![background image](http://html.mh-extra.com/html/icom/ic-7400/ic-7400_service-manual_612265086.webp)
12 - 3
C1021
0.001
(2)
UNIT
MAIN
CP9008
CP9007
2
ALC
MA2S728
D364
CP9012
CP9013
CP9015
CP9017
R512 1k
56k
R1062
680k
R1063
MA2S111
D553
MA2S111
D552
0.0047
C1245
RIF
12
13
-
+
14
NJM2058M
IC1300
R1309 100k
CP9001
14VA
T8V
RIF
AGC
R1470 100k
470k
R1007
100p
C1006
680k
R1000
0.1
C1002
680k
R1001
10
C1004
SQLS
47k
R1126
C1406 1
470
R803
CP803
CP801
CP802
GND
GND
GND
GND
DRQW
DWBY
DCK
DDTW
GND
GND
DRQR
DDTR
DRBY
DSTR
GND
GND
CTFL
NSQL
TOFF
RTDT
VSQL
DCBY
GND
GND
DSKY
DSST
DRES
GND
GND
MF+
GND
MF1
to CHASSIS
unit J1601
from RF
from/to
RF unit
J261
3LO
100
µ
L181
W180
MAIN UNIT (1)
NJM2058M
IC300
2.2M
R559
8
10
9
-
+
3.3k
R557
100k
R554
68k
R551
R561
NTCCM20123SH
R562
NTCCM20123SH
100k
R556
VREF
REF
DAN222
D551
DAN222
D550
ICL
ICH
NJM2058M
IC300
1M
R560
14
12
13
+
-
RV-150
R555
33k
R558
33k
R553
47k
R552
47k
R550
MONV
0.001
C803
22
R804
22
R801
10k
R802
2SB1201
Q801
FCNT
2SC4116
Q802
MA8068
D801
0.001
C802
100
C801
J802
W362
NJM2058M
8V
IC200
NBV
NBV
3LO
100
R385
10k
R384
3.3M
R300
120p
C1310
0.47
-5V
C1304
2SD1801
Q1260
LA4425A
IC1240
27k
R1086
100
R1085
0.47
C1081
3.3k
R1020
NJM2904M
IC1001
100
R1160
CP1001
CP1104
CP114
CP9016
CP9010
CP9006
CP9005
CP9004
CP9003
CP9000
P2MS
3LO
3LO
CP400
CP401
J400
BUS LINE2
BUS LINE1
5V
14V
8V
H5V
DTC114EU
Q720
P2MS
DAN222
D720
4.7k
R724
4.7k
R780
4.7k
R725
HF & 50M SEND
MA2S111
D723
4.7k
R727
33k
R722
15k
R723
2SC4081
Q722
SEND
144M SEND
MA2S111
D722
4.7k
R726
33k
R720
15k
R721
2SC4081
Q721
DAN222
D721
SEND
MA2S111
D781
4.7k
R783
33k
R781
15k
R782
2SC4081
Q780
SENI
TXS
RXS
1k
R454
4.7
R453
4.7k
R455
2SD1619
Q453
2SC4081
Q451
0.47
C451
DA221
D451
2SD1619
Q452
2SC4081
Q450
10k
R452
1k
R451
4.7
R450
0.47
C450
DA221
D450
R8V
T8V
DRIV
1k
R527
TNV1
R526 100k
100k
R525
NJM2058M
IC200
12
13
+
-
14
47k
R524
1k
R528
TNV2
R523 100k
100k
R522
8
NJM2058M
IC200
10
9
+
-
47k
R521
2SC4081
Q511
1k
R511
MONV
POCV
MIGV
BAND
470
R503
100k
R502
100k
R501
1
-
+
2
3
BANV
TIF
47k
R500
BANV
0.01
C503
10
C502
270
R508
150
R507
R506 1k
R505 1k
R504 1k
MDAT
MCK
ASTB
AFG2V
AFG1V
VDD
AO10
AO9
AO8
AO7
AO6
AO5
AO4
AO3
VSS
GND
AO2
AO1
DI
CLK
LD
DO
AO12
AO11
VCC
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
M62352GP
IC502
EALC
NJM2058M
IC200
0.1
C500
GND
V+
0.1
C501
4
11
100k
R323
10k
R322
2SA1576
Q307
10
C305
DTC114EU
Q306
AMS
DTC114EU
