Measuring Waveforms
CSA8000B & TDS8000B User Manual 3-85
Taking Cursor Measurements
Use cursors to measure amplitude and time quickly and with more accuracy than
when using graticule measurements. Because you position cursors wherever you
want on the waveform, they are easier to localize to a waveform segment or
feature than automatic measurements.
Time or amplitude or both. Vertical cursors measure time or bits on screen;
horizontal cursors measure amplitude: voltage, watts, rho, or ohms; and
waveform cursors measure both. Table 3--6 expands on these definitions.
Table 3- 6: Cursor functions (types)
Cursor function Parameter measured Cursor readout
Horizontal cursors
Horizontal cursors measure amplitude (volts, watts). Each cursor
measures with respect to:
Hv1 = Level at Cursor 1 with respect to its source ground level
Hv2 = Level at Cursor 2 with respect to its source ground level
H∆v = Level at Cursor 2 -- Level at Cursor 1
Level is cursor displacement from the source ground times the
source volts/div. Note that the two cursors may have different
sources and therefore can have different volts/div settings.
Vertical cursors
Trigger point Vertical cursors measure distance (time in seconds or bits). Each
cursor measures with respect to:
Ht1 = Time at Cursor 1 with respect to the trigger point
Ht2 = Time at Cursor 2 with respect to the trigger point
H∆t = Time at Cursor 2 -- Time at Cursor 1
H1/∆t = 1/(Time at Cursor 2 -- Time at Cursor 1)
Time is divisions of displacement of the cursor from its source trigger
point times the source time/div. Note that the two cursors may have
different sources and, therefore, can have different time base (Main,
Mag1, Mag2) settings.
Waveform cursors
Trigger point Waveform cursors measure both voltage and time. Each cursor is,
in effect, both a vertical and horizontal cursor. Neither of these paired
cursors can be moved off the waveform.
Note that sources can have different volts/div settings.
Why Use?