Service manual
ABCDEFGH
1
2
3
4
5
6
IJK
7
8
DVR-S120/NX-P120
79
■ DVR-S120 SCHEMATIC DIAGRAM (SUB)
3.9
0
0
0
0
0
0
0
0
0
0
0
0
0
4.9
4.9
4.9
4.9
4.9
3.9 4.9
4.9
3.6
3.6
5.0
1.3
0
0
12.0
20.7
3.6
4.9
12.0
20.7
20.7
20.9
13.5
11.8
5.0
5.0
-12.2
-12.2
-12.0
-21.7
-21.2
5.0
4.8
6.7
6.2
5.0
5.7
7.0
12.5
12.5
11.8
4.8
12.5
10.8
3.7
5.7
20.9
-0.1
-21.0
5.5
12.8
5.0
1.3
0
0
5.0
5.0
12.8
4.9
5.0
0
3.7
3.6
12.7
7.9
3.6
6.3
6.3
0.7
7.9
6.2
0
0
0
0
0
0
0
0
0
0
0
-21.0
-14.2
-5.1
0
0
0
0
0
0
11.8
0
0
-0.1
-0.1
AC7.9
AC4.9
AC10.4
AC32.6
3
3
CH1
CH2
4
1
812
7
13
12
14
3
2
7
6
8
1
2
34
6
5
9
10
5
PHONES
(1)
(1)
L275-278
C362
C361
BLM21P600SG
Page 77
A5
to MAIN (1)
Page 76
J7
to MAIN (2)
Page 78
D1
to MAIN (3)
Page 77
E1
to MAIN (1)
Page 76
J5
to MAIN (2)
Page 78
I3
to MAIN (3)
Page 74
B1
to DVD M5
Page 77 J4
to MAIN (1)
X : NOT USED
* All voltages are measured with a 10M
Ω
/V DC electronic volt meter.
* Components having special characteristics are marked
Z
and
must be replaced with parts having specifications equal to those
originally installed.
* Schematic diagram is subject to change without notice.
Point e
CH 1 : Emitter of Q272
CH 2 : Colector of Q271
CH 2
CH 1
↑
AC POWER ON
(Connect the power cable)
↑
AC POWER OFF
(Disconnect the power cable)
IC275 : PQ1CG21H2F
IC276 : PQ1CG2032FZ
Voltage Regulator
V IN
COM
ON/OFF
O ADJ
V OUT
OVER CURRENT
PROTECTION
CIRCUIT
OVER HEAT
PROTECTION
CIRCUIT
SOFT
START
PWM
COMP.
VOLTAGE
REGULATOR
ON/OFF
CIRCUIT
ERROR
AMP.
S
R
F/F
OSCILLATOR
VREF
1
3
4
5
2
Q
IC311 : NJM2904M
Dual OP-Amp
–+
OUT
1
–IN
1
–V
CC
+V
CC
OUT
2
1
2
3
4
5
+IN
1
–IN
2
+IN
2
– +
6
7
8
IC312 : TC74HCT00AF
Quad 2 Input NAND
A1
B1
A2
V
DD
B4
1
2
3
4
11
Y1 A4
Y4
12
13
14
B2
Y2
B3
A3
5
6
7
V
SS
Y38
9
10