Q304
RV-156
R320
P2MS
DTC114EU
Q302
RV-156
R317
P50S
DTC114EU
Q301
RV-156
R311
PHFS
DTC114EU
Q300
RV-156
R306
UNSB 2SA1576
Q303
22k
R319
DTC144TE
Q305
470k
R321
2SA1576
FMS
Q308
22k
R327
DTC144TE
Q309
R328
10k
W300
1
C307
MA2S111
D305
0.001
C304
330
R318
1.5M
R316
NJM2058M
IC300
5
6
+
-
7
22k
R310
220k
R314
100k
R313
CP301
CP300
1SS385
D303
100k
R308
5V
POCV
10k
R307
DAN222
D312
1k
R326
MA8039
D311
MA8039
D310
14V
VEE
NC
-OUT
NC
-CI
NC
+CI
NC
+OUT
BIAS
-SI
GAIN
GAIN
+SI
NJM1496V
IC400
100
R413
0.0047
C406
100
µ
L402
10
C408
0.1
C407
3.3k
R412
0.1
C405
1k
R410
680
R411
0.1
C404
10
C403
3.9k
R409
10
C402
0.1
C401
100
µ
L400
3.3k
R408
5.6k
R406
1k
R405
R407 220
1k
R404
0.1
C409
4.7k
R414
1k
R415
TIF
8V
8V
8V
R8V
T8V
14V
5V
8V
14V
8V
ALC
-
8V
-
8V
W400
0.0047
C400
8
9
10
11
12
13
14
7
6
5
4
3
2
1
10k
R400
MA77
D383
MA77
D382
NJM4558
IC360
0.1
C360
V-
V+
0.1
C361
8
4
0.1
C301
NJM2058M
IC300
0.1
C300
11
4
V+
V-
-8V
33k
R369
10
C363
REFL
-
8V
-
8V
8V
8V
8V
220
R366
NJM4558M
IC360
NJM4558M
IC360
MA2S111
D362
R370
330k
R363
100k
5
6
+
10k
R364
7
100k
R360
FORL
33k
R368
10
C362
220
R367
MA2S111
D363
W361
3
2
-
-
+
1
10k
R365
100k
R361
MA2S728
D361
VFOR
FOR
1SS385
D360
REF
VREF
4.7k
R324
ALCL
8.2M
R302
0.0047
C302
NJM2058M
IC300
2.2M
R301
3
2
-
+
1
8V
TIF
ALC
R8V
T8V
5V
14V
-8V
8V
TIF
W380
2F15
XP4311
Q381
1
2
4
5
3
6
XP4311
Q208
100
R390
3.9k
R389
220
R388
0.1
C383
0.1
C382
10k
R387
2.2k
R386
1
2
CFWM455D
FI381
220
R383
0.1
C381
0.1
C380
10k
R382
3.9k
R381
MA77
D381
MA77
D380
4.7k
R380
0.0047
C334
NTCCM20123NH
R337
100k
R336
22k
R334
0.0047
C333
10k
R335
ALC
T8V
2SK882
Q330
W331
10k
R333
RV-150
R331
100
R332
0.1
C332
LS-469
L330
0.47
C331
0.1
C330
1k
R330
NBS
3
2
6
5
1
4
22k
R223
10k
R222
100
µ
L281
10
C285
10
C284
100
µ
L280
-8V
5V
14V
8V
H5V
0.001
C286
10k
R282
1M
R281
0.1
C283
0.1
C282
TC4SU69F
IC282
5
4
3
2
1
TC4SU69F
IC281
4
5
3
2
1
0.1
C281
1.5k
R280
RIF
0.1
C280
8
7
6
4
3
5
8V
RIF
1
TC4W53F
IC280
W270
1
2
CFWM455D
FI272
CFWM455D
FI271
2
1
0.0047
C264
LS-468
L254
0.1
C263
10
R261
10k
R264
0.1
C265
1.5k
R263
10k
R256
1.5k
R260
68
R259
0.1
C261
3SK131
Q250
47
R258
1.5k
R257
0.001
C260
0.0047
C259
LS-468
L253
1SV308
D253
1SV308
D252
8V
R8V
470
R255
1k
R254
100
C257
0.1
C256
270
R253
0.1
C255
LS-468
L252
100k
R252
0.0047
C253
0.0047
C251
1k
R251
LS-468
L251
1SV308
D251
1SV308
D250
2IF
1m
L200
330
µ
L250
470
R250
0.1
C250
CP250
J250
47
R221
