Sony hcd-tb20, Service Manual

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23
HCD-TB20
3.04 – 6.96 mN • m
(31 to 71 g • cm)
(0.43 – 0.98 oz • inch)
0.20 – 0.58 mN • m
(2 to 6 g • cm)
(0.02 – 0.08 oz • inch)
3.04 – 6.96 mN • m
(31 to 71 g • cm)
(0.43 – 0.98 oz • inch)
0.20 – 0.58 mN • m
(2 to 6 g • cm)
(0.02 – 0.08 oz • inch)
6.97 – 14.02 mN • m
(71 to 143 g • cm)
(0.98 – 1.99 oz • inch)
0.98 N • m or more
(100 g or more)
(3.53 oz or more)
0.98 N • m or more
(100 g or more)
(3.53 oz or more)
CQ-102C
CQ-102C
CQ-102RC
CQ-102RC
CQ-201B
CQ-403A
CQ-403R
Precaution
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 demag-
netizer.
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.
Torque Measurement
Record/Playback Head Azimuth Adjustment
Procedure:
1.
Mode : Playback
SECTION 5
MECHANICAL ADJUSTMENTS
Mode
FWD
FWD
back tension
REV
REV
back tension
FF/REW
FWD tension
REV tension
Torque meter Meter reading
SECTION 6
ELECTRICAL ADJUSTMENTS
DECK SECTION 0 dB=0.775V
1. Demagnetize the record/playback head with a head demagnetizer.
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
supply 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.
7. Switches and controls should be set as follows unless otherwise
specified.
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 1 dB of peak.
test tape
P-4-A100
(10kHz, –10dB)
MAIN board
CN322
Pin
5
or TP42 (L-CH)
Pin
9
or TP46 (R-CH)
level meter
set +
–
L-CH
peak
R-CH
peak
screw
position
output
level
within
1 dB
L-CH
peak R-CH
peak
screw
position
within 1dB
Signal Used for Tape
P-4-A100
WS-48B
10 kHz, –10 dB
3 kHz, 0 dB
Azimuth Adjustment
Tape Speed Adjustment