![background image](http://html1.mh-extra.com/html/icom/ic-f2721/ic-f2721_service-manual_4223366047.webp)
COMMON LINE
IC37
TA75S01F
MAIN UNIT
C417
1
HV
R332
10k
C482
0.001
C474
47p
C455
0.001
Q39
DTC144EUA
Q38
DTC144EUA
C453
0.001
C423
0.1
C452
0.001
C424
0.1
R336
10k
R337
47
R335
1k
R307
1M
R334
100k
R333
1M
D39
MA2S111
Q33
2SJ144
C395
10
R301
100k
R306
220k
R302
220k
C485
0.001
C477
470
C475
47p
C476
0.001
R360
10k
R372
300k
R373
100k
C459
470
C457
0.1
R359
4.7k
R339
4.7k
R338
4.7k
C429
10
Q34
2SD1664
Q35
DTC114TUA
C422
0.001
D37
DA221
C430
0.1
C428
10
C397
0.001
R311
10k
R310
4.7k
Q30
2SA1577
C398
0.001
C396
10
Q27
DTC144EUA
Q32
XP6501
1
2
3
4
5
6
R308
22k
R309
22k
C400
0.001
C399
10
C454
0.001
R361
470
Q41
DTC144EUA
C478
0.1
C458
10
C460
0.1
R312
2.2k
C387
0.001
C420
1
C418
1
C421
1
C419
1
R305
1k
R469
100
C580
0.1
C394
0.1
C393
47
IC36
TA7808F
I
O
G
IC40
AN78L05M
I
O
G
Q42
2SJ377
L41
4.7H
R371
10k
R374
10k
Q40
DTC144EUA
EP10
EP11
CP21
CP24
CP25
CP27
CP28
J8
1
2
3
4
5
6
7
8
9
10
11
12
13
IC35
DS14C232TM
1
C1+
2
V+
3
C1–
4
C2+
5
C2–
6
V–
7
DOUT2
8
RIN2
9
ROUT2
10
DIN2
11
DIN1
12
ROUT1
13
RIN1
14
DOUT1
15
GND
16
VCC
Q44
DTC363EK
R377
10k
D49
MA2S111
C486
0.47
R391
100k
R378
22
D46
DSA3A1
D57
DA221 TL
D58
DA221 TL
D59
DA221TL
D60
DA221 TL
Q31
2SB1132
R419
10k
R420
47k
R436
47k
CP41
CP42
CP43
CP43
CP43
CP44
CP44
CP44
CP45
CP46
CP52
CP53
R439
1k
R440
1k
DC cable
W3
OPC-1414
D66
DA221 TL
D67
DA221 TL
CP55
CP56
CP56
25 pin
CONNECTOR
EEPROM
Connector
Flash for
MAIN CPU
DIGITAL CPU
J13
1
2
3
4
5
6
7
8
9
10
C366
10
DIM
HORN
DISC
F
SIG
SIGO
PWR
T8V
T8V
BATV
EPTT
PGI1
PGI1
PGI3
PGI3
PGO1
PGO1
R8V
R8V
PA
2
CPU5
CPU5
IGSW
IGSW
TXD
TXC
TMUT
VCC
VCC
VCC
VCC
VCC
VCC
VCC
VCC
VCC
HV
PGI2
PGI2
D48
DAN222TL
D44
DAN222TL
D47
DAN222TL
R370
100k
CTS
TXD
RXD
RXD
ARXD
CTSI
XCTS
RTS
MD2
TXD2
RXD2
C_RES
TXD
RXD
RDAT
RCK
MD1
MD1
ARES
ARES
ARES
MD1
MD2
GND
GND
C_RES
RXD2
TXD2
ARES
MD1
MD2
C_RES
RXD2
TXD2
AT
X
D
XR
TS
8V
8V
8V
8V
8V
Q43
DTC144EU
J7
1
2
3
4
5
6
7
8
9
10
NTXD
NRXO
NTXD
NRXO
PGO2
PGO2
GND
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
RCK
CTS
RTS
RDAT
RXD
TXD
HANG
HANG
MMUT
MMUT
BUSY
VCC
RCK
VCC
3VA
3VA
MD1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
C83
0.001
C547
0.001
C541
12p [H]
8p [L]
C542
6p [H]
10p [L]
C121
1
C569
47p
C122
470p
C125
47p
C161
0.1
C545
0.001
C120
0.001
R97
22k
R128
100k
C540
0.5p
