Icom IC-A25C Service Manual

9-5
TX Line
RX Line
Voltage Line
Explanatory notes
INTPTT
J6
12
34
56
78
910
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 50
IC5
STR
D
CLK
Q1
Q2
Q3
Q4
GND QS
Q'S
Q8
Q7
Q6
Q5
OE
V+
GND
V+
VREF
SENSE
INT
GAINSW
IN
IC215
GAIN1
GAIN2
DET
OUT
BUFFIN
BUFFGAIN
BUFFOUT
NJU72341V
IC229
NC
NC
IN1
IN2
MUTE
SDA
SCLV+
VREF
GND
OUT2
OUT1
NC
NC
IC231
COM
INH
VEE
GND A
CH1
CH0
VCC
TC7W53FK
COM
INH
VEE
GNDA
CH1
CH0
VCC
IC221
Shutdown
VREF
MODE
VIN VOUTP
VDD
GND
VOUTN
CD4094BPWR
1
2
3
4
5
6
7
89
10
11
12
13
14
15
16
+5V
R231
0
47k
R317
R212
47k
0.001 C333
0.001
C274
DMG564050
Q52
1
2
3
4
5
6
0.001
C293
J5
1k
R227
R213
39k
22k
R316
100k
R417
0.047
C225
R211
180k
0.001
C491
1
C294
220
C538
0.001
C539
J4
1
2
34
SP1
W10000
1
2
R140
100k
NJM2904CRB1
IC223
1
2
3
4
5
6
7
8
NJM2904CRB1
IC224
1
2
3
4
5
6
7
8
NJM2904CRB1
IC225
1
2
3
4
5
6
7
8
NJM2904CRB1
IC226
1
2
3
4
5
6
7
8
R214
820k
NJM2904CRB1
IC222
2
3
1
NJM2904CRB1
IC222
V+
8
GND
4
IC228
1
2
3
45
6
7
8
0.1C202
0.1
C331
1
2
3
4
5
6
78
9
10
11
12
13
14
1
C566
1
C567
1C568 0.1C569
0.1C570
10
C571
10
C572
0
R502
VCC
+3V
MPZ2012S331A
EP6
L2SA1576AS
Q50
MPZ2012S331A
EP7
0.001
C240
0.047
C239
R220
470
0.001
C237
MPZ2012S331A
EP5
0.001
C243
R223
10k
0.001
C241
L1SS400
D36
R222
220k
DA3S101F0
D23
R108
18
0.001
C127
R109
10k
DRC9114E0
Q26
D27
L1SS400
R148 1k
DMC501010
Q36
1
2
3 4
5
R142
0
R150 100k
Q35
2SB1201
1k
R526
F6027AP
MC1
470P
C58
7
47P
C588
DZ2J051M
D71
33k
R527
LDTC144EE
Q226
2.2k
R528
100
R529
0.001
C656
TPD1E10B06
D72
MPZ2012S331A
EP11
MPZ2012S331A
EP24
L1SS400
D52
0.001
C544
0.001
C543
MPZ2012S331A
EP23
MPZ2012S331A
EP10
BLM15BD102SN1 EP25
BLM15BD102SN1
EP26
0.001
C593
0.001
C596
0.1
C597
1
C598
22
R501
RB886CS
D59
10
C121
10
C608
0.1
C196
0.1C187
TC7W53FK
1
2
3
45
6
7
8
1k
R542
RB886CS
D74
1M
R546
RSR025N03
Q232
LDTC114EE
Q233
470k
R548
0.1
C627
100k
R564
100k
R565
1k
R568
0.1
C628
Q25
2SB798
100
C130
4.7
C238
100k
R569
J2
0.01
C330
820P
C557
820P
C558
150P
C559
470P
C561
0.0047
C560
100P
C563
0.0039
C562
0.01
C564
15P
C565
0.0022
C551
0.0033
C553
0.1C633
0.1
C634
0.1C635
0.1
C636
0.1
C637
NJM2904CRB1
IC222
6
5
7
0.1
C638
0.001
C639
0.001
C640
0.1
C242
R225
10k
0.1
C641
100k
R594
100k
R595
0.1
C642
15k
R540
330k
R541
0.018
C623
0.018
C622
NJM2904CRB1
