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17

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

swab :

record/playback head

pinch roller

erase head

rubber belts

capstan

idlers

2. Demagnetize the record/playback head with a head

demagnetizer. (Do not bring the head magnetizer 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

supply voltage (9V) unless otherwise noted.

2.95 – 6.86 mN • m

FWD

CQ-102C

(30 – 70 g • cm)

(0.42 – 0.97 oz • inch)

FWD

0.15 – 0.53 mN • m

Back Tension

CQ-102C

(1.5 – 5.5 g • cm)

(0.021 – 0.076 oz • inch)

more than 5.88 mN • m

FF

CQ-201B

(more than 60 g • cm)

(more than 0.83 oz • inch)

more than 5.88 mN • m

REW

CQ-201B

(more than 60 g • cm)

(more than 0.83 oz • inch)

FWD

CQ-403A

more than 100 g

(more than 3.53 oz)

i 

jack (J391)

set

32 

Ω

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

digital frequency
counter

TAPE SECTION       0 dB = 0.775 V

load impedance

32 

Ω

output signal level

0.25 V (–10 dB)

WS-48A

3 kHz, 0 dB

tape speed adjustment

Procedure:
Mode: playback
Adjust so that the value on the digital frequency counter is
3,000 Hz.

2,940 to 3,060 Hz

Adjust so that the frequency at the beginning and that at the end of
tape winding are between 2,970 to 3,030 Hz.

Tape speed adjustment
control inside motor
(M971)

18

digital
voltmeter

100 k

Ω

TP (VT)

i

 jack (J391)

set

32 

Ω

level meter
(range: 0.5–5 V ac)

Put the lead-wire
antenna close to
the set.

AM RF signal
generator

30% amplitude
modulation by
400 Hz signal

TP (FM IN)

FM RF signal
generator

0.01 

µ

F

set

75 kHz frequency
deviation by 1 kHz signal
output level : as low as possible

TUNER SECTION       0 dB = 1 

µ

V

Setting:
RADIO BAND•AUTO PRESET button: AM

•

Repeat the procedures in each adjustment several times, and
the frequency coverage and tracking adjustments should be
finally done by the trimmer capacitors.

Adjust for a maximum reading on level meter.

T1

450 kHz

Frequency Display

530 kHz

1,710 kHz

Reading on Digital voltmeter

1.0 

±

 0.05 V

5.3 

±

 0.7 V

Adjustment Part

L4

<confirmation>

Adjust for a maximum reading on level meter.

L3

CT3

620 kHz

1,400 kHz

Adjust for a maximum reading on level meter.

T2

10.7 MHz

Frequency Display

87.5 MHz

108 MHz

Reading on Digital voltmeter

1.3 

±

 0.3 V

3.0 

±

 0.2 V

Adjustment Part

<confirmation>

L2

Adjust for a maximum reading on level meter.

L1

CT1

87.5 MHz

108 MHz

Adjustment Location: See page 19.

Setting:
RADIO BAND•AUTO PRESET button: FM

19

– CD board (conductor side) –

TP

(RF)

TP

(VREF)

CD section adjustments are done automatically in this set.
In case of operation check, confirm that focus bias.

1. Connect the oscilloscope between IC701 pin 4 and pin qa

(or TP (RF) and TP (VREF)).

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

figure below. (eye pattern)
A good eye pattern means that the diamond shape (     ) in the
center of the waveform can be clearly distinguished.

•

RF signal reference waveform (eye pattern)

RF level :
0.85 

±

 0.2 Vp-p

VOLT/DIV : 50 mV (10 : 1 probe in use)
TIME/DIV : 500 nS

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

L4

TP (FM IN)

(CONDUCTOR SIDE)

CT1

IC1

IC2

CT3

L1

L2

T2

T1

L3

– TUNER board (component side) –

L4

AM

FREQUENCY

COVERAGE

ADJUSTMENT

L2

FM

FREQUENCY

COVERAGE

ADJUSTMENT

CT3, L3

AM

TRACKING

ADJUSTMENT

CT1, L1

FM

TRACKING

ADJUSTMENT

T1

AM

IF

ADJUSTMENT

T2

FM

IF

ADJUSTMENT

TP (VT)

(CONDUCTOR SIDE)

20

For Schematic Diagrams.
Note:
• All capacitors are in 

µ

F unless otherwise noted.  (p: pF)

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.

•         

f

: internal component.

•

C

: panel designation.

•

A

: B+ Line.

•

H

: adjustment for repair.

• Total current is measured with no cassette installed.

• Power voltage is dc 12 V and fed with regulated dc power

supply from battery terminal.

• Voltages and waveforms are dc with respect to ground un-

der no-signal (detuned) conditions.

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

Ω

).

Voltage variations may be noted due to normal production
tolerances.

• Waveforms are taken with a oscilloscope.

Voltage variations may be noted due to normal production
tolerances.

• Circled numbers refer to waveforms.

• Signal path.

F

: FM

f

: AM

E

: PB

a

: REC

J

: CD

d

: LINE IN

For Printed Wiring Boards.
Note:
•

X

: parts extracted from the component side.

•        

f

: internal component.

•

: Pattern from the side which enables seeing.

(The other layers' patterns are not indicated.)

• Indication of transistor.

Note: The components identified by mark 

0

 or dotted

line with mark 

0

 are critical for safety.

Replace only with part number specified.

Caution:
Pattern face side:

Parts on the pattern face side seen from

(Side B)

the pattern face are indicated.

Parts face side:

Parts on the parts face side seen from

(Side A)

the parts face are indicated.

C

B

These are omitted.

E

Q

B

These are omitted.

C

E

Q