B+ Line.

• Power voltage is dc 14.4V and fed with regulated dc power

supply from ACC and BATT cords.

• Voltages and waveforms are dc with respect to ground

under no-signal (detuned) conditions.
no mark : FM
(

) : AM

〈〈

 

〉〉

: TAPE PLAYBACK

∗

: Impossible to measure

• Voltages are taken with a VOM (Input impedance 10 M

Ω

).

Voltage variations may be noted due to normal produc-
tion tolerances.

• Waveforms are taken with a oscilloscope.

Voltage variations may be noted due to normal produc-
tion tolerances.

• Circled numbers refer to waveforms.

• Signal path.

F

: FM

f

: AM

E

: TAPE PLAYBACK

L

: BUS AUDIO IN

Note on Printed Wiring Board:
•

X

: parts extracted from the component side.

•

Y

: parts extracted from the conductor side.

•

: Pattern from the side which enables seeing.

Caution:
Pattern face side:

Parts on the pattern face side seen from

(Conductor Side)

the pattern face are indicated.

Parts face side:

Parts on the parts face side seen from

(Component Side) the parts face are indicated.

1

IC1 

1

 (XTOUT)

2

IC501 

qs

 (OSCOUT)

3

IC501 

qh

 (XOUT)

4

IC901 

y;

 (OSC)