Yamaha GX-700, Service Manual

Page: 59 / 93

A B C D E F G H
1
2
3
4
5
6
I J K
7
8
GX-700/GX-700VCD
■
SCHEMATIC DIAGRAM (GX-700/GX-700VCD EFFECT)
* All voltage are measured with a 10M
Ω
/V DC electric 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.
POWER AMP
VIDEO SW & AMP
VIDEO AMP
DOLBY PROLOGIC DECODER
LEVEL CONTROL
0
0
0
23.5
-24.1
0 0
0 0
2.1
-0.8
-23.9
3.9
12.4 3.9 0 0.1 0.1 6.9
12.4
6.2
GX-700VCD ONLY
6.9
6.9 6.9
7.9
7.9
0
0
4.5
4.5
4.5 4.5
4.5
4.5
0
4.6
4.5
0.1
4.2
0
4.2
0
4.2 0
4.5
4.5
5.2
5.2
4.5
4.5
4.3
4.3
4.5
4.5
4.4
5.2
4.5
5.2
4.5
4.5
4.5 4.5
4.5
4.5
4.5
4.5
4.5
9.0
4.5 4.5 4.5 4.5
4.5
4.5 4.5 4.5
2.5
2.4
5.0
4.5
4.5
4.5
4.5
4.5
4.5
4.5
0
0.7
2.5
9.0
4.5
0
0
0
0
0 0
0
0
0
9.0
9.0
9.0
9.0
0
-8.5
0
12.3
0.1
0
0
0.1
-12.1
0
0
0
0
0
-12.0
0
0
0.9
12.2
0
0
0
0
0
0
0
0
0
0
4.9
-12.0
0
12.2
0
12.2
04
.6
-12.0
0
0
0
12.2 0
0.2
0
2.5
0
4.9
0
9.0
0
0
0
9.0
0.7 0
0
i
7
4
3
9
2
6
5
8
9
8
4
3
2
5
6
7
7
6
5
8
3
4
9 2
IC10 : LC7536-Y
Electric Controlled Volume
IC7 ~ 9 :
µ
PC4570HA
Dual OP-Amp
V
O1
2
–Vm
1
3
+Vm
1
4
V
EE
5
+Vm
2
6
–Vm
2
7
V
O2
8
V
CC
9
V
CC
1
1
– + – +
2
IC11 : LM1875T
Power Amp
+IN –IN
–VEE
OUTPUT
+
VCC
1 2 3 4 5
–
IC1 : LA7956
Video Amp
DRIVER
VIDEO
OUT
1
A
2
B
3
VIN1
4
GND
5
VIN2
6
VCC
7
VIN3
8
VIN4
9
CONTROL
4-INPUT 1-OUTPUT
VIDEO SWITCH
6 dB
AMP
16
VDD
LOGIC LEVEL
CONVER
TER
12 OX
7
VEE
6
INH
OUT C IN
13 IX OUT C IN
2
OY OUT C IN
1 IY OUT C IN
5 OZ OUT C IN
3 IZ OUT C IN
4 Z-COMMON
15
14 X-COMMON
Y-COMMON
9 C
10 B
11 A
8
VSS
INHIBIT
(Pin 6)
L
L
L
L
L
L
L
L
H
CONTROL INPUTS “ON” CHANNEL
0X (Pin 12), 0Y (Pin 2), 0Z (Pin 5)
1X (Pin 13), 1Y (Pin 1), 1Z (Pin 3)
0X, 0Y, 0Z
1X, 0Y, 0Z
0X, 1Y, 0Z
1X, 1Y, 0Z
0X, 0Y, 1Z
1X, 0Y, 1Z
0X, 1Y, 1Z
1X, 1Y, 1Z
NOTE
C
(Pin 9)
L
L
L
L
H
H
H
H
*
B
(Pin 10)
L
L
H
H
L
L
H
H
*
A
(Pin 11)
L
H
L
H
L
H
L
H
*
* Don’t Care
IC2 : HD14053BP
Triple 2 Channel Analog Multiplexers/Demultiplexers
IC5 : LV1035M
Dolby ProLogic Decoder
2 1 3 4 5 6 7 8 9 10 11 12 13 14 15 16
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
47 46 45 44 43 42 41 40 39 38 37 36 35 34 33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
L–BPF3
L–BPF2 L–BPF1 R–IN L–IN C–TRIM DC–CUT CMODE– CAP GND NS–BPF1 NS–BPF2 OSC1 CLK DATA ENABLE DATA CLK VSS
R–BPF2 R–BPF1
Sch
DC–CUT
Cch
DC–CUT
Rch
DC–CUT
Lch
DC–CUT
VREF
VCC
C–OUT S–OUT R–OUT L–OUT
AC–GND
L–IN
R–IN S–IN
DC–CUT
R RECT
DC–CUT
L RECT
VLR–TH
VLR–1
VLR–2
VCS–2
VCS–1
VCS–TH
L+R RECT
DC–CUT
L–R RECT
DC–CUT
R–BPF3
OSC
OSC
VDD
A/D
NS
D/A
DC–CUT
DC–CUT
L–MIX–OUT
R–MIX–OUT
S–OUT
ANALOG–GND
NR–IREF
NR–DET
VCC
DELAY–OUT
BPF
BPF
RECT
RECT
RECT
RECT
PB
LOGDIFF
LOGDIFF
DATA–DEC NOISE–GEN
VCR VCR
VCR VCR
VCR
PB
VCR
VCR VCR
VOL
VDD
VOL
R
L
R
L
C R L
R L
DEV
CTRIM
CTRIM 13PIN
20PIN
19PIN
OSC
NOISE–FIL
BFL–CONT
CH–CONT
VOL/MUTE
C–MODE
AOM
S
SMODE
STRIM
DC–CUT
SRAM
S
S
L
S
R
S
L
R
AOM-CONT
IN–FILTER
OUT–FILTER
B–NR
L5dB IN
CONTR
OL
S
1
12
CE 19
CLK 17
DI 18
LATCH
LEVEL SHIFT
SHIFT REGISTER
L CT1 3
L CT2 4
LVM 9
5
L5dB OUT
6
L1dB IN
8
L1dB OUT
R5dB IN 30
28
27
22
23
R1dB OUT
25
R1dB IN
26
R5dB OUT
R CT1
R CT2
R VM
13 VDD
21 VCC
14
VSS
10
VEE
2 7 11 15 16 20 24 29
NC
Point i (Pin32 of IC5)
V : 2V/div H : 0.1
µ
sec/div
DC range 1 : 1 probe
0V
72
SAME PAGE
I-8
P67
K-3
P73 H-8
P68 A-4
P69 A-4
P66 L-3
P67 K-3
P68 E-1
P69 E-1
SAME PAGE
A-2