Kenwood NX-900 Service Manual page 90

AE
NX-900
2
13
2
ASQ DET
BPF/BUFFER
AMP (SQ)
ASQ BPF
R707
15k C716
220p
C718
220p
Q701
SSM3K15TE(F)
SQL SWITCH
(W/N)
SQ VOLTAGE
CONTROL
D702
R755
10k
HSC119
NOISE
R843
DETECTOR (SQ)
470
R : 2.25V
C740
4700p
C734
0.01u
Q702
R : 0.20V
2SC5383-T111
NOISE
AMP
VREF
IC703
TC75W51FK(F)
1
2
R703 R712
3
4
10k 68k
VSS
APC SMF
LPF
(APC/DEO)
1.67V
C717 0.1u
TC75S51FE(F)
RXAF SMF
1 IN+
C708
1200p
2
VSS
R713
3
IN-
56k
LPF (RXAF)
R708
68k
1
10
9
MI2
MI1
ME
90
X57-806 (A/2) 7/14
AF
SCHEMATIC DIAGRAM
13
2
33A_ 2
R729
100k
C722
47p
R727
1.67V
270k
D703
ASQ
R760
RB706F-40
1.5k
33A_2
8
VDD
7
R737 R744 C735
47k 47k 4.7u
6
5
1.67V
DEO BUFF
VREF
33A_2
IC701
5
VDD
4
oUT
SCSW(RXAF)
IC707
TC7W53FK(F)
R738
1k
5 4
A GND
6 3
CH1 VEE
7 2
CH0 INH
8 1
VCC CoMMoN
RXAF/RXEI SWITCH
1
10
9
AG
7
VoUT3
8
VoUT4
9
VIN4
10
R2A20178NP
VIN5
11
VoUT5
12
VoUT6
R836
0
1
R698 100k
1
C652 47p
IC720
TC75S51FE(F)
C781
1u 4 oUT IN-
DI
VSS
33A_ 2
5
VDD
IN+
DI SMF
1.67V
VREF
33A-2
TC75W51FK(F)
1
VREF
1.67V
2
R923
47k
3
MOD_REF
4
1
10
C745 R764
0.01u 120k
C749
0.1u
R756 R758 C747 R771
15k 10k 0.01u 100k
10
Q703
TONE
SSM3K15TE(F)
SWITCH
R769
4.7k
1
1
AH
TX-RX UNIT (X57-8060-10) (A/2)
2
33A_ 2
R833 100
R834 100
R835 100
2
24
VCO_MOD
VoUT2
23
IC719
VoUT1
22
VIN1
21
VIN8
20
VoUT8
19
VoUT7 MP
D/A
CONVERTER
1
R700 R723 R849
100k 1k 0
3
2
1
VREF
IC711
8
RX SUM
VDD
7
1.67V
6
5
VSS
SUM AMP
(AF) / VREF
R790
220k
33A_2
6
IC710
TC7W53FK(F)
R776
330k 1 8
CoMMoN VCC
2 7
C752 R777
INH CH0
0.01u 150k
3 6
VEE CH1
4 5
C753 R778
GND A
0.01u 390k
AF SWITCH
(AI TONE OPT9/VREF)
SIDE TONE MUTE
R782 R785 C775 R791
15k 10k 0.1u 560k
1
AI
13
SDO0 /INAMT
SCK0
/EVCS
1
2
2
2
VREF
1.67V
2
2
1
2
9
MI2
1 2
MI1
ME