Sony ICF-C492 Service Manual ▷ View online
ICF-C492
5
3-3. CABINET (REAR) SUB ASSY
3-4. MAIN BOARD
6
two screws (B2.6)
(P TAPPING)
(P TAPPING)
7
two transformer retainer brackets
8
power board block
9
two screws (B2.6)
(PWH TAPPING)
(PWH TAPPING)
0
retainer PWB
BUZZER board
qs
Remove two solders.
qd
cabinet (rear) sub assy
knob (timer set)
S102
qa
1
screw (B2.6)
(P TAPPING)
(P TAPPING)
4
flexible flat cable (9 core)
(CN102)
(CN102)
5
harness from speaker
(CN2)
(CN2)
3
harness from POWER board
(CN302)
(CN302)
2
Note: When install the cabinet (rear) sub assy,
adjust the knob (timer set) and S102.
1
Remove the solder.
2
four claws
4
flexible flat cable (18 core)
5
LED indicator element
6
two screws
8
MAIN board
7
claw
3
ICF-C492
6
3-5. POINTER SETTING
knob (tuning)
pointer
Note: When install the pointer, fully turn
the knob (tuning) in the direction
of the arrow, and set the pointer as shown
in figure.
of the arrow, and set the pointer as shown
in figure.
7
ICF-C492
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter
T1
455 kHz
0 dB=1
µ
V
[AM]
Setting:
BAND: switch AM
BAND: switch AM
[FM]
Setting:
BAND: switch FM
BAND: switch FM
• Repeat the procedures in each adjustment several times, and
the frequency coverage and tracking adjustments should be
finally done by the trimmer capacitors.
finally done by the trimmer capacitors.
• Remove FM antenna in FM adjustments.
AM RF signal
generator
30% amplitude
modulation by
400 Hz signal
Output level: as low as possible
modulation by
400 Hz signal
Output level: as low as possible
Put the lead-wire
antenna close to
the set.
antenna close to
the set.
+
–
–
level meter
set
8
Ω
MAIN board
CN2 pin
CN2 pin
2
MAIN board
CN2 pin
CN2 pin
1
FM RF signal
generator
22.5 kHz frequency
deviation by 400 Hz
signal
Output level: as low as possible
deviation by 400 Hz
signal
Output level: as low as possible
+
–
–
level meter
MAIN board
CN2 pin
CN2 pin
2
MAIN board
CN2 pin
CN2 pin
1
set
8
Ω
0.01
µ
F
MAIN board
TP (FM ANT)
TP (FM ANT)
SECTION 4
ELECTRICAL ADJUSTMENTS
Adjustment Location: MAIN board (See page 8)
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter
L4
515 kHz
CT1-4
1,750 kHz
FM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter
L3
86.5 MHz
CT1-3
109.5 MHz
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L1
600 kHz
CT1-1
1,400 kHz
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L2
86.5 MHz
CT1-2
109.5 MHz
8
ICF-C492
Adjustment Location:
AM Tracking Adjustment
FM Tracking Adjustment
FM Frequency Coverage Adjustment
AM Frequency Coverage Adjustment
T1
AM IF Adjustment
CT1-1
L1
CT1-4
L4
CT1-3
L3
L2
CT1-2
– MAIN BOARD (Component Side) –
– MAIN BOARD (Conductor Side) –
S1
BAND
AM
Y
FM
CN2
1
2
TP (FM ANT)
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