Troubleshooting Charts:
PA Failure
5-49
PA Failure – Page 1 (7/800 PA)
Yes
No
Yes
Yes
No
No
Yes
Yes
No
No
Yes
No
Yes
Yes
No
No
Yes
Yes
No
No
Yes
Yes
No
1
Is current less
than 350 mA?
Replace Q1001
Is current
approximately
500 mA?
Is current
greater than 2A?
Use a spectrum
analyzer and high-
impedance RF probe.
Measure RF_IN_2 at
C1001.
Is the frequency
correct?
Is the power
level about 3
dBm?
Is the power
appoximately 36
dBm?
See FGU
troubleshooting
charts.
Check U1110 and
see FGU
troubleshooting
charts.
Measure power at
C1022.
Replace U1002.
Measure power at
C1411, and calculte
harmonic filter loss.
Is the loss less
than 1 dB?
Repair any issues
with 1400 series parts
in the harmonic filter.
PA and harmonic
filter are functioning
properly.
Measure voltage at
pin 4 of U1001.
Is voltage
approximately 6
V?
Replace U1002 and
Q1001.
Measure TX current
at 7/800 test
frequencies.
Measure voltage at
pin 5 of U1001.
Is voltage
approximately 7
V?
Replace U1001.
Measure voltage at
pin 3 of Q1102.
Is voltage
approximately 0
V?
Replace Q1104.
Measure voltage at
pin 1 of Q1102.
Is voltage
greater than 1.5
V?
Replace Q1102.
Measure voltage at
pin 6 and 7 of U1119.
Are Pins 6 and
7, 5V and
2.775V
Replace U1119.
6
If power issue is not
resolved.
4
Summary of Contents for ASTRO APX 7000
Page 1: ......
Page 4: ...iv Document History Notes ...
Page 24: ...2 4 Radio Power DC Power Routing VOCON Board Notes ...
Page 98: ...3 74 Theory of Operation Global Positioning System GPS ...
Page 163: ...Troubleshooting Charts PA Failure 5 59 ...
Page 164: ...5 60 Troubleshooting Charts PA Failure ...
Page 276: ...7 58 Troubleshooting Tables List of Board and IC Signals Notes ...
Page 318: ...8 42 Schematics Boards Overlays and Parts Lists Transceiver RF Boards VHF 700 800 Notes ...
Page 380: ...8 104 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF1 700 800 MHz Notes ...
Page 432: ...8 156 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF1 VHF Notes ...
Page 458: ...8 182 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF1 UHF2 Notes ...
Page 498: ...8 222 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF2 700 800 MHz Notes ...
Page 546: ...8 270 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF2 VHF Notes ...
Page 606: ...8 330 Schematics Boards Overlays and Parts Lists VOCON Boards Notes ...
Page 638: ...Glossary 10 Glossary Notes ...
Page 643: ......