C84
0.001
CP9
R431
22k
R458
10k
FINRF
OUT1
FINRF
OUT1
R457
100
R432
1.2k
R433
2.2k
C522
3.3
C523
0.47
R430
5.6k
C525
0.0033
R83
4.7k
C548
47p
R79
10k
R77
100
R129
100k
5V
C129
0.001
C162
10
X4
CDBC450KCAY24
R131
680
R132
100k
1
OSCIN
2
OSCOUT
3
MIXOUT
4
VCC
5
IFIN
6
DEC
7
FILOUT
8
FILIN
AFOUT
QUAD
IFOUT
RSSI
N-DET
N-REC
GND
MIXIN
R130
1.8k
R455
1k
R428
1k
R459
1.5k
R80
330
R149
100k
C124
1
L13
1.2H
D11
HVC350
TXC
VCC
OPC-617
DIM
HORN
GND
AFO
GND
DET
GND
IN
GND
PTT
T8V
R8V
HV
CPU5
CPU5
5V
8V
8V
CPU5
5V
8V
CPU5
5V
5V
5V
5V
5V
5V
5V
5V
T8V
R8V
8V
CPU5
5V
5V
5V
5V
8V
C549
47p
L21
33nH
C260
47p
C256
0.001
R212
220k
Q19
2SC5107
R193
470
C242
470p
Q4
2SK880
L50
0.82H
C190
5p [L]
7p [H]
C226
8p
R178
JPW
R148
5.6k
R175
6.8k
Q12
2SC4226
C221
0.001
C223
47p
C586
0.1
C218
7p [H]
12p [L]
R173
JPW
C217
18p [H]
12p [L]
R147
6.8k
R174
6.8k
Q11
2SC4226
C220
0.01
C222
470p
C576
0.1
C577
0.1p
EP6
ACZ1005Y-102-T
EP9
ACZ1005Y-102-T
C240
0.5p
C239
0.5p
R362
100k
C461
2p [H]
3p [L]
W2
ANT
C431
0.001
R340
47
R342
100
R315
47
D40
MA728
D38
MA728
C402
10p [H]
7p [L]
C401
0.001
R313
100
C389
2p [H]
3p [L]
C388
2p [H]
3p [L]
C374
0.001
D30
UM9401F
[F2721D],
[F2821D]
only
D29
XB15A407
[F2721D],
[F2821D]
only
C346
3p
C357
47p
C534
22p
C533
47p
C377
47p
C347
22
C327
4p
C326
3p [H]
4p [L]
C356
470p
C355
22
C353
47p
C354
0.001
R363
4.7k
R364
8.2k
R344
220k
R346
220k
R347
390k
R343 150k
R318
220
R316
100
R319
68k
[F2721/D],
[F2821D]
only
C463
47p
C462
0.001
C438
0.0047
R345
10k
C436
1
C434
0.22
C406
0.01
C405
0.001
C392
0.001
C407 0.001
[F2721/D],
[F2821D]
only
Q36
2SC4116
[F2721D], [F2821D] only
1
2
3
4
5
C435
47p
C404
47p
C383
0.3p
D35
1SS375
R303
10k
R317
270k
C382
0.001
C358
10
C333
2.2
C332
47p
R281
330
R294
10k
R275
150
R299
100
R293 1.8k
C575
1.5p
C290
0.001
C323
0.001
C324
47p
C285
47p
C282
0.001
C280
4p [H]
10p [L]
C281
0.01
R242
100
R251
100
R283
100k
R282
100k
R284
10k
R247
4.7k
R239
100
R240
100k
R238
10k
R210
33
R237
100
R211
68k
C279
47
C259
5p
Q22
2SC5107
C288
47p
C287
18p [H]
10p [L]
R246
1k
R245
10k
R208
120k
R209
100
VC0V
C255
47p
L22
617DB-1327=P3
L23
617DB-1327=P3
D16
HSB88WS
Q14
PMBFJ310
Q13
PMBFJ310
L17
4.7H
C107
0.1
C87
3p
R85 47
R451
6.8k
R194
10k
VCOV
8V
R453
4.7
R454
820 [H]
680 [L]
R452
6.8k
R86
1.5k
R105
470
C130
0.1
C131
330p
C133
0.001
C134
0.001
C168 0.001
C166
47p
C557
0.001
C163
100p
C164
100p
L18
0.27H
C228
