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21
HCD-GN880
SECTION 5
MECHANICAL ADJUSTMENTS
SECTION 6
ELECTRICAL ADJUSTMENTS
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
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
3.06 N • m to 6.96 N • m
FWD
CQ-102C
31 to 71 g • cm
(0.43 – 0.98 oz • inch)
FWD
0.19 N • m to 0.58 N • m
back tension
CQ-102C
2 to 6 g • cm
(0.02 – 0.08 oz • inch)
3.06 N • m to 6.96 N • m
REV
CQ-102RC
31 to 71 g • cm
(0.43 – 0.98 oz • inch)
0.19 N • m to 0.58 N • m
REV
CQ-102RC
2 to 6 g • cm
back tension
(0.02 – 0.08 oz • inch)
6.96 N • m to 14.02 N • m
FF/REW
CQ-201B
71 to 143 g • cm
(0.98 – 1.99 oz • inch)
9.80 N • m
FWD tension
CQ-403A
100 g or more
(3.53 oz or more)
9.80 N • m
REV tension
CQ-403R
100 g or more
(3.53 oz or more)
Mode
Torque meter
Meter reading
0 dB=0.775 V
DECK SECTION
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
RECORD/PLAYBACK HEAD AZIMUTH ADJUST-MENT
DECK A DECK B
Note:
Perform this adjustments for both decks
Procedure:
1. Mode: Playback
Tape
Signal
Used for
P-4-A100
10 kHz, –10 dB
Azimuth Adjustment
set
MAIN board
CN510
Pin
1
(L-CH)
Pin
3
(R-CH)
MAIN board
CN510
Pin
2
(GND)
+
–
level meter
test tape
P-4-A100
(10 kHz, –10 dB)