1-52
Troubleshooting
Troubleshooting Assembly–Level Problems
1200 Power Supply
1. Press
View Details, highlight Self Test 1200, then press View Details again.
2. From the displayed self–test results, determine which supply or supplies failed.
3. Refer to the following table; disconnect one microcircuit at a time and run self–test 1200.
• If the test passes after disconnecting one or more microcircuits, replace the microcircuit.
• If self–test still fails after disconnecting all the microcircuits, replace the A26 MID.
1201 Mod Filter
1. Disconnect the cable between the A23 Lowband Coupler/Detector and the A30 Modulation Filter,
and connect a spectrum analyzer to the cable.
2. Tune the source across the lowband frequencies (250 kHz to 3.2 GHz) and record the lowest
power level.
3. Disconnect the cable coming from the A29 20 GHz Doubler, and connect the spectrum analyzer
to this cable.
4. Tune the source across the A29 20 GHz Doubler band of frequencies (3.2 GHz to 20 GHz) and
record the lowest power level.
5. Compare the levels recorded to the levels shown on the RF Path Block Diagrams on page 1-109.
• If the power level in both paths is good, replace the A30 Modulation Filter.
• If the power level in either path is bad, troubleshoot that path.
• If the power level in both paths is bad, check the signal levels out of the A28 YIG Oscillator.
1202 A29 20 GHz Doubler
1. Disconnect the cable between the A28 YIG Oscillator and the A29 20 GHz Doubler, and connect
a spectrum analyzer to the cable.
2. Tune the source frequency across the A28 YIG Oscillator range (3.2 GHz to 10 GHz) noting the
lowest power level.
3. Compare the measured level to the level shown on the RF Path Block Diagrams on page 1-109.
• If the power level is good, replace the A29 20 GHz Doubler.
• If the power level is bad, replace the A28 YIG Oscillator.
Microcircuit A26 MID
Connector
+12V +8V +10V +9V −5.2V +5.2V +15V −15V
A30 Modulation Filter J31
✔✔✔ ✔ ✔
A29 20 GHz Doubler J32
✔✔ ✔ ✔ ✔ ✔
A27 40 GHz Doubler J33
✔✔ ✔ ✔ ✔ ✔
A35 I/Q Modulator J34
✔✔ ✔ ✔ ✔ ✔
To Next Page
Loading...
Need help?
General