IC232
2
3
1
NJM2904CRB1
IC232
6
5
7
NJM2904CRB1
IC232
V+
8
GND
4
0.1
C643
0
R532
180k
R283
1k
R596
10k
R318
NJM2783V
1
2
3
4
5
6
78
9
10
11
12
13
14
33kR500
4.7k
R499
330k
R545
56k
R544
2.2M
R543
470P
C644
0.1
C645
LDTC144EE
Q236
1k
R600
47k
R623
47k
R622
47k
R624
100
R620
0.1
C624
0.47 C223
SKHLLCA010 S1
1
C589
100k
R645
100k
R644
100k
R646
0.1
C245
100k
R647
100k
R648
0.1
C661
0.1
C662
0.1
C664
LMV321IDCK
IC233
1
2
3
4
5
1M
R597
47k
R319
*C631
4.7k
R626
4.7k
R621
47k
R627
47k
R629
47k
R632
1.8k
R530
0.47C188
56k
R549
0.1
C666
0.001
C667
0.001
C668
0.001
C669
0.001
C670
100P
C671
100P
C672
0.001
C420
0.001
C673
0.001C674
0.001
C675
0.047
C197
27k
R656
220k
R657
*C549
*C550
*C552
*C554
*C632
*C555
R147
12k
ISD8102SYI
1
2
3
45
6
7
8
9
R660
100k
1k
R662
0.001
C683
0.001
C684
0.1
C542
1C541
R107
330
270
R671
560k
R498
R226
22k
0
R349
R210
0
18k
R563
R224
15k
0
R593
18k
R443
33k
R566
33k
R497
4.7k
R677
100k
R678
22k
R680
LDTA144EE
Q245
LDTC144EE
Q246
R145
10k
*R478
*R479
*R480
100k
R481
100k
R482
100k
R483
100k
R484
100k
R485
100k
R486
270k
R487
560k
R488
270k
R489
56k
R490
68k
R491
100k
R492
120k
R493
120k
R494
120k
R495
100P
C591
100P
C592
0.001
C590
PDATA
MOD
MOD
AFDET
OE
RFSTB
CLONE
EXTPTT
PTT
ANLC
R5C
WXC
ALCC
JACKDET
SDATA
SCK
OE
VOLCLK
VOLDATA
UNLK
SCK
SDATA
PSTB
PCK
DA1STB
DA2STB
MMUTE
PCON
PTT
PWRBTN
PWSW
RFDETV
RSSI
SBATT2
VIN
VORDET
VORON
DCIN
NOISE
BEEP
EMBI
BATDATA
CLONE
AGCOFF
MOD90O
MMUTE
EXTREGC DETMUTE
DETO
BTMICSW
BTMIC BTMICSW VOX
BTAF
RFSTB
VOX
MOD90I
BTAF
NARROW2
AFC
AFC
TXC
TXC
SPMUTE
SPMUTE
BTMIC
INTPTT
VOLI VOLO
VCC
VCC
VCC
SPMUTE
+5V
+5V
NARROW
BEEP
DETO
EMBI
ALCC
PATMP
LVIN
JACKDET
CHGC
CHGIH
EXTREGC
VOLCLK
VOLDATA
AFON
+3V
+3V
+3V
AF5V
AFC
HV
5.0 V
• MAIN UNIT (3/4)
*Refer to the PARTS LIST for the value and name of component.

Icom IC-A25C Specifications

General

Purpose	Aviation Service (Air Band)
Operating frequency	118.000 – 136.992 MHz
Display type	LCD
Display diagonal	2.3 \
Battery type	BP-288
Battery life (max)	10.5 h
Battery low indication	Yes
Number of batteries supported	1
Product color	Black
Operating temperature (T-T)	-10 - 60 °C
Number of batteries included	1 pc(s)
Antenna connector type	FA-B02AR

Weight and Dimensions

Depth	31.8 mm
Width	58.9 mm
Height	148.4 mm
Weight	384 g