Acquiring and Displaying Waveforms
3–14
TDS 684A, TDS 744A, & TDS 784A User Manual
To change the horizontal scale and position:
1. Turn the horizontal POSITION and horizontal SCALE knobs. (See
Figure 3–8.)
2. If you want the POSITION knob to move faster, press the SHIFT button.
When the light above the shift button is on and the display says Coarse Knobs
in the upper right corner, the POSITION knob positions waveforms more
quickly.
Figure 3–8: Horizontal Controls
When you select a channel, the horizontal SCALE knob scales all channel
waveforms displayed at the same time. If you select a math or reference
waveform, the knob scales only the selected waveform.
When you select a channel, the horizontal POSITION knob positions all channel,
reference, and math waveforms displayed at the same time when Horizontal Lock is
set to Lock in the Zoom menu. See Zoom a Waveform on page 3–38.
To select the waveform record length and the trigger position, use the Horizontal
menu. You can also use this menu to change the horizontal position or scale
instead of using the horizontal knobs. You can select the delayed time base (see
Delayed Triggering on page 3–80) or choose the frames on the waveform that
you want to see (see Using FastFrame on page 3–46).
Trigger Position. The trigger point marks time zero in a waveform record. All
record points before the trigger event make up the pretrigger portion of the
waveform record. Every record point after the trigger event is part of the
To Change Horizontal
Parameters