NJM2058M
IC200
5
6
-
7
+
UN911H
Q207
220
C218
0.22
C217
6.8k
R220
UNLC
MA2S111
D202
2SC4081
Q206
47
C216
6.8k
R219
0.1
C215
47
C214
2SA1576
Q205
R217 2.2M
330
R218
47k
R215
47k
R216
2SC4081
Q204
CP201
CP200
470p
C212
100k
R213
1SS375
D200
0.0022
C211
0.1
C210
1k
R212
22k
R211
2SC4081
Q203
22k
R210
0.0047
C209
LS-450
L203
0.1
C208
100
R209
4.7k
R208
W1240
W200
2SK882
Q202
22k
R207
100
R206
0.1
C204
LS-450
L202
470
R205
0.1
C203
2SK882
Q201
22k
R204
100
R203
-8V
5V
14V
8V
R8V
H5V
0.1
C201
LS-450
L201
470
R202
0.1
C200
2SK882
Q200
RV-152
R200
NJM4558M
IC1060
3
2
-
1
+
NJM4558M
IC1060
10
C1060
5
6
-
+
7
10
C1065
470k
R1061
MONI
1k
R1040
MSL2
0.1
C1041
MSL1
0.1
C1040
8
7
6
4
3
5
1
2
TC4W53F
IC1040
AGC
NJM2058M
IC1401
100k
R1023
12
13
-
+
14
0.1
C1020
22k
R1021
DAGC
100k
R1022
5
6
-
+
7
100
R1065
10
C1061
0.1
C1064
NJM4558M
IC1060
-8V
0.1
C1063
4
8
V+
V-
10
C1062
100
R1064
100
R1109
100
R1110
10
C1107
0.1
C1108
0.1
C1109
10
C1110
µ
PC4574G2
IC1120
11
4
V+
V-
-8V
µ
PC4574G2
IC1120
12
13
-
+
14
TIF
µ
PC4574G2
IC1120
3
2
-
+
1
0.0027
C1104
270p
C1106
1k
R1107
1k
R1106
µ
PC4574G2
IC1120
5
6
-
+
7
390p
C1103
1k
R1105
0.0015
C1102
1k
R1104
0.0012
C1100
1k
R1103
µ
PC4574G2
IC1120
27k
R1102
8.2k
R1101
10k
R1100
220k
R1108
DTIF
8V
5V
-5V
82k
R1002
0.039
C1001
82k
R1003
82k
R1004
0.0015
C1003
NJM2904M
IC1001
3
2
-
+
1
NJM2904M
IC1001
1M
R1009
120k
R1005
0.1
C1005
0.0047
C1007
2.2M
R1008
82k
R1006
8
+
-
9
10
FMTL
470
R1012
0.1
C1008
100
R1013
4
8
V+
GND
AMS
DTC114EU
Q1261
10k
R1141
2SK1829
Q1140
0.047
C1141
2.2k
R1088
8.2k
R1087
10
C1087
10
C1086
10
C1080
100k
R1080
47k
R1081
SPCH
0.1
C1082
100k
R1083
10
C1085
47k
R1084
470p
C1083
100k
R1082
10
C1084
10
9
8
7
6
5
4
3
2
1
VCAOUT
M5282FP
IC1080
+IN
-IN
OUT
GND
VCC
VC
VCAIN
NC
VCC2
8V
5V
470
C1261
100
C1260
47
R1260
470
C1243
PAFE
AGC
14V
-
8V
T8V
5V
R8V
8V
ALC
PAFO
470
R1242
0.1
C1244
470
C1242
CP1244
CP1245
CP1243
CP1242
4
2
1
3
5
CP1241
0.0022
C1241
10
C1240
1k
R1241
10k
R1240
100
R1222
10
C1221
W1220
AFMS
100
R1221
10
C1220
8
7
6
5
4
3
2
1
TC4W53F
IC1220
100k
R1220
1
R1192
100k
R1193
22k
R1192
270k
R1190
100
R1189
AFG2V
5V
8V
AFG1V
82k
R1191
1
C1191
470
C1190
1
C1189
10
C1187
47k
R1185
AAFO
10
C1188
47k
R1188
4.7k
R1187
10
C1186
0.0022
C1185
10k
R1186
VCAOUT
M5282FP
IC1180
+IN
-IN
OUT
GND
VCC
VC
VCAIN
NC
5
3
VCC2
6
2
7
8
9
4
1
10
1k
R1184
2.2
C1184
10
C804
1k
R1162
0.47
C1182
1k
R1183
0.47
C1183
1k
R1182
