Mechanical Adjustments; Electrical Adjustments - Sony HCD-GR3 Service Manual

SECTION 4

MECHANICAL ADJUSTMENTS

PRECAUTION
1. Clean the following parts with a denatured alcohol-moistened
swab :
record/playback heads
erase head
capstan
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
Torque Torque meter
FWD CQ-102C
FWD
CQ-102C
back tension
FF/REW
CQ-201B
FWD tension
CQ-403A
pinch rollers
rubber belts
idlers
Meter reading
30 to 80g • cm
(0.41 – 1.11 oz • inch)
1.5 to 5.5g • cm
(0.02 – 0.08 oz • inch)
55 to 130g • cm
(0.76 – 1.80 oz • inch)
100g or more
(3.53 oz or more)

ELECTRICAL ADJUSTMENTS

DECK SECTION 0 dB=0.775V
1. Demagnetize the record/playback head with a head damagnetizer.
(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 adjusted.
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 adjustment
should be completed before performing recording circuit adjust-
ment.)
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.
Tape
P-4-A100
WS-48B
P-4-L300
Record/Playback Head Azimuth Adjustment
(Deck A, Deck B)
Note : Perform this adjustments for both decks.
Procedure :
1. Mode : Playback
test tape
P-4-A100
(10kHz, –10dB)
— 10 —
SECTION 5
Signal Used for
10 kHz, –10 dB Azimuth Adjustment
3 kHz, 0 dB Tape Speed Adjustment
315 Hz, 0 dB Level Adjustment
main board
CN307
level meter
Pin 3 (L-CH)
Pin 1 (R-CH)
set
+
–
main board
CN307
Pin 2 (GND)