Sony HCD-V4800, Руководство по обслуживанию

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1. Demagnetize the record/playback head with a head demagne-
tizer. (Do not bring the head demagnetizer close to the erase
head.)
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the
parts adjust.
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 adjust-
ment 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.
8. Set to test mode. (Press key switch same time
GROOVE ENTER/NEXT and DISC 4 buttons.)
To exit from the test mode, press the POWER button.
SECTION 4
MECHANICAL ADJUSTMENTS
SECTION 5
ELECTRICAL ADJUSTMENTS
PRECAUTION
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.
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.
• Torque Measurement
Mode Torque Meter Meter Reading
Forward CQ-102C
36 to 61g•cm
(0.50 – 0.84 oz•inch)
Forward
CQ-102C
2 to 6g•cm
Back Tension (0.026 – 0.082 oz•inch)
Reverse CQ-102RC
36 to 61g•cm
(0.50 – 0.84 oz•inch)
Reverse
CQ-102RC
2 to 6g•cm
Back Tension (0.026 – 0.082 oz•inch)
FF, REW CQ-201B
61 to 143g•cm
(0.85 – 1.98 oz•inch)
Mode Tension Meter Meter Reading
Forward CQ-403A more than 100 g (3.53 oz)
Reverse CQ-403R more than 100 g (3.53 oz)
DECK SECTION 0 dB=0.775 V
Tape Signal Used for
P-4-A100 10 kHz, –10 dB Azimuth Adjustment
WS-48B 3 kHz, 0 dB Tape Speed Adjustment
P-4-L300 315 Hz, 0 dB Level Adjustment
Record/Playback Head Azimuth Adjustment
set
MAIN board
CN207
pin
3
(L-CH)
pin
1
(R-CH)
MAIN board
CN207
pin
2
(GND)
+
–
level meter
test tape
P-4-A100
(10 kHz, –10 dB)
• Tape Tension Measurement
• Test Tape
DECK A DECK B
Note: Perform this adjustments for both decks.
Procedure:
1. Mode: Playback (FWD)
Screw
position
L-CH
peak
within
1 dB
output
level
L-CH
peak R-CH
peak
within
1 dB
Screw
position
R-CH
peak
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.