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— 9 —

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

swab:

record/playback heads

pinch rollers

erase head

rubber belts

capstan

idlers

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.

1. Demagnetize the record/playback head with a head damagnetizer.
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the

parts adjusted.

4. The adjustments should be performed with the rated power sup-

ply voltage unless otherwise noted.

5. The adjustments should be performed in the order given in this

service manual. (As a general rule, playback circuit adjustment
should be completed before performing recording circuit
adjustment.)

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

CH.

Used for

10 kHz, –10 dB

3 kHz, 0 dB

Azimuth Adjustment

Tape Speed Adjustment

Tape

P-4-A100

WS-48B

Signal

Note: Perform this adjustments for both decks.

Procedure:
1. Mode : Playback

test tape
P-4-A100
(10kHz, –10dB)

set

SPEAKER
terminal (JK302)

level meter

+

–

FWD

FWD
back tension

1 to 5 g • cm

(0.01 - 0.07 oz • inch)

FF/REW

40 to 70 g • cm

(0.56 - 0.97 oz • inch)

Torque

Torque meter

Meter reading

CQ-102C

CQ-102C

CQ-201B

55 to 140 g • cm

(0.76 - 1.94 oz • inch)

— 10 —

2. Turn the adjustment screw and check output peaks. If the peaks

do not match for L-CH and R-CH, turn the adjustment screw so
that outputs match within 2 dB of peak.

3. Mode: Playback

good

R

L-CH
peak

R-CH
peak

output
level

screw
position

within 2dB

L-CH
peak

R-CH
peak

screw
position

test tape
P-4-A100
(10kHz, –10dB)

SPEKER
terminal (JK302)
(L-CH)

set

L

oscilloscope

SPEKER
terminal (JK302)
(R-CH)

Waveform of oscilloscope

wrong

in phase

4 5 ˚

9 0 ˚

135˚

180˚

within
2dB

4. After the adjustments, apply suitable locking compound to the

parts adjusted.

Adjustment screws
REC/PB head (deck A)
or PB head (deck B)

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

set

SPEAKER
terminal (JK302)

frequency counter

+

Procedure:
1. Mode: Playback

–

2. Adjust the SFR201 so that the frequency counter reads 3,000 Hz

± 90Hz.

Adjustment Location: MAIN board

W. RMS (JIS) within 0.3%
(test tape: WS-48B)

SFR201

Tape Speed

CN204

— 11 —

0 dB=1µV

Procedure:
1. Set the reception frequency of the unit to 530 kHz.
2. Adjust L105 for 1.2 ± 0.05 V reading on the DC voltmeter.
3. Set the reception frequency of the unit to 1,710 kHz.
4. Confirm that the voltage reading on the DC voltmeter is within

8.0 ± 0.5 V.

Adjustment Location:  MAIN board

Procedure:
1. Tune the set to 600 kHz.
2. Set the output of AM RF SSG so that the input level of the set

will become 60 dB (µV/m).

3. Adjust L104 so that when the waveform on the oscilloscope is

maximum, no noise appears.

4. Tune the set to 1,400 kHz.

5. Adjust TC102 so that when the waveform on the oscilloscope is

maximum, no noise appears.

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

tracking adjustment should be finally done by the trimmer
capacitors.

Adjustment Location: MAIN board

DC voltmeter

+

–

Procedure :
1. Set the reception frequency of the unit to 87.5 MHz.
2. Adjust L103 for 1.2 ± 0.05V reading on the DC voltmeter.
3. Set the reception frequency of the unit to 108 MHz.
4. Confirm that the voltage reading on the DC voltmeter is within

7.8 ± 0.5V.

Adjustment Location: MAIN board

+

–

DC voltmeter

TP1

Main board

IF
G
VT

set

loop antenna

AM RF SSG

60cm

Field strength dB (µV/m) = SSG output level dB (µV/m) –26dB.

30% amplitude
modulation by
400Hz signal

Center of
Bar antenna (L104)

TP1

Main board

IF
G
VT

— 12 —

Carrier frequency : 98 MHz
Modulation

: AUDIO 1 kHz, 75 kHz

deviation (100%)

Output level

: 28 dB  (at 75 

Ω

 open)

FM RF SSG

set

75 

Ω

 coaxial

FM ANTENNA terminal
(JK101)

Procedure:
1. Supply a 28 dB 98 MHz signal from the ANTENNA terminal.
2. Tune the set to 98 MHz.
3. Adjust SFR101 to the point (moment) when the TUNED indica-

tor will change from going off to going on.

Adjustment Location: MAIN board

FM RF SSG

oscilloscope

FM ANTENNA terminal (JK101)

SPEAKER terminal (JK302)

set

Carrier frequency : 90 MHz, 106 MHz
Modulation

: AUDIO 1kHz, 75kHz deviation (100%)

Output level

: 20 dB (at 75 

Ω

 open)

+

–

1. Tune the set to 90 MHz.
2. Adjust L102 so that when the waveform on the oscilloscope is

maximum, no noise appears.

3. Tune the set to 106 MHz.
4. Adjust TC101 so that when the waveform on the oscilloscope is

maximum, no noise appears.

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

tracking adjustment should be finally done by the trimmer
capacitors.

Adjustment Location: MAIN board

FM Tuning Voltage

JK101

FM Tracking

AM Tuning Voltage

SFR101

FM Tuned Level

AM Tracking

TC101

TC102

L105

L104

L103

L102

IC103

JK302

IC102

TP1

IF

GND

VT