Sony ICFC-763 Service manual

ICF-C763/C763L

SERVICE MANUAL

Ver 1.0 2004.05

SPECIFICATIONS

Time display

UK, North and South America 12-hour system
Other countries/regions 24-hour system

Frequency range

Model for North and South America

Band ICF-C763 Channel step

FM 87.5 - 108 MHz 0.1 MHz
AM 530 - 1 710 kHz 10 kHz

Model for other countries/Regions

Band ICF-C763 ICF-C763L Channel step

FM
AM (MW) 531 - 1 602 kHz 531 - 1 602 kHz
LW

Speaker

Approx. 5.7 cm (2 1/4 inches) dia. 4 Ω

87.5 - 108 MHz 87.5 - 108 MHz

— 153 - 279 kHz

0.05 MHz
9 kHz
3 kHz

US Model

Canadian Model

ICF-C763

AEP Model

ICF-C763/C763L

UK Model

ICF-C763L

Power requirements

North and South American model : 120 V AC, 60 Hz
Other model : 230 V AC, 50 Hz

Dimensions

Approx. 115.5 x 105 x 110.6 mm (w/h/d) (4 5/8 x 4 1/4 x 4 3/8 inches)
including projecting parts and controls

Mass

Approx. 665 g (1 lb 7.5 oz)
Approx. 675 g (1 lb 7.8 oz): ICF-C763L (UK model)
Approx. 600 g (1 lb 5.2 oz): ICF-C763 (North and South America model)

Design and specifications are subject to change without notice.

9-877-783-01

2004E02-1
© 2004.05

Power output

200 mW (at 10 % harmonic distortion)

ICF-763

FM/AM PLL SYNTHESIZED CLOCK RADIO

ICF-763L

FM/MW/LM PLL SYNTHESIZED CLOCK RADIO

Sony Corporation

Personal Audio Company
Published by Sony Engineering Corporation

ICF-C763/C763L

TABLE OF CONTENTS

Specifications ........................................................................... 1

1. GENERAL

Location and Function of Controls .................................... 3

2. ELECTRICAL ADJUSTMENTS............................. 4

3. DIAGRAMS

3-1.IC Block Diagrams ...................................................... 6

3-2. IC Pin Function Descriptions ..................................... 7

3-3. Printed Wiring Board – Main section –...................... 8

3-4. Schematic Diagram – Main section–.......................... 9

3-5. Printed Wiring Board – Contrd section – ................. 10

3-6. Schematic Diagram – Contrd section – ................... 11

3-7. Printed Wiring Board – Power section – .................. 12

3-8. Schematic Diagram – Power section – ..................... 12

4. EXPLODED VIEW

4-1.Cabinet (Upper) Section ............................................ 13

5. ELECTRICAL PARTS LIST................................... 14

SAFETY CHECK-OUT

After correcting the original service problem, perform the following
safety checks 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

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.

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” 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 2V AC range are suitable. (See
Fig. A)

• HOW TO CHANGE THE CERAMIC FILTER

This model is used two ceramic filters of CF2 and CF3.
You must use same type of color marked ceramic filters in
order to meet same specifications.
Therefore, the ceramic filter must change two pieces together
since it's supply two pieces in package as a spare parts.

mark

mark

Mark

no mark

CF2

CF3

blue

orange

black
white

SAFETY-RELATED COMPONENT WARNING!!

COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE WITH
MARK 0 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 PUBLISHED BY SONY.

Center

frequency

10.70MHz

10.67MHz

10.73MHz

10.64MHz

10.76MHz

To Exposed Metal
Parts on Set

0.15µF

1.5kΩ

Earth Ground

AC
voltmeter
(0.75V)

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

ATTENTION AU COMPOSANT AYANT RAPPORT

À LA SÉCURITÉ!!

LES COMPOSANTS IDENTIFIÉS P AR UNE MARQUE 0 SUR LES
DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES PIÈCES
SONT CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT .
NE REMPLACER CES COMPOSANTS QUE PAR DES PIÈCES
SONY DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL
OU DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.

2

LOCATION AND FUNCTION OF CONTROLS

P

U

S

H

O

P

E

N

SNOOZE/SLEEP OFF

The PRESET 3 button and VOLUME have a tactile dot.

BRIGHTNESS

TUNE/TIME SET

SECTION 1

GENERAL

ICF-C763/C763L

This section is extracted from
instruction manual.

NAP

FM12

MW

AM
LW
PM

D.S.T./

SLEEP

CLOCK

AB

SELECTPRESET

SNOOZE/

SLEEP OFF

RADIO

ENTER

RADIO

A

ALARM MODEALARM

B

SOUND

54321

12345

WAKE UP

PRESET

MHz kHz

AC power cord

RADIO

ON

SLEEP

NIGHT LIGHT MODE

OFF ON

PRESETOFF

BAND

STANDBY

VOLUME

3

ICF-C763/C763L

TUNER SECTION 0 dB = 1 µV

• AM Section

Setting:

BAND button: AM <MW and LW>

SECTION 2

ELECTRICAL ADJUSTMENTS

< > : ICF-C763L

• ICF-C763 [ ] : Italian model

AM IF ADJUSTMENT

Adjust for a maximum reading on level meter.

T1

450 kHz

AM RF signal
generator

Put the lead-wire
antenna close to
the set.

