R&S CMU200 Reference Frequence Unlocked message during selftest

[_Wim_]

Hi,

After a lot of searching for a R&S CMU200 or CRTU of recommended here on the forum, I finally found one that had the modules I wanted (I/Q-interface, option B17) and for a reasonably affordable price. Yesterday it arrived at my home.

When I run the selftest, during the test of the reference board, it briefly shows the message "reference frequency unlocked". However, it also shows "all tests passed" in the end. Is this behaviour normal, or does my unit have a problem.

Additional info: I have reset the unit to its default settings, and checked, it is configured to work with the internal reference. My unit has option B12 installed.

[TheSteve]

I can't for certain but I suspect that is actually part of the test - it unlocks it on purpose and then relocks again to verify its presence. I have seen Agilent perform similar tests.

[_Wim_]

That seems indeed a logical explenation. The error also isn't shown any more when I work with the unit, so probably it is indeed part of the test. That is a relief. Thanks for the feedback.