When E8257D powered ON, it is displaying "PROTOCODE:NOT FOR CUSTOMER USE" what does it mean ?
This usually means that the installed firmware is a beta version, try updating it.
The download and instructions are found here: E8257D, E8257N, E8267D, E8663D PSG Signal Generator Firmware | Keysight (formerly Agilent’s Electronic Measurement)
Hope this helps!
Protocode can be one of two things. When code is under development it's considered protocode, and when code is being customized for a specific customer need it will show as protocode. My recommendation is to go ahead and upgrade the firmware to the latest revision.
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