Motorola CP150TM User Manual
Page 58
June, 2005
6880309N62-C
6-16
VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals
Notes:
U480
Dual Opamp
1
Unit 1 output
2.48
2
Unit 1 (-) input
2.48
3
Unit 1 (+) input
2.46
4
Ground
GND
5
Unit 2 (+) input
0.28
6
Unit 2 (-) input
0.29
7
Unit 2 output
0
8
Vcc
4.96
U490
Audio Power Amp
1
Enable/shutdown
0.12
(Unsquelched)
2
Bias reference
3.26
(Unsquelched)
3
(+) input
3.26
(Unsquelched)
4
(-) input
3.27
(Unsquelched)
5
(-) output
3.25
(Unsquelched)
6
Vcc
7.48
(Unsquelched)
7
Ground
GND
8
(+) output
3.29
(Unsquelched)
U510
Dual Opamp
1
Unit 1 output
1.75
2
Unit 1 (-) input
1.56
3
Unit 1 (+) input
1.55
4
Ground
GND
5
Unit 2 (+) input
1.55
6
Unit 2 (-) input
1.56
7
Unit 2 output
1.38
8
Vcc
4.96
1. All voltages are measured with a high-impedance digital voltmeter and expressed in volts DC relative to ground (0 V).
2. Voltages are measured with a DC input voltage of 7.50 + .02 volts DC applied to the battery connector (J301).
3. All voltages are measured in the squelched receive mode, unless otherwise indicated.
4. Voltages are identical for VHF and UHF models unless otherwise indicated.
Table 6-4. Troubleshooting Table for Board and IC Signals (Continued)
IC Designator
Pin
Pin Function
DC Voltage
Comments (Condition)