Agilent Technologies N5171B Command Reference Manual page 246

Analog Modulation Commands
Frequency Modulation Subsystem–Option UNT ([:SOURce])
This command sets the step increment for the FM deviation of the signal generator.
*RST +5.00000000E+003
Key Entry Incr Set
Remarks The setting enabled by this command is not affected by signal generator power- on,
preset, or *RST.
216 Agilent X-Series Signal Generators SCPI Command Reference