Motorola GP Series Service Manual page 295

800MHz PCB 8480641Z03 / Schematics
DATA_2_VCO
DATA
CLK_2_VCO
CLK
CSX_2_VCO
CSX
UNSWB+_2_VCO
UNSWB+
RESET_2_VCO
RESET
CHASSIS_CONTACTS
M300
0 dBm to RX_FE
C253
RX_LO
82pF
PRESC
C254
68pF
TX BUFFER
5 mA current draw
R250
270
C286
68pF
R274
120
R254
L252
47K
220nH
Q251
L250
R271
6.8nH
33
R251
100
C256
1pF C290
56pF
4.6 V Super Filter VSF
Supply from U201
R256
0
C255
R255
330
0.5pF
C259
C262
NU
2.2µF
0.1µF
L253
390nH
R275
10
C260
68pF
L254
33nH
18
VCC_LOGIC
8
RX_OUT
10
TX_OUT
12
PRESC_OUT
7
Rx_sw
RX_SWITCH
13
Tx_sw TX_SWITCH
Switched supplies for VCOs
on this page
17 11
5V when selected
AUX3_5V
C257
68pF
C284
L264
TX_INJ
15nH
56pF
R253
10
C283
0.5pF 6 dBm typical
L265
NU
to PA
47nH
LEVEL SHIFT FOR VCO SELECT
Allows 3V logic from frac-N to control 5V logic of VCO
RX VCO Components
R262
C274 C280
33
68pF 0.1µF
R273
33
L260
220nH
14
VCC_BUFFERS
C288
3 NU
SUPER_FLTR
0.5pF
1
TX_IADJ
2
RX_IADJ
4
COLL_RFIN
U250
5
C258
RX_BASE
6
0.1µF
RX_EMITTER
16
TX_BASE
15
TX_EMITTER
20
FLIP_IN
19
TRB_IN
9
VCO Select Line
R257
0V for RX
5V for TX
1K
C263
R261
C287
68pF 33
100pF
Q252
4 3
2
L256
AUX4
220nH
1
R263
270
TX VCO Components
Freq Range
741 to 761 MHz
L259
R264
U205
220nH
270
C267
900 MHz
2pF
C278
C266
3.9pF
2pF
C273
C279
0.5pF
3.3pF
NU
L258
CR252
220nH
C275
1.2pF
1.9 V when selected
R270
33
R267
CR253
Rx_sw
12K
R265
30K
R269
C269
0
NU
.033µF
DACRX
OPTIONAL BIAS TUNING VOLTAGE
1.9 V when selected
C270
0.1µF
L257
R272
220nH
33
C285 R266
C289
0.1µF 30K
.033µF
R268
22K
C276
C271
L261
22nH
C272 3pF
5.6pF
CR251
0.5pF
C265 NU
1.8pF
C277
U206
5.6pF
1.225 GHz
C268
1pF
Freq Range
806 to 870 MHz
800MHz (806-870MHz) Voltage Controlled Oscillator
4-9
L263
18nH
VCTRL
L262
220nH
C282
68pF
Steering Line
2 to 11 VDC
Tx_sw
C281
C291
68pF
0.5pF
NU
ZMY0130988-O
SH251 SH250
1 1
VCO TOP SHIELD VCO BOTTOM SHIELD