0.47
C1181
2.2k
R1181
15k
R1180
0.47
C1180
10
C1160
470
C193
100
R1161
10
C1161
1
C1140
2.2k
R1140
DOUT
4
3
2
1
8
7
6
5
TC4W53F
IC1160
W1120
RV-145
R1469
CP1461
14V
-
8V
-
5V
5V
8V
CP1460
2.2k
R1468
DRIF
BA15532F
IC1460
+
-
7
6
5
16084BH
NTCCM-
R1466
2.2k
R1467
BA15532F
IC1460
+
-
C1464 0.0068
680p
C1465
1.5k
R1465
1
3
330p
C1466
100p
C1467
2
1.5k
R1464
270p
C1463
0.0027
C1462
1.5k
R1462
100k
R1461
0.1
C1470
10
C1461
10
R1463
0.1
C1469
BA15532F
IC1460
10
C1460
0.1
C1468
4
8
V+
V-
10
R1460
100
R1423
0.0047
C1426
10
C1423
NJM2058M
IC1401
0.0047
C1422
10
C1421
11
4
V+
V-
100
8V
-
8V
8V
R1420
-5V
H5V
R8V
8V
14V
5V
T8V
-8V
14VA
NJM2058M
IC1300
8
+
-
9
10
100k
R1313
220p
C1309
100k
R1312
220k
R1314
0.1
C1308
OVDK
8V
NJM2058M
IC1300
7
+
-
6
5
150k
R1310
100k
R1311
0.1
C1307
100k
R1308
8V
8V
5V
0.1
C1306
1SS385
D1300
NJM2058M
IC1300
680k
R1307
1
+
-
3
2
0.1
C1305
100k
R1306
100k
R1305
15k
R1302
18k
R1303
100k
R1304
10k
R1419
0.47
C1420
NJM2058M
IC1401
+
-
0.0047
C1416
0.0012
C1417
22k
R1418
8
10
560p
C1418
10p
C1419
9
22k
R1417
NJM2058M
IC1401
+
-
7
5
6
82p
C1415
680p
C1414
22k
R1416
470p
C1412
0.0027
C1413
22k
R1415
DTAF
9K6S
MODS
0.1
C1301
NJM2058M
IC1300
100
R1300
10
C1302
100
R1301
10
C1303
11
4
V+
GND
0.1
C1300
10k
R1315
DATA
2.2
C1409
10k
R1409
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
VDD
Y
X
X1
X0
A
B
C
VSS
VEE
INH
Z0
Z
Z1
Y0
Y1
BU4053BCFV
IC1310
100
R1480
10
C1481
100
R1481
NJM4558M
BEEP
4
8
10
C1480
V-
V+
-5V
5V
8V
PAFO
-
5V
-
5V
5V
-
5V
5V
8V
-
5V
5V
22k
R1288
10k
R1287
220k
R1284
100k
R1286
0.1
C1285
R1282 220k
C1282 100p
NJM4558M
IC1280
AVXL
6.8k
R1281
10
C1281
+
-
7
6
5
NJM4558M
IC1280
100k
R1289
0.1
C1286
0.033
C1284
5.6k
R1285
C1283 0.001
R1283 150k
3
2
1
+
-
0.1
C1280
3.9k
R1280
VOXL
270p
C1411
0.0022
C1410
22k
R1414
1k
R1413
6.8k
R1412
NJM2058M
IC1401
1
3
2
10k
R1410
220k
R1411
+
-
ACCMOD
10k
R1408
2.2
C1408
10k
R1407
2.2
C1407
MIGV
47k
R1406
W1401
100k
R1404
C1405 10
10
8V
R1403
220
R1425
0.1
C1429
100
C1428
-5V
H5V
R8V
8V
14V
5V
T8V
-8V
14VA
unit J901
to DSP
unit J902
to DSP
TOFF
CP1019
RTDT
CP1020
VSQL
CP1021
DCBY
CP1022
DSKY
CP1027
DSST
CP1028
DRES
CP1029
NSQL
CP1018
CTFL
CP1017
DSTR
CP1014
DRBY
CP1013
DDTR
CP1012
DRQR
CP1011
DDTW
CP1008
DCK
CP1007
DWBY
CP1006
DRQW
CP1005
CP1030
J1000
DTIF
CP1121
DRAF
CP1118
MONI
CP1114
DAGC
CP1113
CP1110
CP1109
DTAF
CP1105
DRIF
2IF
CP1102
CP1101
J1001
GND
DRIF
GND
GND
DTAF
GND
