Kenwood NX-820 Service Manual page 109

U
TX-RX UNIT (X57-8240-13)
B-BUS
.
D703,704
D703 AF Detector
DA3S101F
.
D704
DA3S101F
.
MIC SUM
R769
. 680k
.
C765
R778
27k
22p
.
C743
. 47p
R748
100k
DI
.
R741
47
.
C732
1000p
.
Noise AMP
Q702
KTC4075E(Y,GR)
RX SUM AMP/LPF(RX AF)
RX SUM
BU7462NUX
1
2
3
4
VSS
B-BUS
V
SCHEMATIC DIAGRAM / 原理图
.
Q 70 4
.
2SC4738(GR)F
R775
Q703,704
5.6k
MIC AGC
.
R777
.
10k
Q703
2SA1832(GR)F
.
Q706
.
SSM3J15FS Mute(MI2)
. . .
.
Q705
Mute(MI1)
C774 C782 C812
R787 SSM3J15FS
1 2k
0.1u 0.1u 10u 10
.
IC 7 03
BU 7 46 2 NU X
MIC SUM AMP/
LPF(DI)
.
. .
C784
R751 R756
100k
1k
10u
Reverse
Current Prevention
ASQ
CN701
.
.
D702
.
1SS422
R750
C741
39k
0.22u
Noise
Detector
.
R837
5.6k
.
.
.
IC711
C704
R703
56k
1u 10
.
R705
VDD
68k
8
.
- +
7
R710
+ -
6
56k
5
.
C777
RXAF SMF
0.1u
W
{ 1.44V
MM2 DC
.
. .
1.44V
Bias
C806
SPAF R823 R819
12k
2.2k
1u
.
. . .
C791
R816 C796 R820
PAAF
MI2
10u 10 12k 1u
2.2k
.
C790
.
1 0 u 10
R847
INAMT
22k
.
R 8 46
PA
.
22k
MM
Q709
SSM6N37FE
Q708,709
AF Mute Switch
DI
SDO0
SCK0
/EVCS
7
VoUT3
CN710
8 VoUT4
.
9 D/A Converter
VIN4
IC712
10 VIN5
R2A20178NP
11
VoUT5
12 VoUT6
33A_2
/IGN
X
NX-820
I C7 1 4
1.44V
.
1.44V
C797
0.22u
.
C798
0.22u R811
10k
2.7V
.
F7 0 1
.
2.5A
R813
1k
.
Q708
LTC014EEBFS8
.
C778
1u 10
.
C779 100p
VoUT2
24
VoUT1
23
VIN1
22
1 7
VIN8
21
.
DEO
VoUT8
20 R796
C788
VoUT7
19
4.7u
0
18
.
D 7 0 5
DI
EM Z6. 8 N
R79 7
0
19
D705,706
Line Protection
.
MIC/RX Selector(BINT)
I C7 1 3
TC 7W 53 FK(F)
5
A
GND
4
6
CH1
VEE
3
7
CH0
INH
2
8
VCC
CoMMoN
1
.
C786
0.1u
MIC RX SEL
X57-824 5/10
Y
B-BUS
}
DC
Bias
.
J701
SP2
20
DA TO
DATAI
D7 06
EM Z6 .8 N
/IGN
SP-
SP +
MIC
ME
B-BUS
109