Absolute Amplitude Accuracy Troubleshooting

Related Adjustments

• 50 MHz Calibrator Amplitude Adjustment

Perform the 50 MHz Calibrator Adjustment if this test fails. If the adjustment does not cure the problem, suspect a hardware failure. See the analyzer Service Guide for troubleshooting information. Assemblies that can cause a failure are anything in the Lowband signal path, especially the input attenuators or A13 Front End Assembly.

This test might fail due to incorrect calibration data of the 8494 and 8496 step attenuators. Make sure you have entered the calibration data for the step attenuators that you're using. Please refer to the Enter Equipment Calibration Data section in the TME help for details on how to enter this data. You must enter the data for the following columns to obtain valid results: Attn(dB), Uncert(dB), and ReflSize.

Some of the measurement applications (EMI for instance) allow amplitude corrections for external losses (Cable Loss as an example). These corrections appear under the Input/Output > More > Corrections menu. If corrections are set to ON, then the Absolute Amplitude Accuracy Test will fail. A System Preset will not turn off these corrections, and TME cannot detect if corrections are present. If this test fails, then this may be the cause. To manually turn off these corrections, change the setting to OFF by pressing Input/Output > More > Corrections > Off.