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

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 

LES  COMPOSANTS  IDENTIFIÉS  PAR  UNE  MARQUE  0  SUR  
LES  DIAGRAMMES  SCHÉMATIQUES  ET  LA  LISTE  DES  
PIÈCES  SONT  CRITIQUES  POUR  LA  SÉCURITÉ  DE  FONC-
TIONNEMENT.  NE  REMPLACER  CES  COMPOSANTS  QUE  
PAR  DES  PIÈCES  SONY  DONT  LES  NUMÉROS  SONT  DON-
NÉS  DANS  CE  MANUEL  OU  DANS  LES  SUPPLÉMENTS  
PUBLIÉS  PAR  SONY.

 .............................................  

3

2-1. Disassembly 

Flow 

...........................................................   5

2-2. Rear 

Panel 

.......................................................................   5

2-3.  FRONT LED Board, Top Panel Assy .............................   6
2-4.  Top Plate Block, Fuse (F900) .........................................   7
2-5. POWER 

Board 

................................................................   7

2-6.  Power Cord (AC1) ..........................................................   8
2-7. Sub 

AMP 

Block 

..............................................................   9

2-8.  SUB MAIN Board ..........................................................   9
2-9.  Bottom Panel Block ........................................................   10
2-10.  Loudspeaker (13 cm) (SP100) ........................................   11

3-1. Block 

Diagram 

................................................................  13

3-2.  Schematic Diagram - MAIN Section - ...........................   15
3-3.  Printed Wiring Board - MAIN Section (1/2) - ................   16
3-4.  Printed Wiring Boards - MAIN Section (2/2) - ..............   17
3-5.  Printed Wiring Board - POWER Board - ........................   18
3-6.  Schematic Diagram - POWER Board - ..........................   19

4-1. Overall 

Section 

...............................................................  24

4-2. Sub 

AMP 

Section 

............................................................  25

4-3.  Subwoofer Cabinet Section ............................................   26

 ..............................   27

UNLEADED  SOLDER
Boards requiring use of unleaded solder are printed with the lead-
free mark (LF) indicating the solder contains no lead.
(Caution:  Some printed circuit boards may not come printed with 

the lead free mark due to their particular size)

Unleaded solder has the following characteristics.
•  Unleaded solder melts at a temperature about 40 °C higher 

than ordinary solder.

 

Ordinary soldering irons can be used but the iron tip has to be 
applied to the solder joint for a slightly longer time.

 

Soldering irons using a temperature regulator should be set to 
about 350 °C.
Caution: The printed pattern (copper foil) may peel away if 

the heated tip is applied for too long, so be careful!

• Strong 

viscosity

 

Unleaded solder is more viscous (sticky, less prone to fl ow) 
than ordinary solder so use caution not to let solder bridges 
occur such as on IC pins, etc.

•  Usable with ordinary solder
 

It is best to use only unleaded solder but unleaded solder may 
also be added to ordinary solder.

ADVANCE  PREPARATION  WHEN  CONFIRMING  OP-
ERATION
All of the units included in the HT-CT260/260HP (SA-WCT260/
SA-CT260/EZW-RT50) are required to confi rming operation of 
the main unit. Check in advance that you have all of the units.

NOTE  OF  REPLACING  THE  IC104  ON  THE  SUB  MAIN  
BOARD  AND  THE  COMPLETE  SUB  MAIN  BOARD
When IC104 on the SUB MAIN board and the complete SUB 
MAIN board are replaced, it is necessary to spread the compound  
between the SUB MAIN board and the heat sink.

Part No.   

Remarks

J-2501-221-A 

THERMAL COMPOUND (G747)

Spread the compound referring to the fi gure below.

CAPACITOR  ELECTRICAL  DISCHARGE  PROCESSING 
When checking the board, for the electric shock prevention, con-
nect the resistors to both ends of respective capacitor (C935 or 
C936) to discharge the capacitor (C935 or C936).

:/2 W

MODEL  IDENTIFICATION
Distinguish by model number label stuck on the rear side of a main unit.

SA-WCT260 UC2

4-434-526-0s

SA-WCT260 CEL

4-434-528-0s

SA-WCT260 CEK

4-438-046-0s

SA-WCT260 SP1

4-438-047-0s

SA-WCT260 RU3

4-438-049-0s

SA-WCT260 AU1

4-447-896-0s

SA-WCT260 BR1

4-447-897-0s

•  This set can be disassembled in the order shown below.

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

1 two screws

u 8)

1 two screws

u 8)

3 Pull out the power code.

2 Remove the rear panel in 

4 rear panel