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ICF-C290
FM/AM CLOCK RADIO
ICF-C290L
FM/LW CLOCK RADIO
MICROFILM
AEP Model
ICF-C290/C290L
UK Model
E Model
Australian Model
ICF-C290
SPECIFICATIONS
SERVICE MANUAL
ICF-C290/C290L
Photo: ICF-C290
Ver 1.1 1998. 10
With SUPPLEMENT 1
(9-925-745-81)


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Notes on chip component replacement
· Never reuse a disconnected chip component.
· Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK
! OR DOTTED
LINE WITH MARK
! ON THE SCHEMATIC DIAGRAMS
AND IN THE PARTS LIST ARE CRITICAL TO SAFE
OPERATION. REPLACE THESE COMPONENTS WITH
SONY PARTS WHOSE PART NUMBERS APPEAR AS
SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-
LISHED BY SONY.
CF2
CF3
mark
Mark
Center frequency
red
10.70 MHz
blue
10.67 MHz
orange
10.73 MHz
black
10.64 MHz
white
10.76 MHz
HOW TO CHANGED THE CERAMIC FILTERS
This model is used two ceramic filters of CF2 and CF3.
You must used same type of color marked ceramic filters in order
to meet same specifications.
Therefore, the ceramic filter must changed two pieces together
since it's supply two pieces in one package as a spare parts.
SERVICING NOTES


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SECTION 1
GENERAL
This section is extracted from
instruction manual.


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Set the power cord as illustrated below, then install the lower cabinet.
SETTING THE POWER CORD
SECTION 2
SETTING
KNOB SETTING
7 claws
5 MAIN board
3 Turn shaft of CV1 to the
arrow
A direction fully.
4 Turn RV1 to the arrow B
direction fully.
6 claw
2 Turn the knob (VOL) to the
arrow
B direction fully.
1 Turn the knob (tuning) to the
arrow
A direction fully.
A
B
lower cabinet
power cord


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(
): Italian model
FM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter.
L3
86.5 MHz (87.35 MHz)
CT3
109.5 MHz (108.25 MHz)
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
CT2
109.5 MHz (108.25 MHz)
AM FREQUENCY COVERAGE ADJUSTMENT (C290)
Adjust for a maximum reading on level meter.
L4
520 kHz (516.5 kHZ)
CT4
1,650 kHz (1,631.5 kHz)
AM TRACKING ADJUSTMENT (C290)
Adjust for a maximum reading on level meter.
L1
600 kHz
CT1
1,400 kHz
LW FREQUENCY COVERAGE ADJUSTMENT (C290L)
Adjust for a maximum reading on level meter.
L4
145 kHz
CT6
265 kHz
LW TRACKING ADJUSTMENT (C290L)
Adjust for a maximum reading on level meter.
L1
160 kHz
CT5
240 kHz
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T1
455 kHz
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SECTION 3
ELECTRICAL ADJUSTMENTS
FM SECTION
Setting:
BAND switch: FM
AM SECTION
Setting:
BAND switch: AM/LW
· Repeat the procedures in each adjustment several times, and
the frequency coverage and tracking adjustments should be fi-
nally done by the trimmer capacitors.
Adjustment Location: MAIN board (Conductor Side)
FM RF signal
generator
400 Hz, 30% FM modulation
frequency deviation
± 22.5 kHz
Output level: as low as possible
0.01
µF
set
lead antenna
input terminal
AM RF signal
generator
400 Hz, 30%
AM modulation
Output level: as low as possible
Put the lead-wire
antenna close to
the set.
level meter
set
speaker terminal
8
+
­
IC1
CT6
LW FREQUENCY
COVERAGE
AM FREQUENCY
COVERAGE
FM TRACKING
AM TRACKING
LW TRACKING
AM IF
FM FREQUENCY
COVERAGE
L4
L3
L3
CV1
CT2
CT5
L1
T1
CT1
CT4
CT3