Kenwood NX-300 Service Manual page 153

BD
TX-RX UNIT (X57-7370-11) (A/2)
THP
1
/T R
50C
IC500
TEMPERATURE SENSOR
+B
LM73CIMKX-0
4
I2CCK SMBCLK
5
ALERT
6
I2CSDA SMBDAT
VC
GND
33C
TCXO MOD
AF AMP for
TCXO MOD
R570 0
50T
2
50R
R527
0
50IF
D501,Q503
RIPPLE FILTER DC AMP for VCO TUNE
R : 14.34V R : 13.73V
T : 14.43V T : 13.82V
Q503
2SC5383-T111
150C
1
2
3
R : 14.33V
T : 14.41V
C563
100p
3
4
BE
SCHEMATIC DIAGRAM /
IC500
R572
3
VDD
2
10
GND
1
ADDR
R503
10
VCC
L500
oUTPUT
4.7u
X500
19.2MHz
R935 R573
15k 120k
IC501
TLV2381ID8V
1 OUT 5
VDD
2
GND R504 C511
100k 10u
3 4
IN+ IN-
C503
0.1u
BUFFER AMP
CN500
CV
L508
Q504
2SK879-F (Y)
220n
R537
1k
L503
R532 R538
0 390
L509
R576
220n
0
BYPASS
DIODE
D505
DA221
IC503
TLV2381ID8V
OUT 5
VDD
R539
GND
10M
R566
4
IN+ IN-
470k
BF
C515
R955
0.01u
0
R586
0
13
R956
LD/PS2
0 L599
14
VCC cp2
15
R957
CPout2
0
16
/Fvco
17
R958
Fvco
18
VCCcp2
0
L598
R511 10
SDO1
R512 10
/PCS_RF
R513 10
SCK1
PLD
R : 4.15V
T : 18mV
D506,510,514,515
FREQUENCY CONTROL
RX VCO
D510 L521
C556 R575 C566
470p 0 82p 27n
1SV290B-F
R : 2.5mV
T : 4.2V
TX VCO
L520
D511 22n
C557 C565
470p 1SV282-F 33p
D507,511,516,517
D519
R : 4.27V
FREQUENCY CONTROL
TX
T : 4.28V
MODULATION
C562 R552
1u 100k
OP AMP
R : 4.978V
(VCO MOD/APC)
R : 1.4V
T : 5.06V
T : 4.38V
IC504
Q507
TC75W51FUF
2SC5383-T111
1 8
VDD
7
2
3 6 R670
4 5
220k RIPPLE
VSS
FILTER
C600
0.1u
APC
BG
NX-300
原理图
C543
4p
L504
C525 C553 R577
12n
47p 10p 0
R583
0
C514
IC502
0.01u
SKY72300-362
PLL IC
6
CPout1
R522
5
VCCcp1
10
4
LD/PS1
C521 C526
3
/Fin
2 100p 0.1u
Fin
C527
1 R519
VCC
100p
10
C522
0.1u
C523
100p
C517 100p
C518 100p
C519 100p
L522
R560
Q512
220n
22
C573
BUFFER AMP
6p
C581
0.5p
R : 0.97V
R : 0.96V
T : 18mV
T : 0.43V
R : 4V
Q508
T : 4.03V
2SK508NV(K52)
R564
VCO
OSCILLATION
150k
L527
L524
220n
C576
2SC5636
5p
C583
0.5p
R : 2.5mV
T : 0.87V
Q509
2SK508NV(K52)
VCO
OSCILLATION
2SJ347F
Q510
SSM6L05FU-F
R : 4.26V
T : 6.94mV
R558
470k
Q510,511
T/R
SWITCH
R568
R : 3.25V
470k
T : 9.7mV
R : 0.15mV
T : 1.84mV
RIPPLE FILTER
R : 0.14mV
T : 4.08V
X57-737 (A/2) 2/4
BH
THP
50T
TX
R550 C588
0 10p
50C
+B
33C
3
19.2M
Q512
R : 1mV
T : 4.17V
Q511
3
50R
50IF
4
150C
153