Icom IC-M304 Service Manual page 25

SECTION 10 BLOCK DIAGRAM
FRONT UNIT
HM-164B/SW/G
SP1
I NT SP
VR UNIT
R1
SQL UNIT
R1
LOGIC UNIT
DS1:SDT-DM2360 KEY
BOARD
LCD
X1:CR-834
Q2:KTA1664
Q3,4:KTC4075x2
7.9872MHz
DI M
CTRL
IC5:S-80942CNMC
IC 1
CPU
RESET
Q6:DTC114TU
D3:KDS122
IC4:HN58X2464TI
CI-V
CLONE
I/F
EEPROM
IC2:PC357N6 IC3:TC7S14FU
D1:1SS355 D2:1SS355
NMEA+
PHOTO
BUFF
NMEA- COUPLE
I C6A:NJM2904M
BUFF
I C6B:NJM2904M
BUFF
BPF
DSCENC
10 - 1
EXT SP
Q5:KTC4075
WXDEC
LPF
IC6:LA4425A IC3:NJM2211M
AF DSCDEC DSC
AM P DECODER
I C7B:TC7W66F U Q6,7:KTC4075x2
AF
BPF
MUT E
RMUTE
DSCENC
I C7A: I C10A:
T C7W66F U NJM4558M
MI C
ID C
MUT E
D25:DSA3A1
REVERSE
HV
CONNECT
PROTECT
SEND
Q31:KTA2015
I C9:KIA7805API
Q32:KRC404
HVS +5 5V T5 T5
REG
CTRL
Q33:KTA2015
Q34:KRC404
R5 R5
CTRL
RCV
Q35:KTA1664
Q36:KTC4075
R8 R8
REG
FI3:LT450EW
CERAMI C
BPF
I C1:TA31136FN
Q4:KTC4080 FI1:
D 8:MA742 FI2:
FM 2ND IF 2ND IF
DET AM P MI X AM P
21.7MHz
NOISE 2ND LO
NOISE
AM P DET BUFF
X2:CR-804A
2nd LO
21.25MHz
IC 8 Q26:KTC4080
PLL
BUFF
Q13,14:2SC4226x2
D13,14:HVC350Bx2 Q 15:2SC4215
LOOP
VCO BUFF
FIL
IC10B :
NJM4558M
LPF
VCO Frequency range
SHIFT
TX:156.025–157.425MHz
DEV ADJ.
Q12:KRC404
RX:134.350–141.575MHz
D11,12:MA2S077X2
MAIN UNIT
Frequency range
T X:156.025–157.425MHz
RX:156.050–163.275MHz
FL-368 D1,D2:
FL-399A Q2:3SK131 Q1:3SK131 L308CCBx2
XTAL RF
BPF BPF
BP F AM P
D5–7: D4:KDV214E
K DV214Ex3
D16,17:
M A2S077X2 Q 17:2SC4226 I C4:S-AV35A(I F)
TX/RX YGR PW R
SW AMP AMP
HVS
Q 16:2SC4215
BUFF
RX LINE
TX LINE
COMMON LINE
DATA BUS
ANT
ANT
LPF
SW
D21,22 :
HSM88ASR
RFOUT TXDE T
DET
PWR Adj
Q21:FMW1
Q23:KTA2015 Q22:KRC402
APC PWR H/ L
CTRL CTRL
Q19,20:KRC404
TX MUT E
TMUTE
CTRL