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67
SCHEMATIC DIAGRAM
NX-420
X54-376 (A/3) 2/2, X54-376 (B/3) 1/1
J
I
H
G
F
D
C
-t
SDO0
SCK0
/EVCS
MOD
MIC
DISP_VER
MICI
SPAF
TV1
TV2
ASQ
TV2
TV1
MICI
SPAF
MIC
ASQAPC
SDO0
SDI0
SCK0
ASQAPC
ASQ
/LCDCS
/EVCS
MOD
50C
RXAF_2
SQ_SW
VCO_MOD
VREF
VREF
33A
33A
33A
33A
33M
SB2
.
L1
✽
R86
✽
R84
.
L2
R34
100k
R50
22k
R35
100k
C74
1u
R45
100k
R44
100k
C49
1000p
C70
1u
C54
330p
R33
100k
C58
68p
C45
R53
1.8k
IC6
TC75W51FK(F)
1
2
3
4
oUTA
VSS
5
6
7
oUTB
8
VDD
C48
1u
C67
1000p
C68
0.01u
R30
0
C23
C34
47p
C7
R52
470
C26
47p
C31
47p
C28
47p
C29
C33
C42
C44
47p
C43
.
S2
S70-0516-05
.
S3
S70-0516-05
.
S4
S70-0516-05
CP1
100x4
C N 6
1
2
3
4
5
6
R23
0
R24
0
C35
0.1u
R29
0
R28
0
C47
0.1u
C40
47p
C36
47p
IC4
R2A20178NP
1
VIN2
2
VDD
3
LD
4
CLK
5
DI
6
VIN3
7
VoUT3
8
VoUT4
9
VIN4
10
VIN5
11
VoUT5
12
VoUT6
13
VIN6
14
VDAREF1
15
VDAREF2
16
RESET
17
GND
18
VIN7
19
VoUT7
20
VoUT8
21
VIN8
22
VIN1
23
VoUT1
24
VoUT2
R18
39k
C16
1000p
C13
100p
TH1
C19
0.1u
C21
0.01u
IC1
TC75W51FK(F)
ASQ BPF
1
2
3
4
oUTA
IN-A
IN+A
VSS
5
IN+B
6
IN-B
7
oUTB
8
VDD
R17
100k
R19
220k
R9
33k
C22
0.22u
R4
82k
R2
10k
R15
3.3k
C25
C5
0.1u
C10
100p
C20
1000p
R14
330k
D2
KDR731
R8
15k
C2
680p
KTC4075E(Y,GR)
Q3
R11
330k
R13
470
C3
27p
C6
1000p
R20
220k
C8
.
S1
S70-0516-05
C11
680p
SSM3K15TE(F)
Q2
R12
330k
C30
1u
R21
56k
C32
1200p
R22
56k
C38
180p
R26
68k
R16
47
R10
0
IC2
TC75W51FK(F)
1
2
3
4
oUTA
IN-A
IN+A
VSS
5
IN+B
6
IN-B
7
oUTB
8
VDD
C39
0.1u
CN5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
R37
150k
C62
100p
C71
0.1u
R47
22k
R78
6.8k
R77
10k
R79
56k
C92
1000p
R81
0
C73
10u
✽
R82
R88
0
C52
0.1u
2SC4738(GR)F
Q4
R40
10k
D3
DA221
R41
68k
C53
0.1u
D4
DA221
R39
10k
C63
1u
C64
1u
R42
68k
2SA1832(GR)F
Q5
PTT
Side 2
Side 1
GND
+
-
+
-
PTT
/S1
/S2
/EMG
GND
AUX
(0V-1.65V)
(0V-3.3V)
X54-3760-XX
-10
NO
-12
3.3k
47p
47p
47p
47p
47p
47p
47p
0.22u
1000p
SB2
LEDG
LEDR
33M
33A
33M
D/A CONV
AGC DET
D3,4
MIC AGC
Q4,5
VCO MOD/VREF
AF LPF/MIC AMP
SQL NOISE AMP
BW SW
NOISE DET
50C
50C
50C
33A
C15
0.01u
C37
4700p
PTT SECTION
(X54-3760-XX)
(B/3)
TX-RX
UNIT(X57-8370-XX)
CN604
TX-RX UNIT (X57-8370-XX) CN600
1
NO
R84
R86
0
0
NO
R82
100k
K3
K
DISP_VER
5.00V
R:7.47V
T:7.25V
3.30V
3.30V
DISPLAY UNIT (X54-3760-XX) (A/3)
Summary of Contents for NX-420 K
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