Servicing Notes - Sony SA-WCT290 Service Manual

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)
: LEAD FREE MARK
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.
NOTE OF PERFORMING THE OPERATION CHECK IN
THE STATE THAT HEAT SINK WAS REMOVED
When performing the operation check in the state that this unit was
disassembled, it is possible to perform the operation check in the
state that heat sink was removed. But don't perform the operation
check in the long time, and perform the operation check in the
volume state as low as possible.
CAPACITOR ELECTRICAL DISCHARGE PROCESSING
When checking the board, for the electric shock prevention, con-
nect the resistors to both ends of capacitors to discharge the capaci-
tor as shown in the fi gure below.
Note 1: When the connector
REGULATOR 3L411L board (US, CND) or SWITCHING
REGULATOR 3L411W board (Except US, CND, E12) or
SWITCHING REGULATOR 3L411W-1 board (E12) to the SUB
MAIN board is disconnected before discharging, completely
fi nish discharging both boards, and then reconnect the connector.
If discharging is not complete, sparking may occur when
connecting the connector and cause a blown fuse.
Note 2: Be sure to discharge using a resistor of 800 Ω or higher.
(Do not discharge with a 0 Ω resistor)
Discharging at a point where excessive electric current fl ows
through a fuse may cause the fuse to blow.
– SUB MAIN Board (Component Side) –
SECTION 1

SERVICING NOTES

that connects the SWITCHING
800 / 800 /
2 W 2 W
C8138
C8140
– SWITCHING REGULATOR 3L411L Board
(US, CND) (Conductor Side) –
– SWITCHING REGULATOR 3L411W Board
(Except US, CND, E12) (Conductor Side) –
– SWITCHING REGULATOR 3L411W-1 Board
(E12) (Conductor Side) –
MODEL IDENTIFICATION
Distinguish by Part No. and destination code on the rear side of
the subwoofer.
– Rear view –
MODEL NUMBER LABEL
Model
SA-WCT290 (Black): US, CND
SA-WCT290 (Black): AEP
SA-WCT290 (Black): UK
SA-WCT290 (Black): RU
SA-WCT290 (Black): E12
SA-WCT290 (Black): E3
SA-WCT290 (Black): EA
SA-WCT290 (Black): SP
SA-WCT290 (Black): AUS
SA-WCT290 (Black): TH
SA-WCT290 (Black): LA9
SA-WCT291 : AEP
SA-WCT291 : UK
SA-WCT291 : RU
SA-WCT290 (White): EA
SA-WCT290 (White): SP
SA-WCT290 (White): TH
• Abbreviation
AUS : Australian model
CND : Canadian model
E3 : 240 V AC area in E model
E12 : 220-240 V AC area in E model
EA : Saudi Arabia model
LA9 : Latin-American model
RU : Russian Model
SP : Singapore model
TH : Thai model
SA-WCT290/WCT291
C201
800 /2 W
Destination code
Part No.
Part No.
4-688-018-0[]
4-688-018-1[]
4-688-018-2[]
4-688-018-3[]
4-688-018-4[]
4-688-018-5[]
4-688-018-6[]
4-688-018-7[]
4-688-018-9[]
4-688-019-0[]
4-688-019-2[]
4-688-020-0[]
4-688-020-1[]
4-688-020-2[]
4-693-270-2[]
4-693-270-3[]
4-693-270-5[]
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