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12 - 5
12-5 PA UNIT, FILTER, DRV AND VARISTOR BOARDS
R1
R2
NTCCM16084LH
R1,R2
14V
HV
5V
THML
H5V
8V
14VS
H14V
0.1
C95
18k
R103
68k
R104
C402 47p
C403 47p
VRX
J121
unit
to RF
P601
J601
VRX
ACS2
ACS1
HV
GND
HV
GND
10
R503
1.9MHz
3.5MHz
18/21MHz
C591 33p
10/14MHz
24/28MHz
7MHz
50MHz
0.001
C118
W8
W7
F1
F2
C32 0.001
470
C20
0.0047
C117
47p
C99
R16 1
C11 0.047
LA-264
L208
220
R74
C217 47
C1 0.1
R1
R2
J21
J23
J24
J22
J202
J201
J102
J101
EP1
EP2
V-T2
18k
R251
18k
V-T1
R101
DAP202K
D101
CP223
CP217
ANT]
[144MHz
CHASSIS
J7
W12
W13
EP7
H14V
GND
EP4
EP5
CHASSIS
P1
4
5
6
1
2
3
V-A1
DRI1
GND
DRI1
GND
GND
DRI1
GND
DRI1
GND
DRI2
GND
DRI2
DRI2
GND
DRI2
GND
GND
DRO2
GND
DRO2
DRO2
GND
DRO2
GND
DRO1
DRO1
GND
GND
DRO1
DRO1
GND
GND
DRV BOARD
V-A2
GND
V-A1
V-A2
GND
V-T1
V-B2
GND
V-B1
V-T2
GND
V-B2
1
R4
1
R3
1
R2
1
R1
22p
C3
2SK2975
Q2
2SK2975
Q1
100
R6
100
R5
150
R11
0.1
C2
68
R8
68
R7
0.1
C1
VARISTOR-D BOARD
MA30PXB
D1
EP1
V-B2
GND
V-T2
NTCCM16084LH
R1,R2
VARISTOR-C BOARD
MA30PXB
D1
EP1
V-B1
GND
V-B2
V-T1
GND
V-A2
EP1
MA30PXB
D1
VARISTOR-B BOARD
VARISTOR-A BOARD
V-A2
GND
V-A1
EP1
MA30PXB
D1
EP3
EP2
220p
C102
0.1
C24
18
R17
W29
CP145
CP146
R71 1
C116 200p
C35 200p
C115 200p
C114 200p
C100 200p
CP117
CP22
CP21
C107 0.1
R10 2.2k
C18 0.1
0.047
C19
4.7
R73
R70 100
3.3
R24
3.3
R21
C110 200p
200p
C111
CP226
PWRS
GND
2SD1585K
Q203
C211 47p
C235 22p
C234 24p
C233 22p
0.0047
C5
0.0047
C6
C2 0.1
LR-393
L18
C7 0.1
C29 0.001
C119 0.001
C8 0.1
0.0047
C16
56
R622
EXC-ELDR25C
L8
LR-386
L1
CP12
CP11
CP10
CP9
CP8
CP7
LR-386
L2
0.1
C12
0.1
C9
0.0047
C10
0.0047
C13
CP6
CP5
CP4
CP3
CP2
CP1
CP215
CP203
CP204
CP206
CP207
CP205
CP208
DRES
YGR
PA UNIT
FSTB
OUT2M
OUT2M
MDAT
5V
MCK
14VS
VFOR
VREF
J1
unit
to CTRL
P501
J1
C5 0.1
J502
ICL
LR-411
L13
LR-383
L10
T8V
EXC-ELDR25C
L12
ICH
PWRS
L8
VPAO
L8
HPAO
EP6
BU4094BCF
IC502
TD62783AF
IC501
QS
Q'S
Q8
Q7
Q6
Q5
VDD
OENA
9
10
11
12
13
14
16
15
VSS
Q4
Q3
Q2
Q1
CLK
STRB
DATA
GND
O8
O7
O6
O5
O4
O3
O1
O2
VS
IN8
IN7
IN6
IN5
IN4
IN3
IN2
IN1
10
11
12
13
14
15
16
17
CP505
470
R401
47k
R501
C620 0.1
18
R402 470
R403 470
R404 470
C404 47p
C618 0.1
R502 4.7
CP503
W601
CP513
CP514
W602
R606 10k
C614 220p
R601 82
HSU88
D603
C612 220p
R605 220
0.0047
C626
47
R617
0.001
C622
56
R615
R604 5.6k
C613 220p
R602 82
HSU88
D602
C611 220p
R603 1k
CP502
C609 18p
C607 27p
C605 33p
C602 18p
10
µ
L522
10p
C608
3p
C606
1p
C604
LA-176
L603
LA-177
L602
LA-177
L601
DTC114EU
Q605
DTA114EU
Q604
0.0047
C627
CP511
L1
L3
(b)
L6
L2
L4
L5
0.001
C601
C610 0.001
CP210
DTC114EU
Q602
0.001
C621
56
R616
DAP222
D601
MA8039
D620
56
R614
C616 0.001
