Mechanical Adjustments; Electrical Adjustments; Deck Section - Sony HCD-RG88 Service Manual

HCD-RG88
SECTION 5

MECHANICAL ADJUSTMENTS

Precaution
1. Clean the following parts with a denatured alcohol-moistened
swab:
record/playback heads
erase head rubber belts
capstan idlers
2. Demagnetize the record/playback head with a head
demagnetizer.
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
Mode Torque meter
FWD
CQ-102C
FWD
CQ-102C
back tension
REV CQ-102RC
REV
CQ-102RC
back tension
FF/REW CQ-201B
FWD tension CQ-403A
REV tension CQ-403R
18
pinch rollers
Meter reading
3.06 N • m to 6.96 N • m
31 to 71 g • cm
(0.43 – 0.98 oz • inch)
0.19 N • m to 0.58 N • m
2 to 6 g • cm
(0.02 – 0.08 oz • inch)
3.06 N • m to 6.96 N • m
31 to 71 g • cm
(0.43 – 0.98 oz • inch)
0.19 N • m to 0.58 N • m
2 to 6 g • cm
(0.02 – 0.08 oz • inch)
6.96 N • m to 14.02 N • m
71 to 143 g • cm
(0.98 – 1.99 oz • inch)
9.80 N • m
100 g or more
(3.53 oz or more)
9.80 N • m
100 g or more
(3.53 oz or more)
SECTION 6

ELECTRICAL ADJUSTMENTS

DECK SECTION

0 dB=0.775 V
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 adjust.
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.
• Test Tape
Tape Signal
P-4-A100 10 kHz, –10 dB
WS-48B 3 kHz, 0 dB
RECORD/PLAYBACK HEAD AZIMUTH ADJUST-
MENT
DECK A DECK B
Note: Perform this adjustments for both decks
Procedure:
1. Mode: Playback
test tape
MAIN board
P-4-A100
CN301
(10 kHz, –10 dB)
Pin 1 (L-CH)
Pin 3 (R-CH)
set
MAIN board
CN301
Pin 2 (GND)
Used for
Azimuth Adjustment
Tape Speed Adjustment
level meter
+
–