Icom IC-400PRO Service Manual page 34

MAIN UNIT (2)
a
6.8V
6.4V
C102
12p
b
Q11
2SC5107
Q10
6.0V 2SC5107
TX: 2.3V
RX: 2.2V
Q12
TX: 0V
2SC5107
RX: 3.0V
c
R8V
R8V
C49 L38
TX: 0V
5p 22n
RX: 7.4V
MAIN
UNIT
Q3
(1)
3SK299
C40
FI1
0.5p
FL-335
d C41
15p
TX: 0V
RX: 0.8V
BUS LINE1
R8V
VCC
VCC
C243 C245
0.0047 0.1
e
R246
R243
2 1.5k
82k - 1 SDEC
5V
3
+
R240 R242 IC16
C315
0.022 100k 39k NJM12902V
C321
0.1
IC16
R247 R248 R249 IC16
NJM12902V
NJM12902V
22k 22k 22k
R252
5
+
7 10 470
6 + 8 CDEC
- 9
-
C324
R250
470p
100k
R251
470k
4
V+ IC16
GND NJM12902V
11
5V
5V
CPU5V
CPU5V
8V
8V
BUS LINE2
T8V T8V
IC3
RA30H4452M-21
TX: 6.3V
RX: 0V
5
1 2 3 4
TX: 3.0V
C100 C331 C92 L18
RX: 0V
10p 0.5p 7p 15n
D14
1SV307
Q8
2SC3356
Q9
2SC5107
HV
L20
R66
27n
100k
FI4 FI3
NFM60R- NFM60R-
20T152 20T152
HV
T8V
R8V
R18
10k
C35 TX: 0V
Q1
0.1 RX: 0.5V
2SK1829
R206
470k
C343 TX: 0V
0.001
RX: 3.6V
RSSI
C30 C22
Q2
5p 0.5p
3SK293
TX: 0V
RX: 2.4V
R22 R14
10k 10k
R8V T8V
TX: 7.9V
Q25
RX: 0V
2SD1664
T8V
R304
22k
D23
DA221
Q29
DTC114TU
TMUT
7.9V IC9
Q26
TA7808F
2SA1577
R8V 8V
O I
G
TX: 0V
RX: 7.8V
Q30
R204 R205
DTC144EU
4.7k 10k
RXC
5.0V IC10
Q27
AN78L05M
2SA1577
5V CPU5V
O I
G
5.0V
6 5 4 Q24
DTC144EU
Q28
XP6501
R156
1 2 3
4.7k
POWER ON: 4.9V
OFF: 0V
5V
CPU5V
8V
T8V
C16
6 2p
L16 D2 C14 L3 L2
AS080340-15N UM9401F 47p AS100340-10N AS080340-15N
HV
HV
T8V
TX: 3.8V
RX: 0.2V
C79
TX: 3.8V 0.22
RX: 0.2V
R56
150k
R58
2
100 3
4
1
5
IC2
TA75S01F
C25 C19
2p 0.001
R323 D43
220k HVC350B
T8V
CPU5V
VCC
R287
10k
R194
2.2k
C249
0.0022
R193
470k
13.2V
1 5
4
3
Q23
2
2SJ377
IC15
TA75S01F
VCC
R200
HV
10k
R238
100k
HV
5V 5V
CPU5V CPU5V
8V
MEASUREMENT CONDITIONS
VOLTMETER
Amplitude(Oscilloscope) : 100 MHz
Frequency : 465 MHz
Transmission : 25 W
T8V
R3
47
L1
AS080340-15N
Explanatory notes
VOLTAGE LINE
TX LINE
RX LINE
R6 R5 COMMON LINE
10k 10k
HV
T8V
TX: 2.4V
RX: 2.0V
TX: 0V
RX: 4.8V
D28 R55
MA2S111 1k
R57
10k
AF ON: 4.5V
OFF: 0V
T8V
AFON
Q36
DTC144EU
Q35
DTC363EK
R197 C252
10k 0.1
AFO
VCC
R195 C251 C253
C256
2.7k 0.047 0.022
1 5 470
4
2
3
IC8
C246
LA4425A
0.1
AFO
VCC
HV
Q33
DTC144EU
Q39
DTC144EU
R322 C295 Q31 R225 C288
E 1 D 10 2SJ144 10k 0.1
R230
1k F
R224 C289
47 0.1
R226 D26 R223
100k MA2S111 1k
5V
4.4V
11 - 3
J1
W1
J4
J7 P1
+
-
CHASSIS
SP1
EP4
HV
EP5 W2
J6
VCC
GND
DIM
HORN
GND
AFO
GND
to
OPC-617
DISC
GND
IN
GND
PTT
GND
W3