Tektronix CSA7154, Руководство пользователя

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Measuring Waveforms
3- 164
CSA7000 Series, TDS7000 Series, & TDS6000 Series Instruments User Manual
First point in record
Delay
Trigger point of
cursor source
Horizontal divisions
×
sec/div
+
Cursor
Cursor readout (tn) =
Horizontal reference = 0%
Figure 3- 38: Components determining Time cursor readout values
Note that a vertical cursor readout includes and varies directly with the Time-to-
First-Point component, which varies directly with the horizontal position set for
the timebase. To see the amount of time to the first point, set Horizontal DELAY
to 0.0 and set Horizontal Ref to 0%. Now the Horizontal position readout shows
the time following the first point, and adding this value to the cursor readout
yields the cursor position on screen relative to first point. (You can find the
horizontal readout both in the control window and in the readout at the bottom of
the screen.) The following relationships hold:
Time from First Point = Horiz. Position (when Horiz. Delay and Ref Position are
zero)
T1 readout = Time to First Point + Additional Time to Cursor
Cursor Units Depend on Sources.
A cursor that measures amplitude or time will
read out in the units of its source as indicated in Table 3--10. Note mixed sources
require Delta--Cursor readouts to follow units of the cursor 1 source.