Icom IC-7400 Service Manual page 74

• MAIN UNIT (1/3)
C111
EP101 EP102
-8V
22
14V
21
GND
20
8V
19
GND
18
T8V
17
GND
16
R8V
15
GND
14
5V
13
GND
12
ALC
11
AGC
10
TNV2 TNV2
9
TNV1 TNV1
8
RTXS R100 TXS
7
RSKY R103 SKYS
6
DRIV DRIV
5
RDRS R101 DRES
4
RBST R104 BSTB
3
RMDT R102 MDAT
2
RMCK R105 MCK
1
J100
14V
8V
5V
H5V
HV
-8V
-5V
8V
5V
-5V
-8V
ISTA HV
ISTA HV 14VA
IKEY
IKEY
FMTL
FMTL
PWRK VOXL MIC
PWRK VOXL MIC
AVXL MICE
MICE
AVXL
LFMD MIGV
MIGV
LFMD
LMFD FORL ACCMOD
LMFD FORL ACCMOD
REFL
REFL
PWRS ALCL TIF
PWRS ALCL TIF
THML_ RIF
THML_ RIF
ANTS VCCL
ANTS VCCL
DPTL AGC
DPTL AGC
UNSB
UNSB
NBS STON MSL1
MSL1
NBS STON
9K6S BEEP MSL2
MSL2
9K6S BEEP
MODS MONV
MONV
MODS
FMS SPCH SPCH
SPCH
FMS SPCH
AMS CIV FMTL
FMTL
AMS CIV
PHFS CIVE MODS
MODS
PHFS CIVE
P50S
P50S
P2MS DCK AAFO
P2MS DCK AAFO
2F3K DDTW AFG1V
2F3K DDTW AFG1V
2F15 DDTR AFG2V
2F15 DDTR AFG2V
MSL1 DRQW AFMS
MSL1 DRQW AFMS
MSL2 DRQR PAFO
MSL2 DRQR PAFO
DSTR PAFE
DSTR PAFE
OVDK DWBY
OVDK DWBY
SKYS DCBY DOUT
SKYS DCBY DOUT
RTKI DRBY
RTKI DRBY
SENI SQLS
SENI SQLS
TRAS DSKY
TRAS DSKY
RXS DSST BEEP
RXS DSST BEEP
TXS CTFL STON
TXS CTFL STON
RTDT
RTDT
SQLS TOFF VOXL
SQLS TOFF VOXL
AFMS VSQL AVXL
AFMS VSQL AVXL
SQL NSQL
SQL NSQL
DATA
DATA
START PCK OVDK
START PCK OVDK
KEY PDAT 9K6S
KEY PDAT 9K6S
CON2
CON2
PST1 AMS
PST1 AMS
PST2
PST2
PST3
PST3
PST5
PST5
UNLC DRQW DWBY
UNLC DRQW DWBY
DCK DDTW
DCK DDTW
BSTB
BSTB
FSTB DRQR DDTR
FSTB DRQR DDTR
ASTB DRBY DSTR
ASTB DRBY DSTR
DRES CTFL NSQL
DRES CTFL NSQL
TOFF RTDT
TOFF RTDT
MCK VSQL DCBY
MCK VSQL DCBY
MDAT
MDAT
5V
DSKY DSST
H5V DSKY DSST
DRES
DRES
L122
PHV
30
P14V
29
P14V
28
P14V
27
P14V
26
P14V
25
P14V
24
P14V L120
23
P14A
22
P14A L121
21
PICH L123
20
PICL
19
PGND W120 L124
18
GND
17
FVFR L125
16
PVRF
15
GND L126
14
PT8V L127
13
GND
12
P8V L128
11
P8V
EP120
10
THML
9
PH5V L129
8
P5V L130
7
P5V
6
PMCK R120
5
PMDT R121
4
PFSB R122
3
PDRS R123
2
PPWS R124
1
J120
22
C14V
21
L140
C14V
20
GND
19
L141
CTBV
18
C14V
17
GND
16
C5V
15
L142
C5V
14
GND
13
L143
C-8V
12
GND
11
GND
10
L144
CFDR
9
L145
CREF
8
GND
7
R140
CDR5
6
GND
5
R141
CANT
4
GND
3
R142
CIST
2
R143
CIKY
1
J140
Q201
Q200
L201
L200
8V
R8V
2IF
J250
D252
D250
L251
C250
D251
D253
L252
AGC AGC
14V 14V
T8V T8V
R8V R8V
8V 8V
5V 5V
14VA 14VA
-8V -8V
Q330
L330
ALC
R370
R363 IC360
6
7 D362
5
R366
C302
R364
W361
R302
IC360
2
D363
1
R300
IC300
ALC 2 3
R367
IC300 1
R365
3
R361
C360
4 8
C300
V+ D360 V+ IC360
V- V-
11 4
C301
