Icom IC-756PROIII Service Manual page 106

MAIN-A UNIT (2)
BUS LINE1
14V
8V
M5V
H5V
3R3V_d
HV
–5V
R8V
T8V
TRV ON : 0V
OFF : 4.8V
3R3V
Q622
UMH11N
4
5
6
MAIN-A (1)
RECI
MOSL
VOSL
RECO
REAF
DTAF
L3001
L3002
VRAC
VINT
MCK
M5V
VCS
MDAT
VDTI
VX1
R3025 C3013
10k 0.1
VX2
R3026
1.5M
7
IC3004B
NJM4558M
R3019
220
R3006
470
M5V
IC3002
BU4053BCFV
MICI 12
13
2
1
5
AMPO 3
6
MISL 11
MICE 10
9
MICO
VOGV
8V
–5V
M5V
14V
8V
M5V
H5V
3R3V_d
HV
–5V
R8V
T8V
RX 0V
TX 8V
7.8V
D611 D601
DA221 Q611 DA221
R622
2SD1619
1.5k
3
Q621
2SA1577
2
1
R612
R621 1k
47k
R613
10k
Q612 Q602
2SC4081 2SC4081
RX 4.4V
TX 0V
R3032
100k
10µH
100µH
IC3001
ISD4003-04MS
1 28
SS SCLK
2 27
MOSI VCCD
3 26
MISO XCLK
4 25
VSDD INT
5 24
NC RAC
6 23
NC VSSA
7 22
NC NC
8 21
NC NC
9 20
NC NC
10 19
W3001 NC NC
C3004 R3017
11 18
VSSA VCCA 1 2.2k
12 17
VSSA ANAIN+
13 16
AUDOUT ANAIN–
14 15
AMCAP NC C3003
0.1
R3028
6
–
82k
5
+
R3013 C3012
8 3
IC3004A 1 + 10k 0.047
2
NJM4558M –
4
C3030 C3025 R3021
0.1 10 220
16
14
IC3003
X0 X
R3020 M5282FP
15
X1 Y 47k
C3015
4 1 10
Y0 Z VCC2 VCC 10
2 9
Y1 IN+ VCAOUT
3 8
Z0 IN– CTL
4 7
Z1 OUT VCAIN
5 6
R3034
INH GND NC
1.2k
A
B
C
C3017
10
7 8
10 - 9
L3602 HF50ACC322513-B
L3601 HF50ACC322513-B
L3501 HF50ACC322513-B
UNLC
D3601
RX 8V
MA2S111
TX 0.2V
TMD
LFMD
Q601
LMFD
2SD1619
ISTA
IKEY
R602
1k
TRVI
RXS
R603
TXS
10k
TRAS
RX 0V
SENI
TX 4V
PWRS
CW KEY DOWN
SIDE TONE LIMIT :OFF
800mV
BEEP
0V
2.45mS
STON
IC321A
NJM4558M
SCPL
VOXL C3638
IC3005
AVXL
BU4053BCFV
16
12 14
X0 X
Explanatory notes
13 15
X1 Y
2 4
Y0 Z
VOLTAGE LINE
1
Y1
5
Z0
TX LINE
3 FORL
Z1
6 NSQO
INH
11 REFL
A
10
B
9 FMTL
C
7 8
C3032
0.1
C3021
0.1
R3650
4.7k
ALCL
R3030
SML
100k
PWRK
SKYS
RTKI
B
G
R
R3022
470
HSYNC
VSYNC
L3603 RCR-875D-472K
UNLC_
R3601
1k R3602
47k
Q3002
R3603 2.2k DTA114EE
R3604 1k LRXD_
R3605 1k LTXD_
R3608 1k
R3609 1k IKEY_
R3612 1k TRVI_
R3617 1k
R3618 1k
EP3622
EP3621
R3622 1k
R3625 1k BEEP_
C323
0.001
R323 R322 C322 R3626
8 2
–
1 120k 120k 0.0047 1k
3 STON_
+
4
R3637 1k SCPL_
0.1 R3638 1k VOXL_
R3639 1k AVXL_
R3641 1k ASO1_
R3640 1k ASO0_
R3642 1k ASO2_
ASL
IC3631
BU4053BCFV
1 16
Y1 VDD
2 15
Y0 Y
3 14
Z1 X
4 13
Z X1
5 12
Z0 X0
6 11
INH A
R3649
7 10
VEE B NTCG16
8 9
VSS C
D3508 D3509
RB706F-40 RB706F-40
R3647 1k PWRK_
R3643 1k SKYS_
R3644 1k RTKI_
R3572 39k FPDAT14
R3573 20k FPDAT8
R3574 10k FPDAT7
R3575 10k FPDAT6
R3576 10k
R3582 39k FPDAT11
R3583 20k FPDAT5
R3584 10k FPDAT4
R3585 10k FPDAT3
R3586 10k
R3592 39k FPDAT9
R3593 20k FPDAT2
R3594 10k FPDAT1
R3595 10k FPDAT0
R3596 10k
HSYNC
VSYNC
A
B
C
D
E
F
G
H
HV
I
RXF
J
K
L
FZVP
M
TMD_ FZRS
N
ISTA_
RXS_
TXS_
O
P
Q
R
S
T
U
V
W
X
Y
Z
AA