3-8
TROUBLESHOOTING TABLES
U201
Freq Synthesizer
24
Ref osc XTAL2
0
25
Ref osc warp output
3.00
26
Superfilter cap
4.48
27
Superfilter base (NU)
3.76
28
Superfilter output
4.52
29
NC2
0
30
Superfilter input
4.96
31
NC3
0
32
Prescaler input
1.97
33
Prescaler ground
GND
34
Prescaler Vdd
2.99
35
Prescaler Vref (NU)
1.97
36
Digital Vdd
2.99
37
TEST1 (NU)
0.01
38
TEST2 (NU)
0
39
Bias 2
3.38 (typ)
(1.34V in TX mode)
40
Bias 1
1.50 (typ)
(3.20V in TX mode)
41
Modulation output
3.42 (typ)
(1.62V typ in TX mode)
42
CCOMP (NU)
0.05
43
Steering line IOUT
9.62 (typ)
Depends on frequency
44
PD ground
GND
45
Steering line IADAPT
9.62 (typ)
Depends on frequency
46
Adapt switch (NU)
0
47
Voltage from charge pump
12.8
48
AUX1 output (NU)
2.98
U251
VCO / Buffer
1
TX VCO current adjust
4.50
2
RX VCO current adjust
4.35
3
Superfiltered input
4.51
4
Collector RF in amp
4.35
5
RX VCO base
1.27
6
RX VCO emitter
0.48
7
RX switch output (NU)
0
8
RX buffered VCO output
3.36
9
GND_FLAG
GND
10
TX buffered VCO output
3.36
11
GND_BUFFERS
GND
IC Designator
Pin
Pin Function
DC Voltage
Comments (Condition)
Summary of Contents for CP 140
Page 1: ...Commercial Series CP140 CP160 CP180 Portable Radios Detailed Service Manual 6866550D20 O ...
Page 2: ...ii ...
Page 4: ...iv ...
Page 12: ...viii ...
Page 28: ...iv ...
Page 40: ...1 12 THEORY OF OPERATION ...
Page 48: ...2 8 TROUBLESHOOTING TABLES ...
Page 50: ...3 2 CONTROLLER KEYPAD SCHEMATICS ...
Page 58: ...3 10 Keypad Board Parts List 8466565A01 O ...
Page 62: ...iv ...
Page 66: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS ...
Page 90: ...3 16 TROUBLESHOOTING TABLES ...
Page 92: ...4 2 VHF PCB SCHEMATICS PARTS LISTS ...
Page 108: ...iv ...
Page 112: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS ...
Page 136: ...3 16 TROUBLESHOOTING TABLES ...
Page 138: ...4 2 UHF1 PCB SCHEMATICS PARTS LISTS ...
Page 154: ...iv ...
Page 158: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS ...
Page 182: ...3 16 TROUBLESHOOTING TABLES ...
Page 184: ...4 2 UHF2 PCB SCHEMATICS PARTS LISTS ...
Page 200: ...iv ...
Page 204: ...1 4 MODEL CHART AND TECHNICAL SPECIFICATIONS ...
Page 228: ...3 16 TROUBLESHOOTING TABLES ...