Agilent Technologies E1441A user service Sweep Trigger Source External Sources, Internal Source

start frequency to the stop frequency. The number of frequency points in the sweep depends on the sweep time you select and is automatically calculated by the function generator.

Sweep time: 1 ms to 500 seconds. The default is 1 second.

The function generator computes between 2,048 and 4,096 frequency points from the start frequency to the stop frequency.

Use the following command to set the sweep time:

SWEep:TIME <seconds>MINimumMAXimum

Sweep Mode You can sweep with either linear or logarithmic spacing. The output frequency of a linear sweep changes linearly during the duration of the sweep. For logarithmic spacing, the output frequency changes exponentially during the duration of the sweep.

Sweep mode: Linear or Logarithmic. The default is Linear.

Use the following command to set the sweep mode:

SWEep:SPACing LINearLOGarithmic

Sweep Trigger Source External Sources

In the triggered sweep mode (TRIG:SOUR other than IMMediate), the function generator outputs a single sweep each time a trigger is received. After one sweep from the start frequency to the stop frequency, the function generator waits for the next trigger while outputting the start frequency.Figure 2-8shows the frequency sweep operation with "external" trigger (IMMediate, EXTernal, TTLTRG<n>, or BUS). The default is IMM.

Frequency Sweep Output

sweep start

frequencyidle at start sweep stop

frequency

frequency

begin sweep begin sweep

Sweep Trigger Signal (TRIG:SOUR is EXT BUSTTLTRG<N>)

Figure 2-8. Frequency Sweep with "EXTernal" Trigger

Internal Source

When the internal trigger source is selected (TRIG:SOUR IMMediate), the function generator repeatedly outputs a frequency sweep at a rate

44 Agilent E1441A Application Information Chapter 2