Icom IC-M21 Service Manual - page 29
10 - 1
SECTION 10
BLOCK DIAGRAM
ANT
LPF
D52, D90: 1SV307
D91: 1SS375
D80: 1SS375
C87: 2 P
Q51: 2SC4081 R
Q52: XP6401
Q54: 2SK2974
Q53: 2SK2973
PWR
DET
ANT
SW
PWR
AMP
HV
I.SENS
APC
CTRL
IC50: NJM2125F
PRE
DRIVE
BUFF
Q50: 2SC4226 R25
BPF
TX/RX
SW
D50, D51: MA77
PCON
BPF
D92: MA77
D93: MA728
Q90: 2SC4226 R25
D130: MA77
Q150: 3SK272
BPF
RF
AMP
BPF
FI150, FI151
(21.7 MHz)
IF
AMP
Q151: 2SC2714 Y
IF
BUFF
BUFF
BUFF
Q24: 2SC4215 O
Q25: 2SC4215 O
R5V
Q23: 2SC4215 O
Q21, Q22: 2SC4226 R25
D22, D23: HVU350B
MOD
MUTE
Q20: DTC144EUA
D20: MA2S077
D21: MA77
VCO
VCO
LOOP
FIL
PLL IC
IC1: UPD3140GS
IF DET IC
IC170: TA31136FN
21.25 MHz
2nd LO
DET
BPF
FI170
(450 kHz)
X170:
CDBCB450KCAY24
(450 kHz)
D/A
IC190: M62363FP-650C
MODC
LPF
LIMIT
AMP
IC200D: NJM2902V
IC200A: NJM2902V
IC260: TC4W66F
ANALOG
SW
LPF
IC200C: NJM2902V
BEPO
AF MUTE
SW
DE-
ENPHA
MIC
AMP
IC200B: NJM2902V
R286: 10 k
C285: 0.1
AFVS
Q280: 2SC4213 B
IVOLM
AF
AMP
AF
REG
PRE
ENPHA
R253: 2.2 k
C254: 0.01
Q230: 2SB1132 Q
Q231: XP6501 AB
HV
IC280: TA7368F
PTT
CONT
Q250: UN911H
PTT
GND
MIC
CLONE
AFOUT
SPO
J250
EXP JACK
MIC
PTT
SP
VCC
HV
POWER
VCC
VR
VR
VOLO
GND
VOLIN
GND
BTYPE
REF
X1: CR-726
D1: HVU17
(21.25 MHz)
FCON
L
C
D
IC360: HD6433844RA60H (FX-2497A)
IC220: NJM2870F05
VCC
CPU
SV
DS360: A0153A
X360: CR-610
(7.9872 MHz)
DS240–DS245
CPU
LED
LED SW
Q240: XP1213
KEY
EEPROM
IC340: HN58X2416TI
CPU5V
IC341: S-80942ANMP-DD6
RESET
R300–R315
ATIS1–8
D/A
VCC
T5V
V5V
R5V
5V
REG
V5
REG
R5
REG
SV
REG
T5
Q223: DTC144EUA
Q224: XP6501 AB
Q225: 2SB1132 Q
5VS
T5VS
R5VS
V5VS
ATIS
BTYPE
BEEP
CLOUT/CLIN
PTT
WXTV
BUFF
Q350: DTC144TU
D350: DA204U
RSSIV
NOISV
Q221: 2SA1588 GR
Q220: 2SA1588 GR
Q222: 2SA1588 GR
UNLK
VOLO
MICM
DETM
SQLO
SQLI
TDETV
1st LO
,
,
,,,,,,
,,,,,,
,,,,,,
,,,,,,
,,,,,,
,,,,,,
,,,,,,
,
,
,,
,,,,,,,,
,,,,,,,,
,,,,,,,,
COMMON LINE
TX LINE
RX LINE
T5V