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10 - 1
SECTION 10
BLOCK DIAGRAM
LPF
R1
BPF
CERAMI C
BUFF
X1:CR-834
7.9872MHz
ID C
RESET
SP1
PHOTO
COUPLE
LCD
EEPROM
AF
AM P
TX/RX
SW
APC
CTRL
21.25MHz
BP F
XTAL
NOISE
DET
TX MUT E
CTRL
CI-V
I/F
ANT
IF
AM P
R184
RFOUT
DET
RF
AM P
2ND LO
BUFF
FM
DET
PWR
CTRL
YGR
AMP
PW R
AMP
LPF
BUFF
NOISE
AM P
DI M
CTRL
BPF
DSC
DECODER
R8
REG
VCO
+5
REG
BUFF
ANT
SW
BPF
LPF
BPF
BUFF
BUFF
FIL
LOOP
R1
R135
MI C
MUT E
AF
MUT E
BUFF
H/ L
DSCDEC
WXDEC
SEND
RCV
RMUTE
TMUTE
DSCENC
TXDE T
BPF
DSCENC
BPF
KEY
BOARD
CPU
LOGIC UNIT
2ND
MI X
2ND IF
AM P
HVS
PLL
NMEA+
NMEA-
External GPS
HM-164B/SW/G
CLONE
I C1:TA31136FN
21.7MHz
FRONT UNIT
MAIN UNIT
FI1:
FI2:
Q2:3SK131 Q1:3SK131
Q4:KTC4080
FI3:LT450EW
IC 8
DEV ADJ.
VR UNIT
IC 1
DS1:SDT-DM2360
Q2:KTA1664
IC4:HN58X2464TI
IC5:S-80942CNMC
IC2:PC357N6 IC3:TC7S14FU
Q6,7:KTC4075x2
IC6:LA4425A
I C10A:
IC10B :
Q5:KTC4075
IC3:NJM2211M
Q13,14:2SC4226x2
Q26:KTC4080
D16,17:
Q19,20:KRC404
I C4:S-AV35A(I F)
D21,22 :
Q21:FMW1
D1,D2:
D3:KDS122
I C7B:TC7W66F U
PROTECT
CTRL
D25:DSA3A1
HVS T5
HV
REVERSE
CTRL
T5
5V
CONNECT
R5
Q31:KTA2015
R8
R5
Q22:KRC402
SQL UNIT
I C6A:NJM2904M
2nd LO
T C7W66F U
I C9:KIA7805API
EXT SP
I NT SP
L308CCBx2
D4:KDV214E
D5–7:
K DV214Ex3
NJM4558M NJM4558M
I C7A:
Q32:KRC404
Q34:KRC404
Q33:KTA2015
Q36:KTC4075
Q35:KTA1664
D13,14:HVC350Bx2
SHIFT
Q12:KRC404
D11,12:MA2S077X2
Q 15:2SC4215
Q 16:2SC4215
M A2S077X2
Q 17:2SC4226
HSM88ASR
Q23:KTA2015
X2:CR-804A
Q3,4:KTC4075x2
Q6:DTC114TU
D2:1SS355
D1:1SS355
I C6B:NJM2904M
TX:156.025–157.425MHz
RX:134.350–141.575MHz
VCO Frequency range
Frequency range
T X:156.025–157.425MHz
RX:156.050–163.275MHz
RX LINE
TX LINE
COMMON LINE
DATA BUS
PWR Adj
D 8:MA742
FL-399A
FL-368