![background image](http://html.mh-extra.com/html/icom/ic-2800/ic-2800_service-manual_612060045.webp)
R417
3.9k
MU/D
M8V
PTT
MICE
MIC
E
MDATA
T
D
ATA
R
D
ATA
GND
HV
IS2
IS1
IS0
II3
II2
II1
II0
EXTMIC
E8
SPE
MICUD
EXTMIC
SP
PTTP
LIMIT
LV
TONEIN
VSQL
VSOUT
USQL
USOUT
CLONEC
DTMF
TXDF
RXDF
CTCSS
Q4
Q3
Q2
Q1
TMAIN
STD
OPD
VDMUTE
UDMUTE
VAMUTE
UAMUTE
TONEIN
FANC
PTTM1
PTTP1
DMAIN
POWC
RESET
UMMUTE
VMMUTE
CLONEC
DTMUTE
PLSTB
MMUTE
STB
PSEL
CK
PSQL
DATA
UTX
VTX
RXD
W/N
UDMUTE
TXD
MW/N
VDMUTE
VSHIFT
3LB
4RX
1RX
UAM
ETONE
VAM
TXDF
PCTRL
DMAIN
TMAIN
CTCSS
UUNLK
ETONE
VUNLK
DTMF
RXDF
MRIPT
VCK
VDATA
DTMUTE
MMUTE
PTTP1
MRIPT
PTTM1
LIMIT
MW/N
SP
MICIN
R277
4.7k
R296 10k
R358
2.2k
R368
47k
R422
100k
R425
100
R426
680
R455
82k
R456
47k
C396
0.1
D49
[USA]
[Other]
PB0/AN0
1
PB1/AN1
100
VCC
76
PD0/SEG41
77
P97/SEG40
75
PD1/SEG42
78
AVSS
2
TEST
3
X2
4
X1
5
VSS
6
OSC1
7
OSC2
8
RES
9
NMI
10
P20/IRQ4/ADTRG
11
P21/SCK1
12
P22/SI1
13
P23/SO1
14
P24/SCK3
15
P25/RXD
16
P26/TXD
17
P27/IRQ0
18
P17/IRQ3/TMIF
19
P16/IRQ2
20
P15/IRQ1
21
P14
22
P13/TMIG
23
P12/TMOFH
24
P11/TMOFL
25
P10/TMOW
26
VSS
27
V3
28
V2
29
V1
30
VCC
31
P
A3/COM4
32
P
A2/COM3
33
P
A1/COM2
34
P
A0/COM1
35
P50/WKP0/SEG1
36
P51/WKP1/SEG2
37
P52/WKP2/SEG3
38
P53/WKP3/SEG4
39
P54/WKP4/SEG5
40
P55/WKP5/SEG6
41
P56/WKP6/SEG7
42
P57/WKP7/SEG8
43
P60/SEG9
44
P61/SEG10
45
P62/SEG1
1
46
P63/SEG12
47
P64/SEG13
48
P65/SEG14
49
P66/SEG15
50
P67/SEG16
51
P70/SEG17
52
P71/SEG18
53
P72/SEG19
54
P73/SEG20
55
P74/SEG21
56
P75/SEG22
57
P76/SEG23
58
P77/SEG24
59
P80/SEG25
60
P81/SEG26
61
P82/SEG27
62
P83/SEG28
63
P84/SEG29
64
P85/SEG30
65
P86/SEG31
66
P87/SEG32
67
P90/SEG33
68
P91/SEG34
69
P92/SEG35
70
P93/SEG36
71
P94/SEG37
72
P95/SEG38
73
P96/SEG39
74
PD2/SEG43
79
PD3/SEG44
80
PD4/SEG45
81
PD5/SEG46
82
PD6/SEG47
83
PD7/SEG48
84
PE0/SEG49/M
85
PE1/SEG50/DO
86
PE2/SEG51/CL2
87
PE3/SEG52/CL1
88
A
VCC
89
T
ONEM
90
T
ONED
91
VTREF
92
A
VREF
93
PB7/AN7
94
PB6/AN6
95
PB5/AN5
96
PB4/AN4
97
PB3/AN3
98
PB2/AN2
99
J5
1
2
3
4
5
6
7
8
R273
2.2k
R276
100k
D47
1SS355
R274
22k
R275
10k
C370
0.022
R459
1k
R460
1k
R461
100k
R281
100k
C371
0.022
C372
22p
C373
22p
X4
SMD-49
10.000 MHz
R465
1k
R466
1k
R469
1k
R470
1k
R299
1k
R297
1
C384
0.1
C383
47p
C382
47p
C381
47p
C380
47p
C379
47p
R308 1k
R481 1k
R316
1k
R318 22k
R319 39k
R495 1k
R499 1k
R332 1k
R334 1k
R502 1k
R503 1k
R507 1k
R506 1k
R508 1k
R509 1k
D56
D57
D58
D60
W13
C385
0.1
R341
470k
+
—
3
1
2
4
5
R342
390k
R343
120k
R344
12k
D63
MA8091
R407
