Sony HCD-EC55 Service Manual page 27

TUNER SECTION
[AM]
Setting:
FUNCTION: TUNER
TUNER/BAND button: AM
loop antenna A loop antenna B
AM RF signal
generator
30% amplitude
modulation by
400 Hz signal
MAIN board
Output level: 54 dBuV ANTENNA
CN801 pin 12
[FM]
Setting:
FUNCTION: TUNER
TUNER/BAND button: FM
FM RF signal
generator
0.01 µF
MAIN board
75kHz frequency
ANTENNA
deviation by 1K Hz
CN801 pin 2
signal
Output level: as low as possible
(8dBuV)
MAIN board
TP (TUNER VT)
• Repeat the procedures in each adjustment several times.
0 dB=1 µV
60 cm
level meter
32 Ω
+
set
–
JACK board
PHONES jack (J402)
MAIN board
level meter
ANTENNA
CN801 pin 3
32 Ω
+
set
–
JACK board
PHONES jack (J402)
digital voltmeter
100 k Ω
HCD-EC55/EC77/GX99
AM FREQUENCY COVERAGE ADJUSTMENT
(US, Canadian, Australian models)
Adjustment Part Frequency Display Reading on Digital Voltmeter
L801 530 kHz
Confirmation 1,710 kHz
AM FREQUENCY COVERAGE ADJUSTMENT (Other models)
Adjustment Part Frequency Display Reading on Digital Voltmeter
L801 531 kHz
Confirmation 1,602 kHz
AM TRACKING ADJUSTMENT (US, Canadian, Australian models)
Adjust for a maximum reading on level meter
L805
AM TRACKING ADJUSTMENT (Other models)
Adjust for a maximum reading on level meter
L805
FM FREQUENCY COVERAGE ADJUSTMENT
Adjustment Part Frequency Display
L803 87.5 kHz
Confirmation 108 kHz
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L804
Adjustment Location: MAIN board (See page 28).
[FM DETECTOR ADJUSTMENT]
Setting:
FUNCTION: TUNER
TUNER/BAND button: FM
FM RF signal
generator
MAIN board
Carrier frequency: 98MHz
ANTENNA
Modulation:
CN801 pin 2
deviation by FM 75 kHz
Output level: 60 dBuV
1. Tune the set to 98 MHz.
2. Adjust L802 so that modulation distortion may become the
best in the vicinity of the maximum value where the tuner out
level becomes –15dBuV or more.
Ver. 1.1
1.5 ± 0.1 V
8 ± 0.5 V
1.5 ± 0.1 V
7.2 ± 0.5 V
530 kHz
531 kHz
Reading on Digital Voltmeter
1.75 ± 0.1 V
6.2 ± 0.5 V
98 MHz
MAIN board
IC801 pin qs
MAIN board
(TUNER OUT L-ch)
ANTENNA
CN801 pin 3
level meter
+
set
–
MAIN board
TP(TUNER-GND)
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