Why does my E6651A fail Source Modulated Power Level Accuracy in TME?

A compatibility issue exists between E6651A firmware versions 5.6.1.0/6.6.1.0 and TME release 1.0.

The issue affects the Source Modulated Power Level Accuracy test, causing all datapoints to fail by a significant amount. The test limit is ±1.4dB, and failures in the region of +3dB are common with this issue.

The workaround for this issue is to downgrade the firmware to 5.5.1.0/6.5.1.0, test the E6651A, and upgrade the firmware back to 5.6.1.0/6.6.1.0 once the procedure is complete.

This issue has been logged in our software quality system, and will be fixed in due course.