Sony str de 225 service manual

Page 2

General
System Tuner section; PLL quartz-locked
digital synthesizer system
Preamplifier section:
Low-noise NF type epualizer
Power amplifier section:
Pure-complimentary SEPP
Power 230 V AC. 50/60 Hz
requirements
We: _ STR-DE325: 195 W
5"an sm-szsz no w
AC outlets Switched 100 W
(except for the UK. model)
Dimensions 430 x 145 x 295 mm
Mass(Appmx.) STR-DESZS: 7.4 kg
STR-DHZS: 6.1 kg
Supplied FM wire aerial (l)
accessories AM loop aerial (1)
Remote controller (remote) (1)
Size AA (R6) batteries (2)
Scan adaptor (1)

Design and specifications are subject to change without notice.
Specifications indicamd are measured at 230 VAC, 50 Hz

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 pan 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
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-63Ird are examples of
a passive VOM that is suitable. Nearly all battery operated
digital multimeters that have :1 2V AC range are suitable. (See
Fig. A)

'IbExposedMetal
PartsonSet
AC
0.15%]: gum m
5' 5301th

F:g.A. UsinganAC whnelertodmdrAC/eakage.

TABLE OF CONTENTS

1. GENERAL ............................................................... 3
2, TEST MODE ...................... 4
3 DIAGRAMS

3-1. Circuit Boards Location -
3-2. Block Diagram --------

3-3. Schematic Diagram -- Display Section -
3-4. Printed Wiring Boards - Display Section -
3»5. Schematic Diagram - Power Section -
3-6. Printed ering Boards - Power Section -
3-7. Printed Wiring Boards - Main Section -
3-8. Schematic Diagram - Main Section (1/3) --
3«9. Schematic Diagram - Main Section (2/3) --
3~ 10. Schematic Diagram - Main Section (3/3) -
3«11. IC Pin Function Description
3-12. IC Block Diagrams ~~~~~~~~~~~~~

4. EXPLODED VIEWS
4.1_ Front Panel Section .......................................................... 29
4.2_ Chassis Section ................................................................. 3o

5. ELECTRICAL PARTS LIST-~-

SAFETY-RELATED COMPONENT WARNINGII

COMPONENTS IDENTIFIED BY MARKAOR DOTI'ED LINEWITH
MARK A ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS
LIST ARE CRITICALTO SAFE OPERATION. REPLACE THESE
COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS
APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS
PUBLISHED BY SONY.

ATTENTION AU COMPOSANT AYANT RAPPORT
A LA SEcunrrEl

LES COMPOSANTS IDENTIFES PAH UNE MARGUE A sun LES
DIAGRAMMES SCHEMATIQUES El' LA LISTE DES PIECES SONT
cnmaues POUR LA sEcunITE DE FONCTIONNEMENT. NE
REMPLACEH CES COMPOSANTS QUE PAR DES PIESES SONY
DONT LEs NUME'nos SONT DONNEs DANS CE MANUEL ou
DANS LES SUPPEMENTS PUBLIES PAR SONY.

_2_