Review the General Troubleshooting recommendations before proceeding with this section.
This troubleshooting procedure assumes the PNA successfully passed the Power Level Accuracy (Source Power Accuracy) Performance Test. A failure in this test is often due to drift in the source linearity performance. To reset the coefficients which control this performance, perform the Source Calibration Adjustment.
You should not see a source unlevelled error reported on the PNA display during this test. If this error occurs and the test fails, first fix the source unlevelled problem. If phaselock lost errors appear on the PNA display during the test, it is usually best to perform a Receiver Calibration Adjustment. The linearity of the PNA receiver is the standard against which the source linearity is checked.
If failures continue, replace the source. Refer to the appropriate PNA service guide for replacement procedures.