Stanford Research Systems SR785, Руководство по эксплуатации и программированию

Страница: 214 / 546

4-18 Swept Sine Frequency Menu
SR785 Dynamic Signal Analyzer
Generally, the Faster Threshold should be set to the desired amplitude resolution. In
order for skipping to occur, this should be something greater than the variations in the
flattest regions of the measurement.
Command: SFST (?) d {, i}
Slower Threshold
Set the Slower Threshold [0.05..6 dB].
If Auto Resolution is skipping points and a measurement differs from the previous
measurement by more than the Slower Threshold for EITHER channel, then the sweep
returns to the previously measured point and moves to the very next frequency point in
the sweep (with no skipping). The sweep continues from this point, speeding up if
allowed and slowing down when required. This ‘fills’ in skips in the sweep which vary
by more than the Slower Threshold.
Measurements which differ by more than the Faster Threshold on EITHER channel, but
less than the Slower Threshold on BOTH channels, maintain the present sweep speed.
Generally, the Slower Threshold should be set to less than half of the smallest desired
feature size (relative to the region before the feature). A good rule is to set the Slower
Threshold at twice the Faster Threshold.
Command: SSLO (?) d {, i}