Schematics, Board Overlays, and Parts Lists – VHF
: Transceiver (RF) Section
8-11
6871620L01-C
May 28, 2008
Figure 8-10. VHF Frequency Generation Unit (VCO) Circuit – 2 of 2
VSF
NU
NU
1
VSF_VCO
R318
68
VSF
Vctrl
330pF
R304
C310
R306
10K
820nH
220
160
L302
R313
C314
330pF
L308
D303
C304
27nH
330pF
C333
15pF
C303
15
18pF
R315
C307
1pF
VSF_VCO
D301
330
R319
R314
470
R301
150nH
L311
30
C351
C1722
1000pF
C309
VSF_VCO
R305
10K
TX_OUT
13
TX_SWITCH
4
1
S
R
E
F
F
U
B
_
C
C
V
8
1
CI
G
O
L
_
C
C
V
330pF
RX_IADJ
8
RX_OUT
7
RX_SWITCH
3
SUPER_FLTR
TRB_IN
19
16
TX_BASE
TX_EMITTER
15
1
TX_IADJ
10
COLL_RFIN
20
FLIP_IN
1
1
S
R
E
F
F
U
B
_
D
N
G
9
G
A
L
F
_
D
N
G
7
1
CI
G
O
L
_
D
N
G
12
PRESC_OUT
RX_BASE
5
6
RX_EMITTER
2
U302
VCOBIC
50U56
4
820nH
2.2pF
L301
0.1uF
C313
C321
18
R317
R303
L307
33
1.5pF
39nH
C308
R302
C317
2.2pF
VSF_VCO
33
18.29nH
L305
C330
330pF
R307
180
100nH
6
3
1
4
L310
Q310
2
5
1
820nH
L313
1pF
C320
PRESC
D302
5.6K
NC
VSF_VCO
VSF_VCO
R310
330pF
C322
820nH
L303
3.3pF
820nH
C305
NC
L312
18pF
C316
C306
1.8pF
330pF
C315
C301
12pF
470
R316
C302
15pF
C350
L304
47nH
L309
820nH
11.87nH
L306
AUX3
330pF
C318
PRESC
VCTRL
RXLO
TXRF
Summary of Contents for ASTRO XTSTM 4000
Page 1: ...COLOR CHORDS 7 ASTRO XTSTM 4000 Portable Radio Detailed Service Manual ...
Page 2: ......
Page 16: ...May 28 2008 6871620L01 C xiv Commercial Warranty Notes ...
Page 22: ...May 28 2008 6871620L01 C 1 6 Introduction Notes ...
Page 26: ...May 28 2008 6871620L01 C 2 4 Radio Power Notes ...
Page 56: ...May 28 2008 6871620L01 C 3 30 Theory of Operation Notes ...
Page 100: ...May 28 2008 6871620L01 C 6 8 Troubleshooting Waveforms Notes ...
Page 194: ...May 28 2008 6871620L01 C B 2 Motorola Service Centers Notes ...
Page 204: ...May 28 2008 6871620L01 C Glossary 10 Glossary Notes ...
Page 209: ......