1-158 (No.RA053<Rev.001>)
5.4
Failure diagnosis of the VCO section (NX-3220)
[Overview]
The VCO circuit is mounted inside the BLS. BLS stands for "Board Level Shield".
This BLS has no lid and provides high shielding performance. Because BLS is difficult to solder, components inside the BLS can't be
soldered.
When there is a problem with the VCO circuit, the VCO can't be repaired.
If the VCO function doesn't work, use this flow chart to identify the problem.
The following is explained about failure diagnosis of VCO circuit inside a BLS<E101>.
[About a BLS]
BLS is shielding case
BLS for VCO area is integrated type and can not be removed
[Prediction problem related to the VCO circuit]
• PLL Unlock
<Radio state>
- Unlock beep
- VCO Assist voltage tuning is impossible
<The cause>
- VCO control voltage is abnormal
- VCO Assist voltage is abnormal
- VCO power supply is abnormal
- VCO signal output circuit is abnormal
[VCO circuit inside a BLS<E101>]
VCO_MOD
ASSIST
CV
ASTSW
/SA
V
E
CPZ
50C
50C
R122
6.8k
$D101
$C101
$ Q 1 0 1
$R101
R 1 0 2
0
C 1 0 3
3 3 p
C102
0.01u
D1
1
1
1SS400SM
R103
22k
I C 1 0 2
B U 7 2 9 5 H F V
1 IN+
2 VSS
3 IN-
4
oUT
5
VDD
C 1 9 8
2 . 5 p
(B)
C192
12p
(G)
L 1 9 2
2 7 n
(H0AM)
C191
6p
(B)
C107
100p
C 1 9 3
2 . 5 p
(B)
C194
6p
(B)
L 1 9 1
2 7 n
(H0AM)
C 1 0 4
1 0 0 p
C 1 0 6
0 . 1 u
R109
47
R1
1
3
47k
C 1 9 7
4 7 0 p
C N 1 9 1
R125
0
R1
1
1
4.7k
C1
1
2
4.7u
10
2 S D 2 6 5 4 / W /
Q 11 3
D102
EDZV8.2B
I C 1 0 1
O PA 1 7 0 A I D R L R
1 IN+
2 V-
3 IN-
4
oUT
5
V+
Q 1 0 2
E M 6 M 2
R 1 0 6
1 0
R181
22
R 11 2
1 k
C1
1
1
470p
R129
10k
R121
10k
C N 1 0 1
R104
1k
C 1 0 5 1 u
50
2 S C 5 1 0 8 F T / Y /
Q 1 8 1
R182
8.2k
R183
4.7k
C181
470p
R184
150
L181
5
6n
LK73H0AM56NJ
R1
1
0
100k
C182
470p
R107
100k
C 1 8 3
4 p
(B)
R 1 0 8
1 0 M
E 1 0 1
F 1 B - 0 0 9 5 - 0 0
R 1 0 5
1 2 0 k
C 1 4 6
6 p
R136
10k
L143
47n
LK73H0AM47NJ
R131
100k
C139
8p
(B)
2 S C 5 1 0 8 F T / Y /
Q 1 5 1
L135
270n
L41-2785-53
L140
270n
L41-2785-53
L132
270n
L41-2785-53
L137
270n
L41-2785-53
L 1 3 9
2 7 0 n
L41-2785-53
C140
7
p
L142
270n
L41-2785-53
C 1 4 1
9 p
C137
3p
C123
0.047u
C138
0.75p
C121
0.15u
CK73FBB1H154K
C 1 4 4
0 . 5 p
R130
150
$C131
R 1 2 6
0
R145
180
R 1 2 7
0
C145
470p
C132
470p
L 1 3 6
LB73H0AY-00 4
R 1 2 8
3 9 0
(D)
C135
470p
L 1 2 1
LB73H0AY-00 4
C 1 3 4
1 0 0 0 p
R133
150
RN(D)
R 1 3 4
1 0
RN(D)
L141
LB73H0A
Y
-00
4
C 1 3 3
1 0 0 0 p
R 1 3 5
0
C147
470p
C142
470p
L 1 3 1
2 7 0 n
L41-2785-53
R 1 3 2
0
$C143
R142
150
C122
10u
2
0
CS77ABE1D100M
MCH3914-H/8/
Q 1 3 1
D136
SMV1
130-079L
F
D 1 3 5
SMV1801-079LF
D133
SMV1801-079LF
D132
D 1 3 4
SMV1801-079LF
D131
SMV1251-079LF
R143
5.6k
R120
470k
R 1 2 4
4 7 k
R123
470k
Q 11 4
V T 6 M 1
L 11 2
LB73H0AY-00 4
Q103
VT6M1
R 1 4 1
4 7 0 k
R 1 4 0
4 7 0 k
L 1 3 8
33n
L41-3378-08
C108
0.1u
R137
0
R1
1
6
0
R 1 3 9
0
R 1 9 5
0
R 1 9 4
3 3
$R191
R193
180
ASSIST
CV amp
4.3V
4.1V
3.2V
VCO
VCO Buffer
BLS
VCO circuit inside a BLS (in a dotted line)
[A]
This point is inside other BLS<E301>
[C]
[D]
[E]
[F]
[G]
[H]
[ I ]
[B]