30% amplitude
modulation by
400 Hz signal

• FM Section

Setting:

BAND button:FM

FM RF signal
generator

TP (ANT)

0.01

µ

F

set

22.5 kHz frequency
deviation by 400 Hz signal
output level : as low as possible

• Connecting Level Meter (FM, AM<MW and LW>)

level meter

(range 0.5-5V AC)

32

SPK+

Ω

AM FREQUENCY COVERAGE

ADJUSTMENT

Frequency Display
Reading on Digital voltmeter 3.0 ± 0.1 V
Adjustment Part L4 <confirmation>

Adjust for a maximum reading on level meter.

L1 CT1

530 kHz [531kHz] 1.490 kHz [1.404kHz]

530 kHz [531 kHz]

AM TRACKING ADJUSTMENT

1,710 kHz

10.0 ± 1.0V[9.0 ± 1.0V]

[1,602 kHz]

• ICF-C763L

MW IF ADJUSTMENT

Adjust for a maximum reading on level meter.

T1

450 kHz

MW FREQUENCY COVERAGE

ADJUSTMENT

Frequency Display 531 kHz 1.602 kHz
Reading on Digital voltmeter
Adjustment Part L4 <confirmation>

Adjust for a maximum reading on level meter.

L1 CT1

621 kHz 1.404 kHz

LW FREQUENCY COVERAGE

Frequency Display 153 kHz 279 kHz
Reading on Digital voltmeter 2.3 ± 0.3 V 9.0 ± 0.1 V
Adjustment Part <confirmation> CT4

2.75 ± 0.1 V 9.0 ± 1.0 V

MW TRACKING ADJUSTMENT

ADJUSTMENT

• Connecting Digital Voltmeter (FM, AM <MW and LW>)

digital
voltmeter

100 kΩ

TP (VT)

• Repeat the procedures in each adjustment several times, and the
frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.

4

LW TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter.

L1 CT2

162 kHz 243 kHz

• ICF-C763/C763L

FM FREQUENCY COVERAGE

CONFIRMATION

Frequency Display 87.5 MHz 108 MHz
Reading on Digital voltmeter 3.2 ± 0.3 V 10.0 ± 1.5 V
Adjustment Part <confirmation> <confirmation>

FM TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter.

L2 CT3

87.5 MHz 108 MHz

Adjustment and Connect Location: See page 5.

e

JC1

C14

C44

C20

R8

R9

R6

C4

JW1

JW12

C22

C2

C8

C9

C30

C11

C10

JC1

C26

C28

C15

E

E B

E B C

E B C

C B

C B E

C B E

JC

C

R

JW4

R22

R14

C23

R15

C24

C29

L3

C33

C36

C34

C32

R3

C12

C13

JW9

R7

CT4

CT1

CT2 CT3

C43

D103

D104

C7:C763

JC7:C763L

C763

C763L

C763L

C763L

C6

JW8

C5
R5

C1

R2

R4

C3

D2

R18

R20

C40

R17

R16

C37

T1

CF1

C31

SPK+

C3

C39

R13

C27

R21

JC2

D3

L2

L4

BPF1 CF2

C25

US,CND

IT,UK

IT,AEP

JW110

JW3

R19

C41

R1

Q1

D4

Q4

Q6

Q7

Q2

D1

IC1

1

2

1

2

1

14

15

28

TP(ANT)

TP(VT)

Adjustment and Connect Location

MAIN BOARD (Component Side)

ICF-C763/C763L

L4 : AM (MW)
Frequency coverage
adjustment

CT4 : LW
Frequency coverag
adjustment

CT1 : AM (MW)
tracking
adjustment

T1 : AM (MW)
IF adjustment

L1 : LW tracking
adjustment

L2 : FM tracking
adjustment

CT3 : FM tracking
adjustment

L1 : AM (MW)
tracking
adjustment

CT2 : LW
tracking
adjustment

MAIN BOARD (Conductor Side) MAIN BOARD (Conductor Side)

SPK+

TP (VT)

TP (ANT)

5

ICF-C763/C763L

SECTION 3
DIAGRAMS

• Circuit Boards Location

Note:

• All capacitors are in µF unless otherwise noted. pF: µµF 50 WV or

less are not indicated except for electrolytics and tantalums.

• All resistors are in Ω and 1/

Note:

The components identi­fied by mark 0 or dotted
line with mark 0 are criti-
cal for safety.
Replace only with part
number specified.

• A : B+ Line.

• H : adjustment for repair.

•Voltages are dc with respect to ground under no-signal conditions.

no mark : FM
(): AM

•Voltages are taken with a VOM (Input impedance 10 MΩ).

Voltage variations may be noted due to normal production toler­ances.

• Signal path.

F : FM
f : AM

• Abbreviation

CND : Canadian model
IT : Itarian model

4

W or less unless otherwise specified.

Note:

Les composants identifiés par
une marque 0 sont critiques
pour la sécurité.
Ne les remplacer que par une
piéce portant le numéro
spécifié.

Note:

• X : parts extracted from the component side.

•

: Pattern from the side which enables seeing.

3-1. IC Block Diagrams

IC1 CXA1019M

GND

GND

AF OUT

Vcc

RIPPLE

FILTER

AF IN

DET OUT

AFC AGC

AFC AGC

IF GND

METER

N. C

FM IF IN

AM IF IN

FM/AM

BAND

SELECT

9

REG OUT

21222324252627

10

TUNING

FM RF

METER

11

1920

12

AM RF IN

N. C

18

FM IF

13

17

14

FM RF IN

FE GND

16

15

MIX OUT

30

1

GND

2829

AF POWER AMP

3

2

GND

4

NF

FM DISCRI

AM IF DET AGC

AM FE

FM

DISCRIMINATOR

FM FE

5

6

VOL

AM OSC

8

7

AFC

FM OSC

6