GND
GND
8V
8V
GND
GND
DAGC
MONI
GND
GND
GND
DRAF
GND
GND
DTIF
GND
-5V
C192 0.0047
C191 0.0047
C190 0.0047
C189 0.0047
C188 0.0047
C185 0.0047
C184 0.0047
C183 0.0047
C180 0.0047
MIC
MICE
SEND
SQL
PWRK R180 1k
R181 1k
DRES
R182 220
R183 220
LMFD
LFMD
PAFE
PAFO
SPS
R184 1k
CP180
CP181
CP182
CP183
CP185
CP184
CP186
CP187
CP194
CP188
CP189
CP190
CP191
CP192
CP193
CP195
CP196
C163 0.0047
C162 0.0047
14V
GND
8V
GND
5VL
5VL
GND
GND
-8V
GND
MIC
MICE
SEND
SQL
FPWK
FDRS
GND
FLMF
FLFM
PAFE
PAFO
FSPS
J180
board J601
to S-LOGIC
CON2
PCK
PDAT
PST5
PST4
PST3
PST2
PST1
UNLC
DRES R160 1k
C164 0.0047
C160 1000
C161 0.0047
CP160
CP161
CP162
CP163
CP164
CP165
CP166
CP167
CP168
CP169
CP170
CP171
CP172
CP173
CP174
FCNT
CON2
PCK
PDAT
PST5
PST4
PST3
PST2
PST1
LDRS
GND
UNLC
GND
GND
5V
5V
GND
8V
8V
GND
14V
14V
FCNT
unit J1001
to RF
J160
IKEY
ISTA
ANTS
DRES
REF
FOR
R143 1k
R142 1k
R141 1k
R140 1k
L145 10
µ
L144 10
µ
L143 HF50ACC322513-B
L142 HF50ACC322513-B
L141 HF50ACC322513-B
L140 HF50ACC322513-B
R124 1k
R123 1k
R122 100
R121 100
R120 100
CP151
C149 0.0047
CP150
C148 0.0047
CP149
C147 0.0047
CP148
C146 0.0047
CP147
C145 220p
CP146
C144 220p
CP145
C143 0.0047
CP144
C142 0.0047
CP143
C141 0.0047
CP142
C140 0.0047
CP141
CP140
CIKY
CIST
GND
CANT
GND
CDRS
GND
CREF
CFOR
GND
GND
C-8V
GND
C5V
C5V
GND
CT8V
GND
C14V
C14V
C14V
unit J7
to CTRL
J140
HV
-
8V
14V
8V
T8V
5V
14VA
H5V
-
5V
PWRS
DRES
FSTB
MDAT
MCK
L130 HF50ACC322513-B
H5V
L129 HF50ACC322513-B
THML
L128 HF50ACC322513-B
L127 HF50ACC322513-B
VREF
L126 10
µ
VFOR
L125 10
µ
ICL
ICH
L124 10
µ
L123 10
µ
L121 EXC-ELDR25C
L120 EXC ELDR25C
L122 10
µ
unit J5
to PA
W120
CP137
CP138
CP139
C135 0.0047
C136 0.0047
CP136
C134 0.0047
CP135
C133 100p
CP134
C132 100p
CP133
C131 100p
CP132
CP131
C129 0.0047
CP130
CP129
CP128
C126 0.0047
CP127
C125 0.0047
CP126
CP125
C124 0.0047
CP124
CP123
C123 0.0047
CP122
C122 0.0047
CP121
CP120
C120 0.0047
PPWS
PDRS
PFSB
PMDT
PMCK
P5V
P5V
PH5V
THML
P8V
P8V
GND
PT8V
GND
PVRF
FVFR
GND
PGND
PICL
PICH
P14A
P14A
P14V
P14V
P14V
P14V
P14V
P14V
P14V
PHV
J120
unit J2
to RF
MCK
MDAT
BSTB
DRES
DRIV
SKYS
TXS
TNV1
TNV2
AGC
ALC
R105 100
R102 100
R104 100
R101 1k
R103 1k
R100 1k
14VA
5V
R8V
T8V
8V
14V
-8V
CP115
CP116
CP107
CP106
C110 100p
C111
0.001
CP113
C109 100p
CP112
C108 100p
CP111
C107 0.0047
CP110
C106 0.0047
CP109
C105 0.0047
CP108
C104 0.0047
CP105
C103 0.0047
CP104
CP103
C102 0.0047
C101 0.0047
CP102
