Motorola CP150TM User Manual
Page 50
June, 2005
6880309N62-C
6-8
VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals
U110
RF Power Amp
1
RF input
0
(TX mode)
2
Vgg (gate bias)
2.65 (typ)
(TX mode) (4.25 V typ at VHF)
3
Vdd
6.59
(TX mode)
4
RF output
--
Do not measure
5
Ground
GND
U150
Dual Opamp
1
Unit 1 output
4.20 (typ)
(TX mode) (5.8 V typ at VHF)
2
Unit 1 (-) input
2.39 (typ)
(TX mode)
3
Unit 1 (+) input
2.39 (typ)
(TX mode)
4
Ground
GND
5
Unit 2 (+) input
3.30 (typ)
(TX mode)
6
Unit 2 (-) input
3.35 (typ)
(TX mode)
7
Unit 2 output
2.23 (typ)
(TX mode)
8
Vcc
6.79
(TX mode)
U201
Freq Synthesizer
1
AUX2 output (NU)
0
2
AUX3 output (TRB)
0.03
To U251-19 (RX mode)
3
AUX4 output (NU)
0
4
Lock detect output
2.98
To U401-56
5
PD Vdd
2.98
6
Digital ground
GND
7
Serial data input
3.23
8
Serial clock input
0
9
Synth chip select
3.23
From U401-47
10
Modulation input
1.50
From U451-40
11
VMULT4 (NU)
2.98
12
VMULT3 (NU)
0
13
VRO
4.96
14
VMULT2
1.49
15
VMULT1
1.49
16
INDMULT (NU)
0
17
NC1
0
18
Ref select (NU)
0
19
Buffered 16.8 MHz out
1.54
20
Analog Vdd
3.00
21
V bypass (NU)
1.55
22
Analog ground
GND
23
Ref osc XTAL1
2.07
Table 6-4. Troubleshooting Table for Board and IC Signals (Continued)
IC Designator
Pin
Pin Function
DC Voltage
Comments (Condition)