1.2
µ
L604
470
R618
0.0047
C624
0.001
C623
2
0.0047
C625
1.2
µ
L605
470
R619
100
R620
100k
R621
1SV265
D605
AE5349
RL601
9
8
7
6
5
4
3
1
2
FILTER BOARD
100
L513
100
µ
L519
W504
10
µ
L518
10
µ
L533
C598 0.001
C572 390p
C573 390p
C597 0.001
C574 820p
C575 820p
C554 220p
C503 330p
180p
C502
C600 560p
C505 120p
LR-294
L501
LR-295
L502
C599 0.001
C507 330p
C566 330p
C567 270p
C508 100p
C568 270p
C569 120p
430p
C510
110p
C512
LR-216
L503
LR-214
L504
C514 390p
C515 270p
C532 120p
C555 15p
C534 220p
C561 47p
18p
C533
C535 56p
L509 LA-481
L510 LA-551
C536 82p
C557 120p
C528 120p
C531 150p
C558 120p
110p
C530
56p
C563
LR-293
L507
LR-293
L508
LR-293
L528
C537 120p
C589 33p
C539 100p
22p
C540
LR-387
L534
7p
C538
LR-388
L512
LR-388
L511
C541 33p
C18 0.1
C15 0.1
C565 82p
C516 180p
C517 270p
C525 330p
C521 270p
C520 330p
C524 330p
100p
C518
22p
C522
LR-216
L505
LR-216
L506
C523 330p
C577 22p
C578 39p
C579 39p
C582 22p
C581 82p
C583 4p
C585 10p
C586 22p
LA-550
L529
LA-548
L530
LA-547
L531
(d)
C542 0.0047
C547 0.0047
C401 47p
CP212
TB1-160
RL501
C544 0.0047
AG201344
RL514
1
3
4
5
C588 0.0047
TB1-160
RL503
C550 0.0047
100
µ
L517
10
µ
L524
TB1-160
RL506
10
µ
L521
TB1-160
RL509
C549 0.0047
C548 0.0047
TB1-160
RL512
TB1-160
RL507
C552 0.0047
C553 0.0047
TB1-160
RL508
10
µ
L523
TB1-160
RL511
C546 0.0047
TB1-160
RL505
C587 0.0047
TB1-160
RL510
T8V
10
µ
L532
C551 0.0047
T8V
AG201344
RL513
C83 0.0047
0.0047
C89
C82 0.0047
C88 0.0047
(a)
C543 0.0047
(c)
L7
C84 0.0047
(d)
W1
2
1
3
4
5
6
7
0.0047
C81
8
(b)
(c)
(a)
TB1-160
RL502
HV
14V
14V
14V
14V
14V
14V
14V
14V
14V
ICH
ICL
GND
GND
VFOR
VREF
GND
T8V
GND
8V
8V
THML
H5V
5V
5V
MCK
MDAT
FSTB
DRES
PWRS
C90 0.0047
C91 0.0047
CP213
CP118
LA-262
L20
CP214
C545 0.0047
L535
LA-267
CP216
CP218
CP219
CP209
CP220
J5
J120
unit
MAIN
to
(5A)
FGB
F3
100
µ
L515
EP3
PGND
P14V
EP2
C85 0.0047
C86 0.0047
TA78L05F
IC1
G
O
I
C72 10
C71 0.1
C70 0.1
C69 10
TB1-160
RL504
C39 1000
C40 1000
C41 0.1
C42 0.0047
C79 0.1
DAP222
D7
0.0047
C80
UN9211
Q9
JV-12-KT
RL1
EXC-ELDR25C
L22
EXC-ELDR25C
L23
R31 1k
C44 0.0047
R29 1k
R28 5
C43 0.0047
C78 0.1
CP114
R38 4.7
L19 LR-230
C92 1000
C215 220p
C214 220p
C213 0.047
C241 2.2
LW-33
L205
LA-179
L204
CP222
CP221
CP104
LA-300
L206
C208 200p
C212 10p
C239 2p
C238 2p
27p
C590
C1 0.0047
C210 10p
CP227
LR-83
L17
CP116
J10
C73 0.0047
TA7808S
IC3
G
O
I
C77 10
C76 0.1
C75 0.1
C74 10
TA7805S
IC2
G
O
I
C68 100
C67 0.1
C66 0.1
C65 100
3.9
R44
D5 DSA3A1
D4 DSA3A1
D8 DSA3A1
C46 1000
C103 220p
C47 0.1
C45 0.047
DTC114EU
Q14
DTC114EU
Q15
DTA114EU
Q16
R61 5.6k
470
R19
EVM-2A
R18
2SD1585K
Q7
C48 0.1
C49 47
CT IN
EXC-ELDR25C
L14
2SC5125