0.01
C229
0.001
C230
0.01
R184
22
L19
4.7H
C245
2p
C269
10p [H]
9p [L]
C270
0.001
C271
7p [H]
9p [L]
C294
0.001 [H]
0.01 [L]
C247
0.001
C292
1
C578
47p
C293
0.001
C291
0.001
C302
0.001
R218
220k
R219
220k
R220
10k
R257
4.7k [H]
1k [L]
R252
10
L31
12nH [H]
15nH [L]
R258
270
R253
4.7
R254
56k
R255
10
C303
0.001
C304
47p
C295
0.001
Q24 3SK293
Q6
2SC4215
R151
1.5k
C165
0.001
C199
0.001
C198
0.01
R177
10k
R256
18k
R278
1.8k
R280
10k
R279
470k
D31
UM9401F
D28
MA728
D27
MA77
C385
5p [H]
8p [L]
L37
33nH
L36
18nH [H]
22nH [L]
L32
18nH [H]
22nH [L]
C298
7p
C334
8p
C331
3p [H]
2.5p [L]
C363
8p
C297
0.1
C300
0.001
C296
0.1
C299
0.1
C330
0.1
A01
C359
7p
Q26
2SK1829
D22 MA2S111
D25
DA221
D24
MA2S111
D17
HVC350
D18
HVC350
L28
15nH
C364
68p
C361
18p [H]
24p [L]
C336
0.001
C335
18p [H]
24p [L]
C362
0.001
D26
HVC350
D68
HVC350
D69
HVC350
D23
HVC350
C360
0.001
D20
MA77
Q21
2SC5107
C263
47p
R217
8.2k
L29
27nH
L27
27nH
R215
8.2k
R213
100 [L]
10 [H]
C262
47p
Q20
2SC5107
C167
0.001
C153
47p
C155
0.01
C550
47p
C241
0.1
C243
47p
C257
0.001
C289
1p
C284
470p
C322
47p
C321
3.5p [L]
5p [H]
C403
47p
C433
0.001
D19
1SV307
D41
MA2S728
FI5
NFE31PT152Z1E9L
1
2
3
FI6
NFE31PT152Z1E9L
1
2
3
FI7
NFE31PT152Z1E9L
[F2721/D],
[F2821/D] only
1
2
3
IC12
TA31136FN
9
10
11
12
13
14
15
16
L25
33nH
L35
15nH
L38
1H
L43
15nH
L42
15nH
L44 15nH
L49
15nH
Q9
2SC4116
Q16
2SC4226
Q17
XP1214
1
2
3
4
5
Q18
DTC144EUA
Q23
2SC5107
Q48
2SC3356
R127
2.2k
R314
27k [H]
39kp [L]
R341
39k
R181
6.8k
R180
100
C201
0.001
C205
0.001
C200
0.01
R375
100
R376
6.8k
R155
1k
L40
15nH
C487
0.1
L6
1.2H
C227
33p
C283
3.5p [L]
4p [H]
C325
3p [H]
4p {L]
C571
0.3 [H]
L30
27nH
R248
27k
R443
47
L33
27nH
L56
6.8nH
R214
220
C261
6p [H]
10p [L]
L24
18nH [H]
27nH [L]
L26
18nH [H]
27nH [L]
R99
4.7k
R101
2.2k
Q10
2SC4215
C345
3p
C373
5p
C375
1p [H]
3p [L]
C376
2p
C391
3p [H]
5p [L]
C551
3p [H]
4p
[F2710-L],
[F2810-L]
5p
[F2721/D-L],
[F2821/D-L]
C552
1.5p [Other]
4p
[F2710-H],
[F2810-H]
5p
[F2721/D-L],
[F2821/D-L]
C432
1.5p
[L]
only
C573
5p [H]
only
L39
1.5nH [H]
18nH [L]
C384
0.5p [H]
2p [L]
C258
1p
R195
270
R197
270
R196
22
C246
10p [H]
6p [L]p
C264
18p [H]
12p [L]
C516
10p [H]
6p [L]
R244
33
R422
470
L34
15nH
R383
100k
R182
10
C266
0.5p
C268
1.5p [H]
0.5p [L]
C348
2p
C203
15p
R100
100k
C132
390p
R470
47k
R483 330k
Q45
DTC144EU
R103
120k
R104
47k
R384
180k
R152
270
R133
150
Q46
2SC4116
Q50
