Yamaha YDO-323 Service Manual page 6

YDP-323
5. Circuit Boards & Assemblies (Main Unit)
(Time required: About 3 minutes each)
5-1 Remove the top board assembly. (See procedure 3)
5-2 Each circuit board and assembly can be removed by
removing its fixing screws as listed below.
Circuit board and Assembly
DM
MAEQ
PS Cover Assembly
Power Supply Unit
D-JACK Assembly
Speaker L
Speaker R
Speaker L
[S07A]
6. PS Circuit Board, Power Transformer
(Time required: About 5 minutes)
6-1 Remove the top board assembly. (See procedure 3)
6-2 Remove the power supply unit. (See procedure 5)
6-3 Remove the three (3) screws marked [6], the two (2)
screws marked [7A] and the two (2) screws marked
[1]. The PS circuit board can then be removed from
the AC inlet plate. (Fig. 5)
6-4 Power Transformer
Using the soldering iron, remove the seventeen
soldered place of the power transformer on the PS
circuit board. The power transformer can then be
removed from the PS circuit board. (Fig. 5-1)
* While soldering, be careful not to apply too much heat.
It might cause peeling off the land pattern.
6
Ref. No.
S12A Bind Head Tapping Screw-B 3.0X6 MFZN2W3 (WE936300)
S12B Bind Head Tapping Screw-B 3.0X6 MFZN2W3 (WE936300)
103A Bind Head Tapping Screw-1 3.5X12 MFZN2W3 (WE970900)
103B Bind Head Tapping Screw-1 3.5X12 MFZN2W3 (WE970900)
S13A Bind Head Tapping Screw-1 3.5X12 MFZN2W3 (WE970900)
S07A Truss Head Tapping Screw-1 4.0X16 MFZN2Y (WE965700)
S07B Truss Head Tapping Screw-1 4.0X16 MFZN2Y (WE965700)
D-JACK assembly
[S13A] [S12A]
DM DM
[S12A] [S12B]
Screw
Power supply assembly
[S12B] [103A]
MAEQ MAEQ
[103A]
Fig. 4
Power Supply Unit
●
AC inlet plate
[6]
[6]
Power transformer
[1]: Bind Head Tapping Screw-B 3.0X10 MFZN2B3 (WE972200)
[6]: Bind Head Tapping Screw-B 3.0X12 MFZN2W3 (WE987400)
[7A]: Bind Head Tapping Screw-B 4.0X10 MFZN2B3 (WE972300)
Speaker R
[103B] [103A] [S07B]
PS cover assembly
[7A]
Fig. 5
QTY Fig.
4 4
6 4
5 4
3 4
4 4
4 4
4 4
[S07B]
[6]
PS
[1]