ICF-C620 - Sony Audio Service Manual (repair manual). Page 8

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

swab:

playback head

pinch roller

capstan

rubber belts

idlers

2. Demagnetize the playback head with a head demagnetizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustment apply suitable locking compound to the

parts adjusted.

5. The adjustment should be performed with the rated power supply

voltage unless otherwise noted.

30 – 60 g • cm

Forward

CQ-102C

(0.42 – 0.83 oz • inch)

Fast Forward

55 – 140 g • cm

and Rewind

CQ-201B

(0.76 – 1.94 oz • inch)

Back

1 – 5 g • cm

Tension

CQ-102C

(0.014 – 0.069 oz • inch)

P-4-A063

6.3 kHz, – 10 dB

head azimuth adjustment

WS-48A

3 kHz, 0 dB

tape speed adjustment

Setting :
VOLUME control : mechanical mid

Procedure :
1. Mode : playback

set

test tape
P-4-A063
(6.3 kHz, – 10 dB)

level meter

speaker terminal

2. Turn the adjustment screw to obtain the maximum reading on

level meter.

 Several peaks may appear but take the maximum.

3. After the adjustment, lock the adjustment screw with suitable

locking compound.

± 3 %

VR2

2,910 to 3,090 Hz

Frequency difference between the beginning and the end of the tape
should be within ± 1% (30 Hz).

Adjustment Location : main board

set

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

speed checker
LFM-30
           or
digital frequency
counter

speaker terminal

Setting :
VOLUME control : mechanical mid

Procedure :
1. Mode : playback

adjustment screw

8 

Ω

8 

Ω