Technical data
4-38 Service Guide N5230-90025
Troubleshooting PNA Series Microwave Network Analyzers
Measurement System Troubleshooting N5230C
Checking the Signal Separation Group
Before checking the signal separation group, perform the following procedures:
• “Getting Ready to Test” on page 4-30
Checking the Output Power of the A, B, C, and D Signals
Using a power meter, you can measure the outputs of the A, B, C, and D signals from the front panel. The
measurement results will help you isolate a faulty assembly. The output of the R channel cannot be
measured because it would necessitate breaking the phase lock loop, causing all of the signals to be lost.
Equipment Used for These Tests
Equipment Setup
1. Before starting these checks, zero and calibrate the power meter. (See the power meter user’s guide for
instructions on setting the calibration factor.)
2. If the
Receiver Display (Figure 4-7 or Figure 4-8) is not on the analyzer screen, perform the following: On
the
System menu, point to Service, Utilities, and then click Receiver Display.
3. Set the sweep speed for a 10 second sweep: On the Sweep menu, click Sweep Time and set the time to
10.000 seconds in the
Sweep Time box.
Checking Port 1, 2, 3, or 4 Power Outputs (A, B, C, or D Signals)
The object of this check is to verify the power of the output signal across the entire frequency range.
Perform this test if there is an observed problem only with one channel trace. The ten second sweep is slow
enough to allow you to observe the output power on the power meter as the sweep occurs.
1. Connect the power sensor to the suspect port.
2. Observe the power reading on the power meter as the sweep occurs on the analyzer.
3. The measured output power on the power meter should be at least –8 dBm over the entire frequency
range.
• If the measured power is correct, go to “Checking the Receiver Group” on page 4-42.
• If the measured power is not correct, go to “Checking the Signal through the Signal Separation Path”
on page 4-39.
Equipment Type
Model or
Part Number
Alternate Model or
Part Number
Power meter E4418B/E441B E4418A/E4419A
Power sensor, 3.5 mm E8485A None
Adapter, 3.5 mm (f) to 3.5 mm (f) 83059B 85052-60012