Agilent Technologies Signal Analyzer N9030a - Manual (Page 642)

6 RLC Swept SA Measurement Front-Panel & SCPI Reference
Input/Output
For the instrument to stay locked, the value entered must be within 5 ppm of the actual external
reference frequency. So it is important to get it close, or you risk an unlock condition.
Note that this value only affects the instrument’s ability to lock. It does not affect any calculations
or measurement results. See "Freq Offset" in the Frequency section for information on how to
offset frequency values.
Key Path Input/Output, Freq Ref In
Remote Command [:SENSe]:ROSCillator:EXTernal:FREQuency <freq>
[:SENSe]:ROSCillator:EXTernal:FREQuency?
Example ROSC:EXT:FREQ 20 MHz sets the external reference frequency to 20 MHz, but does not select
the external reference.
ROSC:SOUR:TYPE EXT selects the external reference.
Notes Still available with Internal selected, to allow setup for when External is in use.
Preset This is unaffected by a Preset but is set to 10 MHz on a "Restore Input/Output Defaults" or
"Restore System Defaults->All"
Min CXA: 10 MHz
EXA: 10 MHz or 13 MHz, depending on whether N9010A-R13 is licensed
MXA: 1 MHz
PXA: 1 MHz
Max CXA: 10 MHz
EXA: 10 MHz
MXA: 50 MHz
PXA: 50 MHz
Default Unit Hz
Initial S/W Revision Prior to A.02.00
External Reference Lock BW
This control lets you adjust the External Reference phase lock bandwidth. This control is
available in some models of the X-Series.
The PXA variable reference loop bandwidth allows an external reference to be used and have the
analyzer close-in phase noise improved to match that of the reference. This could result in an
improvement of tens of decibels. The choice of “Wide” or “Narrow” affects the phase noise at low
offset frequencies, especially 4 to 400 Hz offset. When using an external reference with superior
phase noise, we recommend setting the external reference phase-locked-loop bandwidth to wide
642 Remote Language Compatibility Measurement Application Reference