Sony SA-WCT290, Service Manual

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SA-WCT290/WCT291
3
SECTION 1
SERVICING NOTES
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 that connects the SWITCHING
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.
C8138
C8140
– SUB MAIN Board (Component Side) –
800
:
/
2 W
800
:
/
2 W
C201
800 /2 W
– 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.
MODEL NUMBER LABEL
– Rear view –
Part No.
Destination code
Model Part No.
SA-WCT290 (Black): US, CND 4-688-018-0
[]
SA-WCT290 (Black): AEP 4-688-018-1
[]
SA-WCT290 (Black): UK 4-688-018-2
[]
SA-WCT290 (Black): RU 4-688-018-3
[]
SA-WCT290 (Black): E12 4-688-018-4
[]
SA-WCT290 (Black): E3 4-688-018-5
[]
SA-WCT290 (Black): EA 4-688-018-6
[]
SA-WCT290 (Black): SP 4-688-018-7
[]
SA-WCT290 (Black): AUS 4-688-018-9
[]
SA-WCT290 (Black): TH 4-688-019-0
[]
SA-WCT290 (Black): LA9 4-688-019-2
[]
SA-WCT291 : AEP 4-688-020-0
[]
SA-WCT291 : UK 4-688-020-1
[]
SA-WCT291 : RU 4-688-020-2
[]
SA-WCT290 (White): EA 4-693-270-2
[]
SA-WCT290 (White): SP 4-693-270-3
[]
SA-WCT290 (White): TH 4-693-270-5
[]
• 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
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