Filter
Top Products
Chapter 2 73
Making Complex Measurements
Making Stimulus Response Measurements
Figure 2-2 Tracking Generator Output Power Activated
7. Put the sweep time of the analyzer into stimulus response auto
coupled mode by pressing
Sweep, Swp Coupling (SR). Auto coupled
sweep times are usually much faster for stimulus response
measurements than they are for spectrum analyzer (SA)
measurements. If necessary, adjust the reference level to place the
signal on screen.
NOTE In the stimulus response mode, the Q of the DUT can determine the
fastest rate at which the analyzer can be swept. (Q is the quality factor,
which is the center frequency of the DUT divided by the bandwidth of
the DUT.) To determine whether the analyzer is sweeping too fast, slow
the sweep and note whether there is a frequency or amplitude shift of
the trace. Continue to slow the sweep until there is no longer a
frequency or amplitude shift.
8. Decrease the resolution bandwidth to increase sensitivity by
pressing
BW/Avg, Res BW, and the step-down key (↓) until the
sensitivity is increased. In Figure 2-3, the resolution bandwidth has
been decreased to 30 kHz.
9. Narrow the video bandwidth to smooth the noise by pressing
BW/Avg, Video BW, and the step-down key (↓) until the noise is
reduced. In Figure 2-3, the video bandwidth has been decreased to
300 Hz.