User`s guide

Description
The query returns the power-line reference frequency currently used by the
34410A/11A/L4411A analog-to-digital converter (50 or 60 Hz). When you
apply power to the instrument, the instrument automatically detects the
power-line frequency and uses this value to determine the integration time
used.
The command form allows you to override automatic detection and set
either 50 or 60 Hz. However, it is recommended that you use automatic
detection to ensure that the calibration is performed with the reference
frequency set to the line frequency in use. In special cases, the dominant
noise source in the operating environment may be at the other frequency
(or harmonic thereof) and an override may be appropriate.
For a more detailed discussion of the calibration
procedures, see the Agilent 34410A/11A/L4411A
Service Guide. Please refer to the Service Guide before
attempting to calibrate the instrument. Improper use of
the CALibration commands can adversely affect the
accuracy and reliability of the instrument.