Agilent Technologies E8257D PSG User Manual page 60

Basic Operation
Configuring the RF Output
The signal generator provides a softkey, Sweep Retrace Off On, that lets you configure single sweep
behavior. When sweep retrace is on, the signal generator will retrace the sweep to the first point of
the sweep. If the sweep retrace is off, the sweep will stop and remain on the last point in the sweep.
Activating Scalar Pulse in Sweep Configurations
If your sweep setup uses a scalar network analyzer and an AC detector, the PSG must modulate the
swept signal with a 27 kHz square wave, also referred to as a scalar pulse. This pulse modulation is
necessary for the AC detector to properly detect the swept signal. If the PSG is controlled by an
8757D through a GPIB connection, the scalar pulse automatically turns on when AC detection is
selected on the 8757D. When using any other scalar analyzer, you can manually turn on the scalar
pulse using either one of the following key–press sequences:
Press
Sweep > Configure Ramp/Step Sweep > More > Scalar Pulse Off On to On
or
Press >
Pulse Pulse Source
Using Step Sweep
Step sweep provides a linear progression through the start–to–stop frequency and/or amplitude
values. You can toggle the direction of the sweep, up or down. When the
is set to Up, values are swept from the start amplitude/frequency to the stop amplitude/frequency.
When set to Down, values are swept from the stop amplitude/frequency to the start
amplitude/frequency.
When a step sweep is activated, the signal generator sweeps the RF output based on the values
entered for RF output start and stop frequencies and amplitudes, a number of equally spaced points
(steps) to dwell upon, and the amount of dwell time at each point; dwell time is the time that the
signal is settled and you can make a measurement before the sweep moves to the next step. The total
time at any step is the sum of the switching speed (from the datasheet) plus the dwell time at that
step. The frequency, amplitude, or frequency and amplitude of the RF output will sweep from the
start amplitude/frequency to the stop amplitude/frequency, dwelling at equally spaced intervals
defined by the
# Points
To Configure a Single Step Sweep
In this procedure, you create a step sweep with nine, equally spaced points, and the following
parameters:
• frequency range from 500 MHz to 600 MHz
• amplitude from −20 dBm to 0 dBm
• dwell time 500 ms at each point
1. Press .
Preset
2. Press .
Sweep/List
This opens a menu of sweep softkeys.
3. Press
Sweep Repeat Single Cont
This toggles the sweep repeat from continuous to single.
4. Press
Configure Step Sweep.
5. Press >
Freq Start 500
46
> >
Scalar Pulse Off On
softkey value.
.
> .
MHz
to On
softkey
Sweep Direction Down Up
Chapter 2