Sony icf c 250 service manual

Page 1

/CF-C2508 Y

TIME SET-M button ALARM button

TIME SET CLOCK bum," DREAM BAR SNOOZE/SLEEP E Model

FUNCTION selector

OFF button (US model) _
3230 ON REPEAT ALARM/SLEEP OFF button [CF 0250
ALARM (RADIO (AEP, IT, E model)

BUZZER)

Band (FM/AM) selector
VOL (volume) control

TUNING control
Pillow speaker

Eeaphonejack (left side) Photo: ICFCZ5OSY

SPECIFICATIONS FEATURES
Frequency range 0 Electronic digital alarm clock and sleep timer are combined.
FM AM
us model 87 6710: 53071 MHZ 0 Two wake-up modes available: radio or buzzer alarm.
AEP E model 37571075,: kgmkm . DREAM BAR SNOOZE/SLEEP OFF bar (us model),
IT model 87.5-108MH1 526.5e1,6os.5kHz REPEART ALARM/SLEEP OFF bar (AEP' 'T' E "OdED'
operable with a feather-light touch,
Amen EMIBA? aigsizecgégggiflga oifers two iunctions: snooze alarm and sleep timer turn off.
Speaker Appmrjés MT/n inches) dia, - Power back~up function to keep the clock operating during a
Output Earphone jack(minijack) power interruption, using an optional 6F22 battery.
Power output 100 mW (at 10% harmonic
distortion)
Power requirements >
120 V AC, 60 Hz (US modeII
220v Ac, 50H: IAEP, IT, E model)
For the power backup
Iunction: 9 V DC, one 6F22
battery
Battery life Approx. 80 hours, using Sony
battery SOOEP (U)
Dimensions Approx. 181.5 x 59 x 144 mm
(w/h/d)
(77. x 25/. x 5% inches)
incl. projecting parts and controls SAFETY-RELATED COMPONENT WARNINGI!
. 20 1 lb
we'gh gagging; 3) COMPONENTS IDENTIFIED 3v MARK A on DOTTED
Accessory supplied Pillow Speaker (1) (rcpczsosy) LINE WITH MARK A ON THE SCHEMATIC DIAGRAMS
AND IN THE PARTS LIST ARE CRITICAL TO SAFE
DESIGN ano specifications subjecttochange OPERATION. REPLACE THESE COMPONENTS WITH
"hm ce' sowv PARTS WHOSE PART NUMBERS APPEAR AS
us i AEP IT E d I SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-
"°e ' ' "° 9 LISHED BY soNv.
12-hour: system 24-hour system
AM 12:00 = midnight 0:00 = midnight
PM I2100 = noon 12:00 = noon

FM/AM DIGITAL CHICK RADIO

ONY;

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lCF-C250/C25OSY

SAFETY CHECK-OUT

After correcting the original service problem,
perform the following safety check before releasing
the set to the customer:

Check the antenna terminals, metal trim, metallized
knobs, screws, and all other exposed metal parts for
AC leakage. Check leakage as described below.

LEAKAGE TEST

The AC leakage from any exposed metal part to
earth ground and from all exposed metal parts to any
exposed metal part having a return to chassis, must
not exceed 0.5 mA (500 microampers). Leakage
current can be measured by any one of three
methods.

I. A commercial leakage tester, such as the
Simpson 229 or RCA WT-540A. Follow the
manufacturers instructions to use these instru-
ments.

2. A battery-operated AC milliammeter. The Data

Precision 245 digital multimeter is suitable for
this job

3. Measuring the voltage drop across a resistor by
means of a VOM or battery-operated AC volt-
meter. The limit indication is 0.75 V, so
analog meters must have an accurate low-
voltage scale. The Simpson 250 and Sanwa
SH»63Trd are examples of a passive VOM that
is suitable. Nearly all battery operated digital
multimeters that have a 2 V AC range are
suitable. (See Fig. A)

To Exposed Metal
Part: on Set

AC
0.15uF g 1.5ksl / voltmeter
(0. 75 VI

'._J

7 Earth Ground

Fig. A. Using an AC voltmeter to check AC leakage.

SECTION 1
GENEML

1-1. MODEL IDENTIFICATION
-Model Number Label-
Carved on lower cabinet

S ONY.
FM/AM zsANDs

mu m: ICF-0250

US modal: AC: 120V 60Hz 5W
AEP, IT, E model: AC1220V ~ 50Hz 5W

1-2. MAIN BOARD REMOVAL

0 Turn TUNING knob fully clockwise.
9 Remove screw (+B 2.6x 5)
6 Release took,
0 Remove main board pressing down TUNING knob.
Note: When installing main board, align shaft of VOL knob
with a hole of adjustable resistor.

MAIN BOARD

adj ustab Ie
resistor