Icom IC-756PROIII Service Manual page 99

A
B
C
D
R621
2.2k
S622 S621
DS621
(TRANSMIT) (POWER)
CL-200HR
(TIMER)
E
R622 R623 2.2k R624 4.7k R625 15k
6.8k
F
S623 S624 S625 S626
(TUNER) (MONITOR) (NB) (NR)
OFF 4.8V
TUNER ON 0V
MONITOR ON 1.2V
NB ON 2.4V
NR ON 3.7V
OFF 0V
ON 4.7V
Q622 Q623 Q624 Q625
DTC114EE DTC114EE DTC114EE DTC114EE
TNRD
G
H
I
MOND
J
NBD
NRD
R704 R706
(RF/SQL) (NR)
47k 47k
K
R701 R702
R703
RV-308 R705 RV-308
47k
47k
L
(AF) (BAL)
M
N
O
P
Q
R
S
T
R712 R716 R718 R720
R714
EVU-FLAE02B14 EVU-FLAE02B14 EVU-FLAE02B14 EVU-FLAE02B14 EVU-FLAE02B14
(MIC GAIN) (COMP) (BK-IN DELAY)
(RF POWER) (KEY SPEED)
-8V
U
V
W
X
3.0V
3.1V 1.7V
(BIAS CONTROL) (BRIGHT CONTROL) (GAMMA2)
Y
Z
C1404 0.1
C1405 0.1
AA 4.3V
C1406 0.1
SW
GAM1
AB
CPCN
COGC
(GAMMA 1) COMO
BASC
IC1521b
R1541
M5218AFP
R1544
10k
5 2.2k
AC + 7 CONT1
6
-
R1543 22k LCD CONTRAST
MAX 8.7V
MIN 0.9V
-15V
AD
-18V
AE
+14V
AF
AG
AH
AI
5VF
+14V NOTL R601 47k
PITL R602 47k
PB1A
PB1B
Q901
R904
DTC114EE PB2A
4.7k
MDM2 Q905 PB2B
2SB1201
Q902
R905
DTC114EE
6.8k
MDM1 Q904
2SC4081
PB(1/2)A,PB(1/2)B
D901
Q903
RD5.1M
R906
DTC114EE A
right
15k
MDM0
turn
B
R915
10k
A
left
turn
LDV B
DS901
R912
CL-200YG
330
DS904 METER BACKLIGHT
R914
CL-200YG MAX 11.9V
330
MIN 5.1V
METER BACK LIGHT
R917 R916
4.7k 2.2k
+
-
+ -
R709
10k
CP401
D701
DAN222
CP402
CP411
MEASUREMENT CONDITIONS
VOLTMETER :50kΩ/VDC CP412
OSCILLOSCOPE :20MHz 1MΩ 25pF
SUPPLY VOLTAGE:13.8V
DISPLAY : 14.1MHz USB
-7.5V DISPLAY BOARD
4.5V
+4R5V
R1526
C1401 C1409 C1521 0.1 100
0.1 0.1
IC1521a
8 M5218AFP
C1408
3
0.1 + 1
C1402
2
0.1 -
4
C1407
0.1
C1522 R1527 D1201
MA8030
0.1 100
C1403
0.1
Q1201
2SA1576
IC1401
M52338FP
1 32
MAIN IN R VCC1 C1110
2 31
CLAMP R EXT IN B 0.1
3 30
MAIN IN G SUB CONT B
4 29
CLAMP G EXT IN G
5 28
MAIN IN B SUB CONT R
6 27
CLAMP B EXT IN R
7 26 GAM2
SW GAM2
8 25 GAM1
HD IN GAM1
9 24 CONT1
CP CONT CONTRAST
10 23 BRGT
VCC2 BRIGHT
11 22
VEE FRP1 IN
12 21
FRP2 IN R OUT
13 20
COM GAIN SUB BIAS R Q1553