2SK880
Q47
2SC4116
R176
680 [L]
330 [H]
R179
330
L53
7.5nH
[H] only
L12
10.5nH
[L] only
C196
5p
L54
7.5nH
[H] only
L14
10.5nH
[L] only
L51
0.82H
C224
9p [L]
12p [H]
C225
4p
C156
10
C555
10
FI4
FL-380
46.350 MHz
1
IN
2
OUT
3
GND
4
GND
5
6
IC29
RA30H4452M-21
[H-25W]
RA30H4047M-21
[L-25W]
RA55H4047M
[L-45W]
RA55H4452M
[H-45W]
1
RF INPUT
2
GA
TE BIAS
3
DRAIN BIAS
4
RF OUT
R154
330
C204
2p
C202
2p
C231
0.001
C219
10p [L]
15p [H]
C188
8P
C191
5p [L]
7p [H]
C265
2p
C349
2p[H]
3p[L]
R320
PRF18BC4710B1RB
[F2721/D], [F2821D]
only
D21
DAN222TL
R295
1.5k
RSSI
TMUT
T2
T2
RSSI
DET
SQL
RSSID
DFIL
NOIS
NWC
IF
T8V
T8V
R8V
R8V
R8V
APCV
APCV
R8V
T8V
T8V
T8V
R8V
8V
8V
HV
HV
FWD
REV
R259
47k
D7
HVC383
L15
1.2H
L47
1.2H
L52
1.2H [L]
0.82H [H]
L46
1.2H
L48
7.5nH
D13
HVC350
L9
1.2H
C192
6p [H]
7p [L]
C543
15p
C546
8p [H]
15p [L]
C194
0.5p
C127
1
C128
0.001
R98
82k
F
TL
V
A
MOD
C554
1.5p [H]
4p [L]
C544
12p [H], 39p [L]
R456
10
R126
12k [H],
18k [L]
R125
100k
R150
220k
C197
5p [H]
4p [L]
C193
0.1
C535
0.001
C536
0.001
D9
HVC383
D70
HVC350
D12
MA368
IC39
TA8225L
STBY
TJDET
NF2
IN+
PREGND
IN-
NF1
EMGDET
RIP
VCC1
OUT1
BS1
PW
-GND1
PW
-GND2
BS2
OUT2
VCC2
C468
220
C470
220
C443
100
C444
100
C471
100
R367
1
R368
1
R351
68
R353
68
R350
1k
R355
33k
C448
0.001
R328
10k
C446
0.1
C442
47p
C412
0.1
R349
220k
R354
220k
R325
2.2k
C414
0.01
C469
0.001
IC34
TA75S01F
1
2
3
4
5
R327
100k
R352
3.3k
R366
3.3k
C415
0.1
R326
100k
C413
470p
R424
100k
C445
47
C472
0.047
C473
0.047
R329
100k
SIGNAL
HLC
H_OUT2
H_GND
H_GND
C495
47p
C496
47p
C497
47p
C505
47p
C499
47p
C500
47p
C501
47p
C503
47p
C504
47p
C508
47p
C509
47p
C498
47p
J11
R414 1k
R406 1k
R409 1k
R411 1k
R407 4.7
R410
4.7
R413 1k
R405 1k
R415 1k
R416 1k
R417 1k
C511
47p
C513
47p
H_OUT2
CTS
RTS
RDAT
RXD
TXD
BUSY
H_OUT2
H_OUT1
H_OUT1
H_OUT1
CPU5
CPU5
MAIN CPU
IC23
HD64F2268TF
1
PM6/SEG31
2
PM5/SEG30
3
PM4/SEG29
4
PM3/SEG28
5
PM2/SEG27
6
PM1/SEG26
7
PM0/SEG25
8
PL7/SEG24
9
PL6/SEG23
10
PL5/SEG22
11
PL4/SEG21
12
CVCC
13
PL3/SEG20
14
VSS
15
PL2/SEG19
16
PL1/SEG18
17
PL0/SEG17
18
PK7/SEG16
19
PK6/SEG15
20
PK5/SEG14
21
PK4/SEG13
22
PK3/SEG12
23
PK2/SEG11
24
PK1/SEG10
25
PK0/SEG9
26
PJ7/WKP7/SEG8
27
PJ6/WKP6/SEG7
28
PJ5/WKP5/SEG6
29
PJ4/WKP4/SEG5
30
PJ3/WKP3/SEG4
31
PJ2/WKP2/SEG3
32
PJ1/WKP1/SEG2
33
PJ0/WKP0/SEG1
34
P10/TIOCA0
35
P11/TIOCB0
36
P12/TIOCC0/TCLKA
37
P13/TIOCD0/TCLKB
38
P14/TIOCA1/IRQ0
39
