Agilent Technologies X Series Manual page 555

Example
Preset
State Saved
Initial S/W Revision
LO
When Gate is set to On, the LO sweeps whenever the gate conditions as specified in the Gate menu are
satisfied by the signal at the Gate Source.
This form of gating is more sophisticated, and results in faster measurements. With Gated LO, the
analyzer only sweeps while the gate conditions are satisfied. This means that a sweep could take place
over several gate events. It would start when the gate signal goes true and stop when it goes false, and
then continue when it goes true again. But since the LO is sweeping as long as the gate conditions are
satisfied, the sweep typically finishes much more quickly than with Gated Video.
When in zero span, there is no actual sweep performed. But data is only taken while the gate conditions
are satisfied. So even though there is no sweep, the gate settings will impact when data is acquired.
Key Path
Dependencies
Readback
Initial S/W Revision
Video
When Gate is set to On, the video signal is allowed to pass through whenever the gate conditions as
specified in the Gate menu are satisfied by the signal at the Gate Source.
This form of gating may be thought of as a simple switch, which connects the signal to the input of the
spectrum analyzer. When the gate conditions are satisfied, the switch is closed, and when the gate
conditions are not satisfied, the switch is open. So we only look at the signal while the gate conditions
are satisfied.
With this type of gating, you usually set the analyzer to sweep very slowly. In fact, a general rule is to
sweep slowly enough that the gate is guaranteed to be closed at least once per data measurement interval
(bucket). Then if the peak detector is used, each bucket will represent the peak signal as it looks with the
gate closed.
Key Path
Dependencies
Readback
SWE:EGAT:METH FFT
LO
Saved in instrument state
Prior to A.02.00
Sweep/Control, Gate, Method
Key is unavailable when Gate is On and FFT Sweep Type manually selected.
When selected, Sweep Type is forced to Swept and the FFT key in Sweep
Type is grayed out.
LO
Prior to A.02.00
Sweep/Control, Gate, Method
Key is unavailable when Gate is On and FFT Sweep Type manually selected.
When selected, Sweep Type is forced to Swept and the FFT key in Sweep
Type is grayed out
Video
Sweep/Control
555