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– 9 –

Tension Meter

Meter Reading

CQ-403A

more than 100 g (3.53 oz)

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 demagne-

tizer. (Do not bring  the head demagnetizer close to the erase
head.)

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

supply voltage unless otherwise noted.

6. Power supply voltage: 12V dc.

Mode

Torque Meter

Meter Reading

Playback

CQ-102C

30 – 75 g•cm

(0.42 – 0.98 oz•inch)

Back tension

CQ-102C

1.5 – 6 g•cm

(0.021 – 0.084 oz•inch)

Rewind

CQ-201B

50 – 130 g•cm

Fast foward

(0.834 – 1.874 oz•inch)

0 dB=0.775 V

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

service manual. (As a general rule. Playback circuit adjust-
ment should be completed before performing recording cir-
cuit adjustment.)

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

unless otherwise indicated.

•

Switch and control position
FUNCTION switch ........................................................ TAPE
MEGA BASS control .............................................. minimum
VOLUME control ................................................... maximum
BALANCE control .................................... mechanical center
KARAOKE MODE switch .............................................. OFF

Procedure:
1. Mode: FWD/REV playback (DECK A)

FWD playback (DECK B)

2. Turn the adjustment screw for the maximum output levels. If

these levels do not match, turn the adjustment screw until both
of output levels match together within 1 dB.

SP OUT

PHONES

Load impedance

3.2 

Ω

32 

Ω

Output  level

0.775 V (0 dB)

0.25 V (–10 dB)

Type

Signal

Used for

WS-48B

3 kHz, 0 dB

Tape speed adjustment

P-4-A063

6.3 kHz, –10 dB

Head azimuth adjustment

+
–

test tape
P-4-A063
(6.3 kHz, –10 dB)

set

32 

Ω

PHONES jack (J301)

level meter

L-CH
peak

L-CH
peak

R-CH
peak

R-CH
peak

Screw
position

output
level

within
1 dB

within
1 dB

Screw
angle

– 10 –

3. Phase Check

Mode: FWD/REV playback (DECK A)

FWD playback (DECK B)

4. Set in the REV mode and repeat the step 1 to 3.
5. After the adjustment, lock the screws with locking compound.

Procedure:
Mode: FWD/REV playback (DECK A)

FWD playback (DECK B)

1. Make sure that the value indicated on the frequency counter

falls into the specification.

2. If out of specification, adjust RV302 so that the value on the

frequency counter becomes 3 kHz.

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

 (High speed: non Adjustment)

Adjustment Location: MAIN board (See page 12.)

Frequency counter

2,910 to 3,090 Hz

+
–

V

H

+

–

Screen pattern

Good

Wrong

in phase 45

°

90

°

135

°

180

°

L-CH

R-CH

set

32 

Ω

32 

Ω

oscilloscope

PHONES jack (J301)

test tape
P-4-A063
(6.3 kHz, –10 dB)

+

–

set

32 

Ω

frequency 
counter

PHONES jack (J301)

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

FWD

REV

DECK A

DECK B

screw driver