Q5
2SC5125
Q6
4.7
R42
0.68
R34
4.7
R41
0.68
R35
10
R27
10
R26
0.68
R33
0.68
R32
0.0047
C19
R23 4.7
EXC-ELDR25C
L16
C105 0.001
EXC-ELDR25C
L15
C33 0.001
R20 4.7
0.001
C31
R202 10
560
R62
CP225
CP224
100
µ
L21
C87 0.0047
DAP222
D11
NA-12W-K
RL2
EXC-ELDR25C
L207
DTA114EU
Q205
DTC114EU
Q204
390
R203
EVM-2A
R204
C216 220p
C221 220p
R205 12
C222 47
EP201
L201 LW-9
C203 6p
50p
C202
10p
C201
10p
C237
10
R201
LA-263
L203
LA-263
L202
2SC2694
Q202
2SC2694
Q201
C228 68p
C229 68p
C230 68p
C231 68p
C226 68p
C225 68p
C224 68p
C223 68p
14V
T8V
L8
L8
H14V
EXC-ELDR25C
L11
H14V
T8V
H14V
R11 EVM-2A
R12 22
C54 47
C52 0.1
C16 0.001
C120 47
C15 0.1
EXC-ELDR25C
L6
LR-410
L7
4.7
R7
R63
220
470p
C98
R6 220
2SC1971
Q2
470
R9
0.0047
C14
390
R5
C13 0.001
C12 0.1
R8 330
R60 100
0.001
C7
0.1
C6
L2 100
µ
LR-355
L1
C9 0.001
C8 0.1
2SK2973
Q1
470
R4
C3 0.1
10
R3
0.001
C4
680
R2
R1 4.7K
C2 0.001
330
R703
15
R702
330
R701
from/to RF
unit J151
C30 0.1
P1
W3
V-A1
PA UNIT
TX: 1.2V
RX: 0V
POWER ON: 5V
OFF: 0V
POWER
ON: 13.8V
OFF: 0V
POWER ON: 7.9V
OFF: 0V
POWER
ON: 7.9V
OFF: 0V
POWER
ON: 0V
OFF: 13.84V
HF+50M
144M
TX: 9.0V
RX: 0V
POWER
ON: 13.8V
OFF: 0V
TX: 13.2V
RX: 0V
TX: 10.4V
RX: 0V
TX: 11.3V
RX: 0V
13.8V
TX: 8V
RX: 0V
TX: 0.01V
RX: 13.8V
7.9V
5V
13.8V
HF+50M
TX: 1.35V
RX: 0.3V
HF+50M
TX: 0.68V
RX: 0V
HF+50M
TX: 7.9V
RX: 0.3V
HF+50M
TX: 0.65V
RX: 0V
HF+50M
TX: 0.65V
RX: 0V
144M
TX: 7.9V
RX: 0V
144M TX: 1.378V
RX: 0.25V
TX: 2.54V
RX: 0V
TX: 0.58V
RX: 0V
144M TX: 0.68V
RX: 0V
13.8V
144M
TX: 0.7V
RX: 0V
13.8V
13.8V
13.8V
TX: 1.96V
RX: 0V
13.8V
13.8V
RX: 13.8V
TX: 2.7V
RX: 0V
TX: 2.7V
RX: 0V
RX: 13.8V
L1
11.78
Selected
11.78
11.78
11.78
11.78
11.78
12.00
12.00
L2
L3
L4
L5
L6
L7
L8
Frequency(MHz)
0.03000
∼
1.99999
2.00000
∼
4.99999
5.00000
∼
7.99999
8.00000
∼
14.99999
15.00000
∼
21.99999
22.00000
∼
29.99999
30.00000
∼
60.00000
108.00000
∼
174.00000
Range
Digital tester
MEASURMENT CONDITIONS
frequency:14.1MHz USB
RX(RF: no input)
TX(AF: no input)
Voltage at RX(No disignation)
200mV
2V
20V
13.8V
Input resister
100M
Ω
11M
Ω
10M
Ω
Summary of Contents for IC-7400
Page 1: ...HF VHF TRANSCEIVER i7400 SERVICE MANUAL ...
Page 63: ...to S LOGIC board J303 DS1002 9 2 DISPLAY BOARD TOP VIEW 9 3 for free by RadioAmateur eu ...
Page 72: ...9 12 1 9 18 10 BOTTOM VIEW RF UNIT for free by RadioAmateur eu ...
Page 74: ... BOTTOM VIEW CTRL UNIT 9 14 for free by RadioAmateur eu ...
Page 76: ... BOTTOM VIEW TUNER UNIT 9 16 for free by RadioAmateur eu ...
Page 78: ...9 18 BOTTOM VIEW PA UNIT for free by RadioAmateur eu ...
Page 92: ...1 1 32 Kamiminami Hirano ku Osaka 547 0003 Japan S 13811HZ C2 2002 Icom Inc ...