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73
SCHEMATIC DIAGRAM
NX-420
X57-837 6/8, X54-376 (C/3) 1/1
AN
AM
AL
AK
AJ
OPTDET
OPTDET
SPAF
EXTMICSW
50V
PTT/RXD
TXD0
AFSW
MICI
5VC
/T_R
+B2
+B2
50CS
50CS
PTT
.
C910
10u
.
C912
0.47u
.
C911
100p
C924
100p
.
C906
1u
25
.
C908
0.1u
.
C904
220p
.
C902
1u
DMG6968U
.
Q904
C919
100p
DMG6968U
.
Q906
R917
100
.
J 9 0 1
1
3
4
2
R918
680
XC6209B502P-G
.
IC900
1
2
3
NC
VSS
CE
4
VIN
5
VoUT
C921
100p
C915
100p
.
IC901
TA7368FG
1
2
3
4
5
NC1
VCC
NC2
VIN
RIPPLE
6
NF
7
PHASE
8
PRE-GND
9
PW-GND
10
PoUT
.
R913
270k
C917
100p
C923
47p
.
C909
1u
25
.
C905
1000p
.
R908
270
.
R 9 0 7
47k
.
R904
47k
.
C907
1u
.
C914
220u 6.3
.
R910
10k
.
J 9 0 0
1
3
11
10
2
R914
47k
.
R902
56k
.
R901
10k
C918
100p
R916
27k
.
C903
100p
R919
5.6k
.
R439
47k
2SC5383-T111
.
Q403
R452
470k
R446
470k
.
R442
1.5k
.
C448
1u
C468
4.7u
.
R438
82k
.
D410
HSC119
R455
47k
.
R440
47k
R453
1k
L900
.
L904
.
CN902
1
2
3
4
.
L901
C920
100p
.
F900
.
R905
100k
RXD
TXD
.
R909
6.8k
.
Q905
UPA672T-A
.
R911
47k
.
C456
100p
.
C465
100p
.
L902
.
L903
R906
2.2k
C916
47p
D900
D900,D901
1SS416
MCH3914(8)-H
Q402
C464
100p
C440
100p
R441
100k
L408
270n
L420
2.2n
D404
D404,D406
1SV325F
L414
270n
C474
100p
L412
33n
L405
270n
R435
0
R429
0
D409
1SV278F
2SC5636
Q405
D403
1SV323F
L411
33n
2SC5636
Q407
C462
5p
C454
0.5p
R450
0
R427
0
C443
470p
D408
1SV278F
L406
270n
L421
3.3n
L423
10n
C457
4p
C481
2p
C479
2p
L407
270n
C446
4700p
L413
2 7 0 n
D405
1SV325F
C467
0.5p
D406
HVC376B
C452
1p
L422
2.2n
C451
1.5p
R462
100
C450
6p
R456
100k
D407
HVC376B
C441
100p
C459
6p
MCH3914(8)-H
Q401
R458
100
C463
5p
C460
5p
L416
270n
L409
270n
C473
10p
R454
100
C469
0.5p
C475
4p
R436
100k
C482
15p
C478
100p
C458
3p
L410
220n
L424
10n
L417
270n
C449
7p
C442
470p
C483
1.5p
C455
0.5p
R449
100k
R459
100
C480
12p
R434
0
D402
1SV323F
C466
100p
C476
100p
L415
L906
FK330301
.
Q903
.
R920
100k
2SA1362-F(GR)
.
Q902
R470
0
R471
0
L418
2.7n
L419
15n
Q900
LTC014EEBFS8
.
Q901
LTC014EEBFS8
.
C461
10u
10
C470
100p
C472
100p
C477
100p
Q404
EM6M1
.
D901
DA3S103E
FJ330301
Q406
R447
22
R445
220
R444
220
R451
22
.
R912
330k
MICI
PTT/RXD
SPO
AE
OPTDET
SPI
50V
MICO
TXD
VCO_MOD
PTT
+B
50R
33A
THP
50T
TCXO(16.8MHz) Out
APC
50CS
50R
33A
THP
+B
50T
TCXO(16.8MHz) Out
APC
Fin
E X T
MIC
E X T
SP
I N T
SP
A
C91
470p
.
MIC1
T91-0673-05
MIC SECTION
(X54-3760-XX)(C/3)
VCO FREQ CONT
VCO FREQ CONT
VCO FREQ ASSIST
D405,D407
D408,D409
VCO FREQ ASSIST
TX MOD
SPEED UP
REVERSE
CURRENT
PREVENTION
AVR (50V)
AF POWER AMP
VCO(TX/RX)
VCO(TA)
RIPPLE FILTER
Q406 CONT
DOUBLER
DC SW(VCO)
BUFF AMP
DC SW
Q902 CONT
DC SW (AF AMP)
AF MUT CONT
AF MUT SW
LEVEL CONV
AF MUT SW
1A
R:0.53V
T:0.53V
R:3.6
8
V
T:3.6
8
V
R:4.21V
T:4.21V
R:1.1
8
V
T:1.1
8
V
R:0.73V
T:0.73V
R:4.43V
T:4.42V
R:4.22V
T:4.21V
R:4.95V
T:4.94V
R:4.0
8
V
T:4.0
8
V
R:1.24V
T:1.27V
R:7.50V
T:7.39V
R:3.29V
T:0V
R:7.49V
T:0.26V
R:0V
T:0V
T(TA):4.1
8
V
R:0V
T:4.00V
R:0V
T:1.57V
R:4.20V
T:4.20V
T(TA):0V
R:4.
8
9V
T:4.
88
V
5.00V
2.94V
TX-RX UNIT (X57-8370-10)
Summary of Contents for NX-420 K
Page 80: ...NX 420 ...