Sony Icf-c470 - fm/am wide User manual

MICROFILM

SERVICE MANUAL

ICF-C470

FM/AM CLOCK RADIO

ICF-C470L

FM/MW/LW 3 BAND CLOCK RADIO

US Model

Canadian Model

E Model

Australian Model

ICF-C470

AEP Model

ICF-C470/C470L

UK Model

ICF-C470L

SPECIFICATIONS

ICF-C470/C470L

Photo: ICF-C470

Ver 1.1 1999. 06

With SUPPLEMENT 1

(9-926-981-81)

– 2 –

TABLE OF CONTENTS

1. GENERAL ................................................................... 3

2. DISASSEMBLY ......................................................... 4

3. DIAL POINTER SETTING..................................... 5

4. POWER CORD SETTING ..................................... 6

5. ELECTRICAL ADJUSTMENTS.......................... 7

6. DIAGRAMS

6-1. Block Diagram ................................................................ 9

6-2. Printed Wiring Boards (ICF-C470) ................................ 11

6-3. Schematic Diagram (ICF-C470)..................................... 13

6-4. Printed Wiring Boards (ICF-C470L).............................. 15

6-5. Schematic Diagram (ICF-C470L) .................................. 17

7. EXPLODED VIEWS ................................................ 20

8. ELECTRICAL PARTS LIST ............................... 22

ATTENTION AU COMPOSANT AYANT RAPPORT

À LA SÉCURITÉ!

LES COMPOSANTS IDENTIFIÉS PAR UNE MARQUE !

SUR LES DIAGRAMMES SCHÉMATIQUES ET LA LISTE

DES PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ

DE FONCTIONNEMENT. NE REMPLACER CES COM-

POSANTS QUE PAR DES PIÈCES SONY DONT LES

NUMÉROS SONT DONNÉS DANS CE MANUEL OU

DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.

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.

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.

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

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 CHECK-OUT

After correcting the original service problem, perform the follow-

ing 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

TheAC 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.

1. A commercial leakage tester, such as the Simpson 229 or RCA

WT-540A. Follow the manufacturers’instructions to use these

instruments.

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 voltmeter. The “limit” indica-

tion is 0.75 V, so analog meters must have an accurate low-

voltage scale. The Simpson 250 and Sanwa SH-63Trd are ex-

amples of a passive VOM that is suitable. Nearly all battery

operated digital multimeters that have a 2VAC range are suit-

able. (See Fig. A)

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

1.5 k

Ω

0.15

FAC

voltmeter

(0.75 V)

To Exposed Metal

Parts on Set

Earth Ground

– 3 –

SECTION 1

GENERAL This section is extracted from

instruction manual.

– 4 –

CABINET (LOWER)

MAIN BLOCK

Note: Follow the disassembly procedure in the numerical order given.

SECTION 2

DISASSEMBLY

five screws

(P3

14)

two claws

cabinet (lower

)

power transformer

buzzer board

two claws

three claws

for chassis

three claws

for PWB

main block

Break the soldering

of speaker lead.

– 5 –

SECTION 3

DIAL POINTER SETTING

Install the MAIN board.

Turn VR1 to the

arrow

direction fully.

Turn shaft of CV1 to the

arrow

direction fully.

– BOTTOMVIEW –

Turn the knob (VOL) to the

arrow

direction fully.

Turn the knob (tuning) to the

arrow

direction fully.

dial pointer

Note: Follow the assembly procedure in the numerical order given.

– 6 –

SECTION 4

POWER CORD SETTING

lower cabinet

power cord

FM antenna

Set the power cord as illustrated below,

then install the lower cabinet.