Electrical Adjustments - Sony HCD-EC69i Service Manual

ELECTRICAL ADJUSTMENTS

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-
ed.
3. Use an oscilloscope with more than 10 MΩ 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
oscilloscope
(DC range)
CD board
TP121 (RFI)
+
TP124 (VC)
–
Procedure:
1. Connect the oscilloscope to TP121 (RFI) and TP124 (VC) on
the CD board.
2. Press the [ ] button to turn the power on, and press the
?/1
[FUNCTION] button to select CD function.
3. Set disc (YEDS-18) and press the [u] button to playback.
4. 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.
level:
1.2 ± 0.3 Vp-p
Checking Location:
– CD Board (Conductor Side) –
TP124
(VC)
TP121
(RFI)
IC101
HCD-EC69i/EC79i/EC99i
All manuals and user guides at all-guides.com
SECTION 5
0 dB = 1 μV
TUNER SECTION
[AM]
Setting:
FUNCTION: AM
60 cm
loop antenna A loop antenna B
AM RF signal
generator
30% amplitude
modulation by
400 Hz signal
MAIN board
Output level: 54 dBuV CN801 pin
[FM]
Setting:
FUNCTION: FM
FM RF signal
generator
MAIN board
CN801 pin
0.01 F
75 kHz frequency
MAIN board
deviation by 1 kHz
CN801 pin
signal
VOLT/DIV: 200 mV
Output level: as low as possible
TIME/DIV: 500 ns
(8 dBuV)
MAIN board
100 kΩ
IC801 pin (TUNER VT)
•
Repeat the procedures in each adjustment several times.
AM FREQUENCY COVERAGE CONFIRMATION
(US, Canadian and Australian models)
Frequency Display
530 kHz
1,710 kHz
AM FREQUENCY COVERAGE CONFIRMATION
(UK model)
Frequency Display
531 kHz
1,602 kHz
AM TRACKING ADJUSTMENT
(US, Canadian and Australian models)
Adjust for a maximum reading on level meter
L805
AM TRACKING ADJUSTMENT (UK model)
Adjust for a maximum reading on level meter
L805
FM FREQUENCY COVERAGE ADJUSTMENT
Adjustment Part
L803
Confi rmation
level meter
32 Ω
+
set
–
FM DETECTOR ADJUSTMENT
Setting:
JACK board
PHONES jack (J492) FUNCTION: FM
FM RF signal
generator
level meter
Carrier frequency: 98 MHz
32 Ω
Modulation:
deviation by FM 75 kHz
+
set Output level: 60 dBuV
–
JACK board
1. Turn the set to 98 MHz.
PHONES jack (J492)
2. Adjust L802 so that modulation distortion may become the
best in the vicinity of the maximum value where the tuner out
level becomes –15 dBuV or more.
digital voltmeter
FM AUTO STOP CHECK
SET
Reading on Digital Voltmeter
Procedure :
1.45 ± 0.3 V
1. Turn the power on.
7.7 ± 0.5 V
2. Input the following signal from Signal Generator to FM an-
tenna input directly.
Carrier frequency : A = 87.5 MHz, B = 98 MHz, C = 108 MHz
Deviation
Reading on Digital Voltmeter
Modulation
1.45 ± 0.3 V
ANT input
7.2 ± 0.5 V
Note: Please use 75 ohm "coaxial cable" to connect SG and the set. You
cannot use video cable for checking.
Please use SG whose output impedance is 75 ohm.
3. Set to FM tuner function and scan the input FM signal with
automatic scanning.
530 kHz
4. Confi rm that input Frequency of A, B and C detected and auto-
matic scanning stops.
The stop of automatic scanning means "The station signal is re-
ceived in good condition".
531 kHz
23 23
Reading on Digital
Frequency Display
Voltmeter
87.5 kHz 1.75 ± 0.1 V
108 kHz 6.2 ± 0.5 V
FM TRACKING ADJUSTMENT
Adjust for a minimum reading on level meter
L804 98 MHz
MAIN board
IC801 pin
(TUNER OUT L-ch)
MAIN board
CN801 pin
level meter
+
set
–
MAIN board
JW801 (TUNER-GND)
MAIN board
CN801 pin
generator
+
75 Ω
: 75 kHz
: 1 kHz
: 35 dBu (EMF)
HCD-EC69i/EC79i/EC99i
Ver. 1.1
Adjustment Location and Connecting Points:
– MAIN Board (Component Side) –
L802
FM Detector
Adjustment
L803
FM Frequency
L804
Coverage
FM Tracking
Adjustment
Adjustment
L805
AM Tracking
Adjustment
– MAIN Board (Conductor Side) –
IC801 pin
(TUNER VT)
3
CN801
36 19
1
1 18
IC801
JW801
(TUNER-GND)
IC801 pin
(TUNER OUT L-ch)