1
R408
18
R409
390
C452
0.01
D64
MA8091
C453
10
+
C454
0.001
D65
1SS355
D66
1SS355
C391
47p
C455
0.001
R410
100k
R411
100
R412
10k
C456
10
+
R413
1.2k
1
2
3
5
4
C459
10
+
R445 6.8k
R447 220k
C461
0.22
R449
270k
R450
2.2M
R451
68k
R453
82k
C464
0.1
C463
0.1
R454
82k
R441
10k
C451
10
+
C450
100p
+
—
3
2
1
4
8
R440
100
R439
82k
C447
0.0027
C446
0.1
R436 820k
R435
560k
R434
220k
C445
10
+
R438
82k
R443
47k
[EUR], [ITA] only
R442
470k
[EUR], [ITA] only
R437
68k
R431
330k
R430 820k
C443 12p
C441
0.033
C442
1
+
R427
390
R428
47
R424
100k
C440
10
+
R429
390k
R423
22k
C439
0.001
C438
0.001
C437
0.1
C436
0.033
R421
330
R420
470k
R418
270k
R419
47k
C434
1
C435
0.1
R402
10k
C432
0.1
R403
1M
R404
2.2k
R405
10k
C433
0.1
R406
22k
R391
1k
C422
0.001
C423 1
R390
470k
R389
2.2k
R388
47k
R386 4.7k
C421
0.0056
C419
0.015
R387
22k
R384
470k
R385
330
C416
0.015
C415
0.01
C417
0.001
R383
39k
C418
0.033
R382
22k
R381
12k
R380
1k
C413
0.001
C414 1
R378
2.2k
R379
470k
C412
0.0056
R377
47k
R375
4.7k
C410
0.015
R376
22k
C420
0.0056
C411
0.0056
R374
330
R373
470k
C409
0.033
C408
0.001
C407
0.015
C406
0.01
R372
39k
R371
22k
R370
12k
D62
1SS355
C388
47p
C390
47p
C386
47p
L70 2.2 H
L71 2.2 H
L74 2.2 H
L75 2.2 H
L76 0.82 H
L77 2.2 H
L72 2.2 H
L73 2.2 H
C399
0.1
R354
1M
R353
82k
C398
0.039
R352
82k
R351
82k
C397
0.0015
C395
0.1
R349
470k
R350
120k
C394
0.1
R348
100k
R346
1M
R347
470k
C393
0.01
C392
100p
C404
1
R364
470k
R363
470k
R362
470k
R361
100k
C403
0.1
R369
22k
R366
470k
R365
470k
R367
470k
C402
0.1
D61
MA8062
C389
47p
C387
47p
R359
10k
C401
0.1
R360
22k
R357
1M
C400
0.1
R356
10k
R510
27k
C457
1
R415
4.7k
R416
3.9k Other
22k [USA]
J3
1
2
3
4
5
6
R282 1M
R513
100k
R514
2.2k
R515
22k
R516
10k
D73
1SS355
R500 1k
R501 1k
R518 1k
OUT
1
VDD
2
VSS
3
NC
4
CD
5
D74
DA202U
R519
15k
C470
0.01
R521
470k
R522
470k
R355
470k
+
3
2
1
8
C471
0.1
C472
0.1
R517 1k
Y1
1
Y0
2
Z1
3
Z
4
Z0
5
INH
6
VE
E
7
VS
S
8
C
9
B
10
A
11
X0
12
X1
13
X
14
Y
15
VDD
16
+
—
5
6
7
C374
0.001
R486
1k
CS
1
SO
2
WP
3
VSS
4
SI
5
SCK
6
HOLD
7
VCC
8
R523 100k
R525 100k
CP4
R511 5.6k
+
—
5
6
7
R532
390k
D67
MA728
C479
0.22
R414
100k
C458
0.001
R533
22k other
47k [USA]
only
I/O
1
O/I
2
O/I
3
I/O
4
CONT
.B
5
CONT
.C
6
VEE
7
I/O
8
O/I
9
O/I
10
I/O
11
CONT
.D
12
CONT
.A
13
VDD
14
D68
RB706F-40
W17
R294
4.7k
R542
10k
R543
10k
R295
4.7k
R291
15k
D75
DA202U
R489 1k
R320 82k
R322 150k
R488 1k
R317
10k
R337
1k
R504
1k
R505
1k
R464
100k
R462
100k
R467 1k
R468 1k
R289 1k
R287 1k
