Read Sony CMT-LX50WMR / HCD-LX50WMR Service Manual online
HCD-LX50WMR
HCD-LX50WMR
11
11
FM TUNE LEVEL CHECK
signal
generator
set
Procedure:
1. Turn on the set.
2. Input the following signal from signal generator to FM antenna
1. Turn on the set.
2. Input the following signal from signal generator to FM antenna
input directly.
Carrier frequency : A = 87.5 MHz, B = 98 MHz, C = 108 MHz
Deviation
Deviation
: 75 kHz
Modulation
: 1 kHz
ANT input
: 35 dBu (EMF)
Note: Use 75 ohm coaxial cable to connect signal generator and the set.
You cannot use video cable for checking.
Use signal generator whose output impedance is 75 ohm.
3. Set to FM tuner function and tune A, B and C signals.
4. Confi rm “TUNED” is lit on the display for A, B and C signals.
4. Confi rm “TUNED” is lit on the display for A, B and C signals.
When the selected station signal is received in good condition,
“TUNED” is displayed.
“TUNED” is displayed.
CD SECTION
Note:
1. CD Block is basically constructed to operate without adjustment.
2. Use YEDS-18 disc (Part No. 3-702-101-01) unless otherwise indicat-
1. CD Block is basically constructed to operate without adjustment.
2. Use YEDS-18 disc (Part No. 3-702-101-01) unless otherwise indicat-
ed.
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 specifi ed value with the following checks.
5. Check the focus bias check when optical pick-up block is replaced.
FOCUS BIAS CHECK
+
–
–
CD board
TP122 (RFEQO)
TP124 (VC)
oscilloscope
(DC range)
Procedure:
1. Connect oscilloscope to TP122 (RFEQO) and TP124 (VC) on
1. Connect oscilloscope to TP122 (RFEQO) and TP124 (VC) on
the CD board.
2. Press the [
?/1
] button to turn the power on.
3. Press the [FUNCTION +] button to select CD function.
4. Set the disc (YEDS-18) and press the [
4. Set the disc (YEDS-18) and press the [
7
] button to playback.
5. Confi rm that oscilloscope waveform is as shown in the fi gure
below. (eye pattern)
A good eye pattern means that the diamond shape (
◊) in the
center of the waveform can be clearly distinguished.
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
level: 1.2 ± 0.3 Vp-p
Checking Location:
IC101
TP124 (VC)
TP122
(RFEQ)
– CD Board (Conductor Side) –
SECTION 4
ELECTRICAL ADJUSTMENTS
TUNER SECTION 0 dB = 1 μV
[AM]
Setting:
Function: TUNER
Band: AM
Setting:
Function: TUNER
Band: AM
AM RF signal
generator
30% amplitude
modulation by
400 Hz signal
60 cm
set
loop antenna A
loop antenna B
[FM]
Setting:
Function: TUNER
Band: FM
Setting:
Function: TUNER
Band: FM
FM RF signal
generator
1 kHz frequency
deviation by FM 75 kHz
signal
Output level:
as low as possible
+
–
level meter
MAIN board
JW828
(GND)
MAIN board
TP (TUNER OUT L-ch)
set
MAIN board
J802 pin
MAIN board
J802 pin
digital voltmeter
JW821 (VT)
JW828 (GND)
10 k
Ω
MAIN board
• Repeat the procedures in each adjustment several times, and
the tracking adjustments should be fi nally done by the trimmer
capacitors.
capacitors.
• Remove FM antenna in FM adjustment.
( ): Chilean, Peruvian and Mexican models
AM VT VOLTAGE CONFIRMATION
Frequency Display Reading on Digital Voltmeter
531 (530) kHz
1.6 ± 0.3 V
1,602 (1,710) kHz
7 (8) ± 0.5 V
( ): Chilean, Peruvian and Mexican models
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L851
603 (620) kHz
FM VT VOLTAGE ADJUSTMENT
Adjustment Part Frequency Display Reading on Digital Voltmeter
L805
87.5 MHz
1.7 ± 0.1 V
Confi rmation
108 MHz
6.2 ± 0.5 V
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L804
98 MHz
FM DETECTOR ADJUSTMENT
Setting:
Function: TUNER
BAND button: FM
Setting:
Function: TUNER
BAND button: FM
set
MAIN board
TP (TUNER OUT L-ch)
TP (TUNER OUT L-ch)
MAIN board
JW828 (GND)
JW828 (GND)
Carrier frequency : 98 MHz
Modulation
Modulation
: deviation by
FM 75 kHz
Output level
: 60 dB
FM RF Signal
generator
generator
1. Tune the set to 98 MHz.
2. Adjust L806 so that modulation distortion may become the
2. Adjust L806 so that modulation distortion may become the
best in the vicinity of the maximum value where the tuner out
level becomes –15 dBs or more.
level becomes –15 dBs or more.
Adjustment Location:
L851
AM Tracking
Adjustment
JW821
(VT)
JW828
(GND)
TP
(TUNER
OUT L-ch)
J802
1
3
L804
FM Tracking
Adjustment
L805
FM VT Voltage
Adjustment
TP
(TUNER
OUT R-ch)
L806
FM Detector
Adjustment
– MAIN Board
(Component Side) –
(Component Side) –
– MAIN Board
(Conductor Side) –
(Conductor Side) –
Click on the first or last page to see other CMT-LX50WMR / HCD-LX50WMR service manuals if exist.