14 19
2SA1576
COM OUT G OUT
15 18
BIAS CONT SUB BIAS B
16 17
GND B OUT
C1553
10
COMO
Q1554
2SC4081
FRONT
J601 J1
W5
5VF 5VF
NOTL NOTL
R3 47k
PITL PITL
(PITCH)
PB1A PB1A
PB1B PB1B
R1
PB2A PB2A
RV-314
PB2B PB2B
R4 47k
GND
(NOTCH)
GND
GND
2
A
3
B (PBT2)
1
COM
5 S1
A
6
B (PBT1)
4
COM
4.8V
PBT BOARD
FRONT L1
J941 J1
W3 HF50ACC322513-B
J2
PHE
PHE
AFO
PHO R1 180
L2
PHE
PHE
HF50ACC322513-B
PHNI PHNI R2 180 PHONE
GND
GND
GND
GND
GND
GND
PHONE BOARD
PWRK
FRONT
J921 J1
EP1
W1 J2
DASH
DASH
DOT DOT
EP2
ELEC-KEY
GND
GND
GND
GND
GND
GND
GND
GND
KEY BOARD
J451
SPE
to
MAIN-A unit
Explanatory notes
J352
SSP
CHASSIS
VOLTAGE LINE
J452
P1
SSP SSP TX LINE
+
SP
SSPE SSPE RX LINE
-
R502
15k
-7R5V
HD
POLC
+14V
C1201 C1211 C1221
0.1 0.1 0.1
BL
GL
RL
D1211 D1221
MA8030 MA8030
Q1211 Q1221 IC542
2SA1576 2SA1576 TK16105M
1
2
3
4
R1551
100
Q1551
2SC4081
IC490
C1554
S-80942CNMC-G9C
10
1
OUT
2
VDD
3
VSS
R1552
100
Q1552
2SA1576
-15V
+18V
+14V
5VF
J301
LFMD
R301 1k LFMD
LMFD R312 1k LMFD
SRES R313 1k SRES
YOBI
R R315 47 R
G R316 47 G
B R317 47 B
HSYNC
R318 1k HSYNC
VSYNC R319 1k VSYNC
GND
GND
GND
from MAIN-A
GND unit J891
-8V
-8V
–8V
+18V +18V
14V
14V
+14V 14V
J321
14V
14V
14V
PHE
PHE
AFO
AFO
PHE
TMD
TMD
PWRK from MAIN-A
PWRK
unit J861
GND
GND
GND
GND
MICI
8V
MSND
MICE
SQSS SQSS
C323
0.0047
OFF 4.8V
Q321
DTC114EE UP 0.6V
DOWN 1.2V
FRONT
J322
W2
MICI
M8V
MUD MUD
SQLS
MSND
GND
MMICE
AFO
R501
1k
+18V
+14V
8
Q512
7 2SB1132
6
5
Q511
D512 C513
DTC114EE
RD5.1M 0.1
5 5
CO 1
4
2 W512
4
NC 12.1V
3
4
2
+ 1
3
IC492 R511 -
IC511a
TC4S81F 10k
11
NJM2092V
+14V
10 - 2
MIC BOARD
C1
0.0047
J1
7 1
6 8 2
5 3
4
J2
MICI
L1 100µH
M8V
MUD L3 100µH
SQLS
L4 100µH
MSND
GND
MMICE
AFO
L6
HF50ACC322513-B
C505 0.0047
C506 0.0047
J531
Q514
2SB1132
L5V
HD
VD VD
POLC POLC
IC511d
NJM2902V
Q515 GND
W504
DTC114EE
12
+ 14
13 L5V
-
RL
to
GL
Q513 LCD
BL
DTC114EE unit
VCOM
GND
IC511c
W502
IC511b NJM2902V L/R
12.1V
NJM2092V
10 U/D
+ 8
5 9
+ 7 - W506
6
-
N/P
L18V
-15V
CP5