Motorola CP160 - Page 191

UHF2 PCB 8486348Z13-C Schematic Diagrams 4-9
PRESC_OUT
TX: 3V
UHF R2 VCO
3.2V to 9.5V
4.5V
RX: 0V
15nH
L281
L292
15nH
L282
27nH
910
R282
NC
VCO_MOD
VCO_VSF
150
R283
C267
1.3%
7.5pF
0.1uF
C272
330
R284
L276
27nH
R277
0
R276
1K
VCO_3V
C251
150pF
8.2K
R281
220nH
L272
6.8nH
L291
V_SF
R254
100
C276
VCO_PRESC
6.8pF
3.3pF
C290
C282
C291
18pF
6.8pF
390pF
NU
C271
5.6K
L271
1
R272
C274
SHIELD
SH253
SHIELD
SH250
1
0.1uF
27nH
L262
0.5pF
C268
V_SF
VCO_RX_INJ
R253
33
R280
4.7K
NU
3.9pF
2.5%
C256
C252
R274
33
C253
27nH
L252
R262
6.2pF
1.6%
6.8K
C284
390pF
D261
2pF
5%
C264
4.7pF
2.1%
C263
100
R275
R273
330
1
3
2
0
R285
Q280
BFS540
VCO_TRB
D251
VCO_V_STEER
R271
5.1K
C281
C285
390pF
390pF
0.1uF
C292
12.5nH
2%
L254
VCO_TX_INJ
6.2pF
C286
C275
390pF
C283
390pF
V_SF
D262
1SV229
NC
L255
220nH
22K
R261
TX_EMITTER
1
TX_IADJ
10
TX_OUT
13
TX_SWITCH
14
VCC_BUFFERS
18
VCC_LOGIC
RX_BASE
6
RX_EMITTER
2
RX_IADJ
8
RX_OUT
7
RX_SWITCH
3
SUPER_FLTR
TRB_IN
19
16
TX_BASE
15
4
COLL_RFIN
20
FLIP_IN
11
GND_BUFFERS
9
GND_FLAG
GND_LOGIC
17
12
5
L251
U251
50U54
VCO_5R
220nH
L283
.01uF
C273
NU
C254
C255
5.1pF
2%
33
5.6pF
0.1%
C257
R263
SHIELD
SH251
1
1%
12pF
2.4pF
0.1%
C270
390pF
L265
220nH
C266
220nH
100
L270
12.5nH
2%
L264
R264
C265
TX_INJ
3.3pF
3.0%
5R
VCO_MOD
PRESC
V_STEE R
RX_INJ
V_S F
3V
TR B
UHF2 (438-470 MHz) Voltage Controlled Oscillator Schematic