Mechanical Adjustments; Electrical Adjustments - Sony HCD-HPZ7 Service Manual

SECTION 5

MECHANICAL ADJUSTMENTS

• Precaution
1. Clean the following parts with a denatured-alcohol-moistened
swab :
record/playback head
erase head
capstan
2. Demagnetize the record/playback head with a head
demagnetizer. (Do not bring the head magnetizer close to the
erase head.)
3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustments, appiy 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
FF CQ-201B
REW CQ-201B
• Tape Tension Measurement
Mode Tension Meter
FWD CQ-403A
pinch roller
rubber belts
idlers
Meter reading
2.95 – 6.86 mN • m
(30 to 70 g • cm)
(0.42 – 0.97 oz • inch)
0.15 – 5.39 mN • m
(1.5 to 5.5 g • cm)
(0.021 – 0.076 oz • inch)
more than 5.89 mN • m
(more than 60 g • cm)
(more than 0.83 oz • inch)
more than 5.89 mN • m
(more than 60 g • cm)
(more than 0.83 oz • inch)
Meter Reading
more than 100 g
(more than 3.53 oz)
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.
• Test Tape
Tape Signal
P-4-A063 6.3 kHz, -10 dB
RECORD/PLAYBACK HEAD AZIMUTH ADJUSTMENT
Procedure:
1. Mode: Playback
test tape
P-4-A063
(6.3 kHz, −10 dB)
set
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 1dB of peak.
within
L-CH
1dB
peak
Output
level
R-CH
peak
Screw
position
3. Mode: Playback
test tape
HEADPHONE board
P-4-A063
(6.3 kHz, −10 dB)
PHONES jack
(J321)
set
waveform of oscilloscope
in phase 45°
good
4. After the adjustments, apply suitable locking compound to
the pats adjusted.
HCD-HPZ7/HPZ9
Used for
Azimuth Adjustment
HEADPHONE board
PHONES jack
(J321)
level meter
+
–
within
1dB
Screw
position
L-CH R-CH
peak
peak
oscilloscope
V H
90° 135° 180°
wrong
53