P15/TIOCB1/TCLKC
40
P16/TIOCA2/IRQ1
41
P17/TIOCB2/TCLKD
42
AV
S
S
43
P97/AN9/D
A1
44
P96/AN8/D
A0
45
P47/AN7
46
P46/AN6
47
P45/AN5
48
P44/AN4
49
P43/AN3
50
P42/AN2
51
P41/AN1
52
P40/AN0
53
VREF
54
AVCC
55
PH7/TONED/TMCI4
56
MD1
57
OSC2
58
OSC1
59
RES
60
NMI
61
STBY
62
VCC
63
XTAL
64
VSS
65
EXTAL
66
FWE
67
MD2
68
P77/TXD2
69
P76/RXD2
70
P75/TMO3/SCK2
71
P74/TMO2
72
P73/TMO1
73
P72/TMO0
74
P71/TMRI23/TMCI23
75
P70/TMRI01/TMCI01
76
P30/TXD0
77
P31/RXD0
78
P32/SCK0/SD
A1/IRQ4
79
P33/TXD1/SCL1
80
P34/RXD1/SD
A0
81
P35/SCK1/SCL0/IRQ5
82
PF3/ADTRG/IRQ3
83
C2
84
C1
85
V3
86
V2
87
V1
88
PH3/COM4
89
PH2/COM3
90
PH1/COM2
91
PH0/COM1
92
PN7/SEG40
93
PN6/SEG39
94
PN5/SEG38
95
PN4/SEG37
96
PN3/SEG36
97
PN2/SEG35
98
PN1/SEG34
99
PN0/SEG33
100
PM7/SEG32
R261
100k
C248
0.1
C249
0.1
C250
0.1
R285
1k
C308
0.1
R264
100k
X5
CR-764
19.6608 MHz
R187
12k
R189
12k
R190
12k
R188
10
D15
MA77
C232
0.1
C233
15p
C234
6p
C235
12p
R191
1M
R186
100k
R185
100k
D14 DAN222TL
Q15
DTA144EUA
R287
1k
R288
1k
R198
100
CP17
R387
100k
R286
100k
R393
100k
R392
47k
IC46
S-80942CNMC
1
OUT 2
VDD 3
VSS
4
NC
5
CD
C515
0.027
R442
100k
R460
100k
UNLK
CDEC
SDEC
BEEP
SENC
DDST
NOIS
OPT3
OPT2
OPT1
MMUT
RMUT
LV
IN
BA
TV
CSI
CSO
DDAC
DDSD
NWC
CPU5
5V
NWC
NWC
TMUT
TXC
PLST
DAST
DSDA
CCK
CENC0
CENC1
CENC2
XRTS
DUSE
CSFT
TEMP
CSFT
EPTT
PWR
PWON
POSW
PW
ON
ESCL
PMFM
ESD
A
ESDA
ESDA
ARXD
AT
X
D
AFON
SCK
DTPD
PGI2
HORN
MFDA
HLC
DASW
PGI3
RSSI
PGO1
PTT
O
BU
S
Y
PTTI
PGO2
MDIO
MSCK
PGI1
DIM
PA
PA
2
SSO
MTCK
NTXD
NRXD
MRDF
IGSW
FMDA
MDIR
MTDT
EXST
EXOE
CIRQ
XCTS
ARES
MD1
CCS
HANG
J10
IC26
HN58X24128FPI
1
A0
2
A1
3
A2
4
VSS
5
SDA
6
SCL
7
WP
8
VCC
R262
10k
R263
100k
C306
0.1
ESCL
ESCL
GND
GND
GND
CPU5
CPU5
CPU5
CPU5
CPU5
CPU5
GPS
C378
0.001
C379
47p
C380
22p
C381
47p
C390
0.001
C329
470p
C352
47p
C351
0.001p
C350
330
Q49
XP1214
Q51
2SK3019
1
2
3
4
5
D71
HVC383
OUT0
BL
V
A
R57
47k
R58
100k
C82
0.1
C72
0.001
1
2
3
4
5
6
OUT1
LVIN
8V
CPORF
FINRF
5V
REF
MIX
IF
B
NWC
A
CPU5
5V
VCC
AFO
VOLTAGE LINE
TX LINE
RX LINE
Explanatory notes
Power OFF 4.6 V
ON
0.0
V
13.6 V
5.1 V
7.9 V
5.1 V
4.9 V
4.9 V
W 1.1 V
N 1.0 V
7.0 V
TX 0 V
RX 4.9 V
TX 2.5 V
RX 1.6 V
TX 4.1 V
RX 0.2 V
TX 7.9 V
RX 0V
TX 0.0 V
RX 3.5 V
TX 0.0 V
RX 1.9 V
TX 6.9 V
RX 0.0 V
TX 0.0 V
RX 2.8 V
TX 0.0 V
RX 7.5 V
TX 3.0 V
RX 0.0 V
TX 2.3 V
RX 2.1 V
6.9 V
6.4 V
6.4 V
TX: 7.0 V
RX: 7.0 V
TX 3.4 V
RX 0.0 V
TX 0.8 V
RX 0.8 V
11 - 4