Agilent Technologies X Series Manual page 454

Input/Output
Key Path
Example
Readback
Initial S/W Revision
Internal
The internal reference is used.
Key Path
Example
Readback
Initial S/W Revision
External
The external reference is used.
Key Path
Example
Readback
Initial S/W Revision
Ext Ref Freq
This key tells the analyzer the frequency of the external reference. When the external reference is in use
(either because the reference has been switched to External or because the Reference has been switched
to Sense and there is a valid external reference present) this information is used by the analyzer to
determine the internal settings needed to lock to that particular external reference signal.
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
Remote Command
Example
454
Input/Output, Freq Ref In
:ROSC:SOUR:TYPE SENS
Sense
Prior to A.02.00
Input/Output, Freq Ref In
:ROSC:SOUR:TYPE INT
Internal
Prior to A.02.00
Input/Output, Freq Ref In
:ROSC:SOUR:TYPE EXT
External
Prior to A.02.00
Input/Output, Freq Ref In
[:SENSe]:ROSCillator:EXTernal:FREQuency <freq>
[:SENSe]:ROSCillator:EXTernal:FREQuency?
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.