Sony CMT-NEZ30 / HCD-NEZ30 Service Manual ▷ View online
13
HCD-NEZ30
CD POWER MANEGE
This mode is for switch the CD power supply on/off. Even if this
state pulls out AC plug, it is held.
Procedure:
state pulls out AC plug, it is held.
Procedure:
1. Press the
I/
1
button to turn the power on.
2. Set the FUNCTION to CD.
3. Press the
3. Press the
I/
1
button again to turn the power off (standby).
4. While pressing the
CD
u
button, press the
I/
1
button.
5. If turns power on and display “CD POWER”, then display
“ON” or “OFF”.
•
Precaution
1. Clean the following parts with a denatured-alcohol-moistened
swab :
record/playback head
pinch roller
erase head
rubber belts
capstan
idlers
2. Demagnetize the record/playback head with a head
demagnetizer. (Do not bring the head magnetizer close to the
erase head.)
erase head.)
3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustments, appiy suitable locking compound to
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
Meter Reading
2.95 – 6.86 mN
⋅
m
FWD
CQ-102C
(30 – 70 g
⋅
cm)
(0.42 – 0.97 oz
⋅
inch)
FWD
0.15 – 5.39 mN
⋅
m
Back Tension
CQ-102C
(1.5 – 5.5 g
⋅
cm)
(0.021 – 0.076 oz
⋅
inch)
more than 5.89 mN
⋅
m
FF
CQ-201B
(more than 60 g
⋅
cm)
(more than 0.83 oz
⋅
inch)
more than 5.89 mN
⋅
m
REW
CQ-201B
(more than 60 g
⋅
cm)
(more than 0.83 oz
⋅
inch)
•
Tape Tension Measurement
Mode
Tension Meter
Meter Reading
FWD
CQ-403A
more than 100 g
(more than 3.53 oz)
SECTION 5
MECHANICAL ADJUSTMENTS
14
HCD-NEZ30
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.
so that outputs match within 1dB of peak.
3. Mode: Playback
4. After the adjustments, apply suitable locking compound to
the pats adjusted.
Adjustment Location: Record/Playback/Erase Head
1. Demagnetize the record/playback head with a head
demagnetizer.
2. Do not use a magnetized screwdriver for the adjustments.
•
Test Tape
Tape
Signal
Used for
P-4-A063
6.3 kHz, -10 dB
Azimuth Adjustment
RECORD/PLAYBACK HEAD AZIMUTH ADJUSTMENT
Note:
Remove the cassette lid assy before this adjustment.
Procedure:
1. Mode: Playback
0 dB=0.775 V
DECK SECTION
set
HEAD PHONE board
PHONES jack
(J500)
PHONES jack
(J500)
+
–
–
level meter
test tape
P-4-A063
(6.3 kHz, –10 dB)
P-4-A063
(6.3 kHz, –10 dB)
set
test tape
P-4-A063
(6.3 kHz, –10 dB)
P-4-A063
(6.3 kHz, –10 dB)
oscilloscope
V
H
waveform of oscilloscope
in phase 45
°
90
°
135
°
180
°
good
wrong
HEAD PHONE board
PHONES jack
(J500)
PHONES jack
(J500)
Screw
position
position
L-CH
peak
peak
within
1dB
1dB
Output
level
level
L-CH
peak
peak
R-CH
peak
peak
within
1dB
1dB
Screw
position
position
R-CH
peak
peak
SECTION 6
ELECTRICAL ADJUSTMENTS
15
HCD-NEZ30
CD SECTION
Note:
1.
CD Block is basically constructed to operate without adjustment.
2.
Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3.
Use an oscilloscope with more than 10 M
Ω
impedance.
4.
Clean the object lens by an applicator with neutral detergent when the
signal level is low than specified value with the following checks.
5.
Check the focus bias check when optical pick-up block is replaced.
FOCUS BIAS CHECK
Procedure :
1. Connect oscilloscope to TP (RFACI) and TP (VC) on the CD
board.
2. Press the
I/
1 button to turn the power ON.
3. Set disc (YEDS-18) on the tray and press the
CD
u button
to playback.
4. Confirm that oscilloscope waveform is as shown in the figure
below. (eye pattern)
A good eye pattern means that the diamond shape (
◊
) in the
center of the waveform can be clearly distinguished.
Checking Location:
+
–
–
CD board
TP (RFACI)
TP (VC)
TP (VC)
oscilloscope
(DC range)
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
TIME/DIV: 500 ns
level:
0.9
0.9
±
0.4 Vp-p
TP
(VC)
TP
(RFACI)
IC201
– CD Board (Conductor Side) –
16
HCD-NEZ30
MEMO
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