Yamaha YST-SW225 Service Manual page 12

A B
YST-SW225
I PRINTED CIRCUIT BOARD (Foil side) Lead Free Solder Used
1
GY OR
2
BE
OR
3
GY
WH
4
5
AUT
PWS
VCC
+V1
E
6
R72
add 10 kohms
7 CONFIRMATION OF
AUTO STANDBY OPERATION
12
C D
MAIN (5) P. C. B.
POWER
ON OFF
MAIN (2) P. C. B.
R, L models
MAIN (9) P. C. B.
BR BE YE
AUTO
STANDBY
GY
OFF
LOW
HIGH
E F G
MAIN (7) P. C. B. MAIN (6) P. C. B.
BE
WH
MAIN (7) P. C. B. MAIN (6) P. C. B.
BE
BE
GY
BR
YE
WH
H I J
• Semiconductor Location
Ref. no. Location Ref. no. Location Ref. no. Location
D1 C4 D27 J5 IC7
D4 B5 D28 J5 IC8
D5 B4 D29 J2 Q1
D18 H6 D30 J2 Q2
D21 I6 D31 J2 Q3
D22 I5 D32 H4 Q9
D23 I2 D33 I3 Q22
D24 I5 D34 I4 Q23
D25 I2 D35 I3 Q24A
D26 J5 IC6 B6 Q24C
WH RE
+B1
DR+
TR-B
DR-
OUT
-B1
AYST
+15
E
POW
G
AC
+B
SG
-B
MAIN (10) P. C. B.
K
Ref. no. Location
B6 Q25 J4
B5 Q26 J3
B5 Q28 H4
B5 Q29 I3
B5 Q30 I4
B6 Q31 I4
J3 Q32 J5
I4 Q33 J2
J2 Q34 I4
J5