C100 0.0047
CP101
CP100
CP117
RMCK
RMDT
RBST
RDRS
DRIV
RSKY
RTXS
TNV1
TNV2
AGC
ALC
GND
5V
GND
R8V
GND
T8V
GND
8V
GND
14V
-8V
J100
680
R1424
MICE
MIC
10
µ
L1401
4.7
C1400
0.0047
C1427
47k
R1402
2.2
C1401
4.7k
R1400
100k
R1401
470p
C1402
C1403 10
2.2
C1404
10
9
8
7
6
5
4
3
2
1
NC
VCAIN
VC
VCAOUT
VCC
GND
OUT
-IN
+IN
VCC2
M5282FP
IC1400
EP120
EP101
EP102
MAIN UNIT (1)
0.0047
C783
C364
0.0047
0.7mV
5.5mV
2.8mV
2.8mV
5mV
-7.64V
13.63V
4.9V
7.8V
TX: 0.2V
RX: 8V
TX: 7.96V
RX: 0V
13.6V
7.6V
-39.7mV
-39.6mV
13.63V
-90.1mV
12mV
12mV
6.73V
2.12V
12.93V
1.133V
TX: 3.88V
13.61V
TX: 0.329V
AM: 0V
other: 4.98V
0V
2.51V
2.52V
2.46V
2.49V
2.38V
3.9mV
-3.8mV
4.9mV
-2.8mV
-1.9V
-2.6mV
-1.6mV
PRE off,34dB
µ
(AGC on)
2.96V
PRE off,34dB
µ
(AGC on)
2.97V
1.625V
17.8mV
17.4mv
2.5mV
0.2V
HF: 0V
other: 0.377V
50M: 0V
other: 0.302V
144M: 0V
other: 0.38V
AM: 0V
other: 0.381V
0.847V
0V
144M
RX: 2.4V
144M
RX: 2.39V
144M
RX: 2.71V
144M
RX: 5.44V
144M
RX: 4.78V
144M
RX: 2.72V
1.43V
0.8V
2.7V
2.1mV
0.12V
7.8V
TX: 0.809V
TX: 1.2mV
7.85V
7.8V
8.7V
7.6V
0V
1.4V
0V
7.6V
7.0V
7.6V
3.7V
6.6V
0V
7.55V
1.282V
0V
1.282V
7.96V
7.79V
4.99V
-7.64V
0V
0V
7.8V
0V
3.1V
noise blanker
off: 7.79V
on: 0.775V
setting level
100%: 6.9mV
0%: 1.54V
0V
0.825V
2.68V
TX: -54mV
TX: 51.6mV
TX: 0.196V
TX: 1.2mV
TX: 17.5mV
TX: 7.04V
TX: 52.9mV
TX: -6.31V
TX: 4.77V
RX: 31mV
TX: 0.195V
RX: 0.64V
144M
TX: 0.195V
RX: 0.64V
144M
TX: 4.56V
RX: 29mV
HF+50M
TX: 4.76V
RX: 30mV
HF+50M
TX: 7mV
RX: 7.56V
HF+50M
TX: 0.195
RX: 0.64V
0.08V
0.65V
8.6V
0V
13.2V
0.1V
1.143V
7.39V
TX: 5.91V
TX: 0.328V
TX: 3.97V
TX: 5.96V
12.95V
3.3mV
4.35V
3.1V
4.34V
4.26V
-2.2mV
2.1mV
3.5mV
3.9mV
-39.7mV
2.0mV
4.9mV
8.8mV
4.62V
A
B
β
γ
α
C
D
E
Range
Digital tester
Voltage at RX(No designation)
MEASUREMENT CONDITIONS
frequency: 14.1MHz USB
RX(RF: no input)
TX(AF: no input)
200mV
2V
20V
Input resister
100M
Ω
11M
Ω
10M
Ω
OFF
L
M
H
13.66
Fan rotation
setting
A
12.17
11.97
11.67
13.65
B
11.51
11.28
10.951
0.70
C
1.32
3.41
4.98
0.50
D
7.53
9.66
11.24
0.002
E
0.723
2.81
4.36
1.9
Band
3.5
7
10
3.67
α
3.00
2.51
0.01
3.69
β
3.01
2.52
0.01
7.40
γ
6.05
5.00
0.01
14
2.01
2.02
4.06
18
1.58
1.589 3.18
21
1.58
1.589 3.18
24
1.10
1.119 2.22
28
1.10
1.119 2.22
50
0.935 0.940 1.88
144
0.932 0.936 1.87
12-3 MAIN UNIT (1)
Summary of Contents for IC-7400
Page 1: ...HF VHF TRANSCEIVER i7400 SERVICE MANUAL ...
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