A
1
2
3
4
5
6
7
8
YST-MS50/YST-MS55D
B
C
D
E
F
G
H
I
J
K
24
IC3 : NJM4556AL
Dual Op-Amp
IC1,2,7,8 : UPC4570HA
Dual OP-Amp
IC6 : STK408-040E
3-channel AF Power Amp
■
SCHEMATIC DIAGRAM (YST-MS55D)
★
All voltages are measured with a 10M
Ω
/V DC electric volt meter.
★
Components having special characteristics are marked and
must be replaced with parts having specifications equal to those
originally installed.
★
Schematic diagram is subject to change without notice.
PIN CONNECTION DIAGRAM OF DIODES, TRANSISTORS AND IC’s.
NJM78M12FA
AN78M12F
2SA1015(O,Y)
2SC1815(Y,GR)
2SC2878(A,B)
2SC3792
1SS133
1SR139-400
HSS104TD
MTZJ3.9A
Anode
Cathode
D3SBA20
RBV-402
2SK304(E)
1
2
3
–
+
1
+
–
2
4
5
6
7
8
9
Vcc
Vo1 –Vin1 +Vin1 V
EE
+Vin2 –Vin2 Vo2 Vcc
1
2
3
–
+
+
–
4
5
6
8
9
OUT1
–IN1
+IN1
–Vcc
+IN2
=IN2
OUT2
+Vcc
NJM79M12FA
AN79M12F
NJM4556AL
UPC4570HA
STK408-040E
2SD2913(R,S)
M24C02-BN6
UPA1321PS
D
S
G
3
2 1
1.COMMON
2.INPUT
3.OUTPUT
3
2 1
1.COMMON
2.INPUT
3.OUTPUT
9
1
1
8
1
4
8
B
C
E
16
1
32
TO LEFT
SPEAKER
SATELLITE
MIDRANGE
Lch
TO
SUB
Wo.
VOLUME
SATELLITE
TWEETER
Lch
+
–
+
–
TO RIGHT
SPEAKER
POWER
VO
LT
A
G
E
SELECT
OR
(AUTO POWER)
SATELLITE
TWEETER
Rch
SATELLITE
MIDRANGE
Rch
TO
SUB
Wo.
USB
INPUT
TO RIGHT
SPEAKER
SUB
WOOFER
OUTPUT
BASS
(HEAD-
PHONE)
+
–
+
–
USB IN USE ONLY
0
0
0
-11.5
-1.5
0
0
0
12.0
12.0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
12.0
12.0
0
0
0
12.0
12.0
0
0
27.1
-11.5
0
-27.2
-11.5
-11.5
0
-11.5
0.2
0
0
0
0
-27.2
-0.2
-0.2
-0.1
-0.1
25.5
-25.6
0
0
27.1
-27.2
-27.2
0
2.8
2.8
2.8
24.0
3.4
2.8
2.8
2.8
2.8
0
0
1.4
2.8
0
1.4
2.8
0
1.4
0
0
0
0
0
0
2.8
2.8
0
0
2.8
2.8
0
1.4
1.3
0
0
0
0
0
0
11.4
12.0
11.4
10.7
12.0
10.1
0
0
0
12.0
0
0
0
0
0
0
12.0
0
0
0
-27.2
AC43.1
27.1
YST-MS55D
17
3
15
16
10
4
9
5
8
11
12
13
14
2
1
18
19
7
PT1
6
20
R22
R27
R29
R28
R23
D6
D4
C4
D5
D1
C5
R21
R25
R24
C6
D7
TR29
TR32
TR36
TR32
TR30
TR26
TR28
TR27
TR25
R12
C3
R11
TR17
TR13
TR15
TR16
TR20
TR21
TR23
TR22
TR24
TR19
TR14
TR33
TR35
TR34
R26
R2
R7
R9
R8
R3
D2
C1
R1
R5
R4
C2
D3
TR5
TR7
TR12
TR8
TR6
TR2
TR4
TR3
TR1
TR9
TR11
TR10
R6
R13
R15
R17
R19
R14
R18
TR18
R16