C364
C361
14V
T8V
R8V
8V
5V
14VA
-8V
Q305
D310 D311
D312
R319
HD304
VCCL
CP301
R327
CP300
R313 R316
6
R318
7
5
IC300
R310 R314
Q300 Q301 Q302 Q304
ICH
ICL
VFOR
VREF
CON2
R801 R804 C803
14V
R802
THML_
MCK J802 Q801
MDAT MF+ Q802
1 CP160
FSTB GND
2 CP161
DRES
CP162
PWRS
D801 CP163
CP164
CP165
CP166
CP167
CP168
CP169
CP170
CP803 -5V
CP171
CP172
CP173
CP174
L181
J160
FOR
REF
DRES
To PLL UNIT
ANTS
ISTA
IKEY
Q202
R211
Q203
L202
L203
Q204
C264
L253
R258
FI271
C259
1 2
R257
Q250
L254
R263
C265
14V
T8V
R8V
8V
5V
14VA
-8V
R414
R415
C409
R337 C334
R407
D380
D382
W400
C400
D381
R336 D383
R383
FI381
12
R388
R390
W380
4 3
5 2
6 1
Q381
14V
T8V
R8V
8V
5V
14VA
-8V
ALC
D552
R559
9
R561 8
R551 R556
10
IC300
Q309
Q307
C304 R560
IC300
13 D553
D305
14
12
C305 R555
Q306
R511
EP182
VCC
11
AO11
12
CP180 AO12
13
EP181 CP181 R504 DO
14
CP182 LD
R505 15
CP183 CLK
R506 16
CP184 DI
17
CP185 AO1
18
CP186 AO2
19
CP187 GND
20
CP188
CP189
CP190
CP191
CP192
CP193
CP194
CP195
CP196
J180
To FRONT UNIT
Q206
R217 6
Q208
7
5
4
R221 3
IC200
Q205 2 5
1 6
W270
IC280
1 8
FI272 2 7
3 6
4 5
1 2
14V
T8V
R8V
8V
5V
14VA
-8V
3LO_
IC400
1 14
+SI VEE
2 13
GAIN NC J400
3 12
GAIN -OUT
4 11
-SI NC R413 2
5 10
BIAS -CI 1
6 9
+OUT NC
C406
7 8
NC +CI
3LO
R409
Q700 D700
R701
14V
T8V
R8V
8V
5V
14VA
-8V
Q452
D450
C500
4
V+
IC200
GND
11
Q453
C501 D451
R502
2
R503
1
R500
3
IC200
Q511
8V
D720 8V 14V
5V
R780 R783
D781
Q780 R781
R782
VDD
10
AO10
9
AO9 R724 R726
8
AO8
7 144M
R720 D722
AO7 Q721
6
AO6
5
AO5
4
AO4
3
AO3
2
R721
VSS
1 5V 5V
IC502
R725 R727
R527 HF&50M R722 D723
Q722
R528
Q720
R723
R523
9
8 HF&50M SEND
R521
10 144M SEND
IC200
Q790
R526
Q788
Q786 Q785
13 Q787
14
R524
12
IC200
NOTICE: Refer to the PARTS LIST for the value and name of each component.
12 - 4
L280
L281
R281
IC281 IC282
5 1 5 1
2 2
4 3 4 3
C282 C283
14V
CP9005
T8V
CP9006
R8V
CP9007
8V
CP9008
5V
CP9009
14VA
CP9010
-8V
L700
J700
6 5
L701
4 3
2 1
L702
L703
L704
RL740
J740
L741
L742
L740 J741
SSP
1
PAFE
2
Q740
14V
CP9011
T8V
CP9012
R8V
CP9013
8V
CP9014
5V
CP9015
14VA
CP9016
-8V
CP9017
R450
R451
L760
EKY J761
1
L761
R452 EST
2
L762 E14V
3
L763 EGND
Q450 4
R453
EP761
J760
R454
EP760
R455
Q451
MP791
R790
RL781
L795 J782
L796
C794
EP780
Q784
CP788
EP781
J780
L793
L780 6
7
L781 1 7 6
EP782
L782 3
3 1
L783 EP783 4
L794 2
5
5 4
8V
2
J781
L784
6
L785 L789 7
7 6
1
L787 8
3
3 8 1
L788 4
2
5
5 4
L790 2
EP784
L791
EP786
EP788
EP790
L786
R811
D810
Q810
R812
R813