Yamaha GX-505 Service Manual page 55

A B
SCHEMATIC DIAGRAM (GX-505/GX-505VCD MAIN)
1
0
0
-12.6
-27.4
-12.6
-26.9 -51.0
-12.0 -23.6
2
REGULATOR
P62 K-2
P63 K-2
12.5 23.4 12.5 23.3
13.0
13.0
13.0
13.0
3
0
0
P64 K-6
P65 K-6
POWER AMP
P64 K-4
4
P65 K-4
-0.1
-0.1
MUTING
0
-5.9
5
(0.7)
0
0
(0.7)
-5.9
0
-0.1
-0.1
6
7
8
C D E
REGULATOR
23.5
51.0
-0.8
50.7
15.4
0
0
0.6
0
0
0
50.4
0
0
0
50.5
0 0
0
-15.7
-23.7
IC201 : STK496-420Y
2 Channel AF Power Amp
TR31
17
D6
R4
R14
TR1 TR2 TR14 TR13
D7
TR6 TR9 TR21
TR11 TR23
C2 C4
R2 C1 C3 R12
18
TR20
R19
TR4 R9 TR16
TR3 R5 R15 TR15
TR12 TR24
19 TR8
R6 R16
20
TR10 TR22
TR19
TR7
TR5
TR17
D1 R7 R17
R3
R8 R18
R13
R51
12 13 16 10 14 15 11 21 22 9
F G
51.0
-51.0
POWER
PROTECTION
SUPPLY
4.9
12.4
23.5
11.7
0
4.9 -23.7
0
12.3
0 0
0
11.3
0
-0.8
-23.6
-22.9
-23.7
R31 1
3
COMPARATOR
5
D35
D33
D31
4
2
SUB
D32
7
D34
D36
TR32 6
COMPARATOR
R32
8
H I
CIRCUIT CHANGES BY MARKET. O : USED X : NOT USED
AC6.1
AC10.4
AC37.8
AC79.5
SUB
POWER SUPPLY
13.4
0 13.4
0
0.7
AC13.5
0 0
P64 K-5
P65 K-5
* All voltage are measured with a 10M Ω /V DC electric volt meter.
* Components having special characteristics are marked Z and
* Schematic diagram is subject to change without notice.
J K
GX-505/GX-505VCD
must be replaced with parts having specifications equal to those
originally installed.
68