Sony HCD-DR8AV, Service Manual, Page: 15 / 92

— 15 —
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
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)
MD OUT
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
Mode
FWD
FWD
back tension
REV
REV
back tension
FF/REW
FWD tension
REV tension
Torque meter
CQ-102C
CQ-102C
CQ-102RC
CQ-102RC
CQ-201B
CQ-403A
CQ-403R
Meter reading
31 to 71 g • cm
(0.43 – 0.98 oz • inch)
2 to 6 g • cm
(0.02 – 0.08 oz • inch)
31 to 71 g • cm
(0.43 – 0.98 oz • inch)
2 to 6 g • cm
(0.02 – 0.08 oz • inch)
71 to 143 g • cm
(0.98 – 1.99 oz • inch)
100 g or more
(3.53 oz or more)
100 g or more
(3.53 oz or more)
SECTION 6
ELECTRICAL ADJUSTMENTS
SECTION 5
MECHANICAL 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.
Record/Playback Head Azimuth Adjustment
(Deck A, Deck B)
Note: Perform this adjustments for both decks.
Procedure:
1.
Mode : Playback
Tape Signal Used for
P-4-A100
WS-48B
P-4-L300
10 kHz, –10 dB
3 kHz, 0 dB
315 Hz, 0 dB
Azimuth Adjustment
Tape Speed Adjustment
Level Adjustment