Pausing and Single-Stepping a Measurement

When continuous sweep is selected, Pause/Single functions as a pause/continue button. Click Pause/Single to pause the measurement; click Pause/Single again to continue the measurement.

When single sweep is selected, Pause/Single functions as a single-sweep button. Click Pause/Single to perform a single measurement sweep. Clicking Pause/Single when a sweep is in progress has no effect. The VSA will wait until the sweep is finished before beginning a new sweep.

When hardware triggering is enabled (set to anything besides Free run) and Pause/Single is clicked, the VSA waits for the measurement hardware to trigger before performing the single sweep.

When playback triggering is enabled (set to anything besides Free run) and Pause/Single, the VSA immediately searches for the next trigger.

The measurement control buttons in the toolbar or in the Control menu only apply to the selected measurement. To start or pause multiple measurements, use the buttons on the Measurements dialog.

Viewing paused data

When a measurement is paused, the most recent measurement data is preserved in RAM. Due to this, the "paused" data can be viewed in different ways. In fact, these operations can still be performed:

Any time-gating operation
Any Trace menu operation
Most marker operations
Any Window menu operation

For example, a different trace data types (from the main menu, click Trace > Data), different coordinates (click Trace > Format), or change the scaling or units (click Trace > Y Scale or Trace > X Scale) can still be selected. Or a marker added and any marker operation performed such as the band power calculation.

Changing measurement parameters

When a measurement is paused, be aware of the following when changing measurement parameters (measurement parameters are located under MeasSetup on the main menu):

Measurement changes take effect immediately, which may make the measurement data questionable. Because of this, the VSA shows the DATA? trace indicator when you change most measurement parameters.
Some measurement changes clear any existing data.
Changes to time-gating parameters are permitted. These changes take effect immediately and yield a valid answer.

Changing input parameters

Input changes take effect immediately, which may make measurement data questionable for a paused measurement. The VSA shows the DATA? trace indicator when most Input parameters are changed during a paused measurement.

Averaged measurements

The operation of Pause/Single remains the same for averaged measurements:

If continuous sweep is selected, pauses (or resumes) the averaged measurement.
If single sweep is selected, Pause/Single performs the next sweep and combines the results with the current average.

When Repeat Averaging is enabled, and for non-continuous average types that stop when the number of averages N (specified by Count) are completed, the behavior of Pause/Single is slightly different, as shown in the following table:

Repeat Averaging	Sweep	Clicking Pause/Single...
OFF	single	Adds another average to the total (N + 1).

OFF	continuous	Performs another N averages (includes the results from previous averages).

ON	single	If N averages have not been reached, adds another average to the total (N + 1); otherwise, performs the first sweep of a new, averaged measurement.

ON	continuous	Pauses or resumes the averaged measurement.