Keysight N1911A Programming Manual page 525

Reset condition
On reset, the manufacturer string is not affected.
Query
SYSTem:PERSona:MANufacturer?
The query returns the manufacturer string that was set.
Query example
SYST:PERS:MAN?
Error message
If the parameter string entered is not "Agilent Technologies" or "Keysight
Technologies", error -158, "String data not allowed" occurs.
N1911A/1912A P-Series Power Meters Programming Guide
Queries the manufacturer string that was set.
SYSTem Subsystem 12
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