R336 1k
R491 1k
R496 1k
R494 1k
R497 1k
R498 1k
C511
0.001
R292
4.7k
C516
10
+
R321 330k
C377
10
+
C378
0.001
R298
470k
R463
100k
R482 1k
R483 1k
R485 1k
R477 1k
R478 1k
R305 1M
R479 1k
R480 1k
R476 1k
R304 1k
R474 1k
R284 1k
R471 1k
R300 1k
R475 1k
R473 1k
R310 1k
R484 1k
R487 1k
R323 1.2M
R324 680k
R313 1k
C405
1
R448
330k
C462
0.001
R452
120k
+
—
3
2
1
4
8
I/O
1
O/I
2
O/I
I/O
CONT
.B
5
CONT
.C
6
VEE
7
I/O
8
O/I
9
O/I
10
I/O
11
CONT
.D
12
CONT
.A
13
VDD
14
+
—
5
6
7
R328 1k
R492 1k [EUR], [ITA] only
R545
1k
R544
1k
R301
1k
EP2
MMZ1608Y102BT
W15
C505
470p
R490 1k
R3251k
R493 1k
C507
0.001
C508
0.001
C504
470p
C376
0.1
C510
0.001
C515
0.001
C519
0.001
C506
470p
EP3
MMZ1608Y102BT
R283
22k
[EUR], [ITA] only
R432
18k
C444
1
R433
47k [EUR],
[ITA] only
R549
47k
[EUR], [ITA]
only
C448
820p
C449
82p
R345
10k
VDET
VAF
UAF
VAFO
UAFO
UDET
—
3
4
CONTROL UNIT J2
MIC
INPUT
D50
D55
D52
D54
D51
D53
D59
DTMF UNIT
(OPTION)
4
PSQL
PSEL
R271
100k
C348
1
I/O
1
O/I
2
O/I
3
I/O
4
CONT.B
5
CONT.C
6
VEE
7
I/O
8
O/I
9
O/I
10
I/O
11
CONT.D
12
CONT.A
13
VDD
14
C349
1
R272
10k
C256
1
C284
1
PSQL
VSQL
MOD
1RX
4RX
DATA
CK
PLSTB
VUNLK
UUNLK
8V
HV
VTX
VSHIFT
UMMUTE
VMMUTE
UTX
C5V
LV
STB
VDET
POWC
3LB
CLONE
R203
1.5k Other
3.3k [EUR], [ITA ]
D1
1SS355
C3
1
R2
100k
C4
0.001
R49
470
D19
1SS355
R77
4.7k
C125
1
C126
0.001
R78
100k
3
2
1
R191
560
D40
MA8047
C249
0.1
X2
CDB450C24
R
1
C251
0.022
3
2
1
W7
C475
0.001
C12
100
R139
270
C250
47
+
R190
220
C24
0.00
1
C499
0.001
W8
R1
4.7k
DATAOUT
AFOUT
DATAIN
C5V
MAIN UNIT
OPD
Q1
Q2
Q3
Q4
STD
J6
1
2
3
4
5
6
7
8
9
10
R524
100k
OPD
GND
DETO
C5V
TOE
Q1
Q2
Q3
Q4
STD
IC19
HD6433876NB10H
HD6433876NB11H
Q78
2SC4081
IC24
TC75S51F
Q87
2SC4081
Q86
2SC4081
Q85
2SC4081
Q84
2SC4081
Q83
2SC4081
Q82
DTC144EU
Q81
2SC4081
Q96
2SC4081
IC16
S-80945ALMP-DA9-T2
IC20A
NJM4558M
IC29
BU4053BCFV
IC17
X25320SI-2.7
Q80
2SC4081
Q98
DTC144EU
Q79
2SA1576
IC21
BU4066BCFV
IC20B
NJM4558M
Q90
2SD999
Q91
DTA144EU Q92
DTC
114EU
Q93
DTC144EU
IC25
TC7S66FU
IC23A
NJM4558M
Q88
2SC4081
IC23B
NJM4558M
IC27B
NJM4558M
IC26
BU4066BCFV
IC27A
NJM4558M
Q89
2SC4116
Q73
DTC144EU
Q72
DTC144EU
IC13 BU4066BCFV
Q14
DTB1
Q17
2SC408
Q34
Q35,
Q37
Q34, 37: UMG9N
Q13
DTC144EU
Q
7.87
4.66
2.83
1.00
4.17
1.00
0.39
4.2
4.71
2.80
7.87
0.39
6.88
4.90
4.62
2.63
2.52
4.96
2.22
3.78
2.5
4.96
0.63
0.042
0.647
4.96
0.042
4.96
4.96
4.93
0.045
9.41
7.87
13.36
8.8
7.88
0.97
2.97
7.25
4.00
4.04
0.35
2.67
2.66
1.94
4.92
1.27
4.08
3.88
4.61
6.88
4.9
VR 0
VR
VR 4.6
VR 4.74