11
MORDAX : DATA
User Guide
SYS V. 01.00.00
BOOT V. 01.00.00
Updated: 161229
Triggering
Triggering is one of the most important concepts to understand when using an oscilloscope. The trigger controls the
oscilloscope’s “horizontal sweep”; in other words, it controls the display window of the incoming signal. The trigger can be used
to synchronize the oscilloscope’s display with an incoming repeating signal (e.g., an oscillator’s waveform), allowing for clear
viewing and measurement.
The DATA’s oscilloscope currently has two trigger modes available: AUTO (automatic trigger) and NORM (normal trigger). The
AUTO mode continuously samples the incoming signal and triggers at a fixed rate, based on the currently selected time scale.
The NORM mode continuously samples the incoming signal, but will only generate a trigger event when the signal crosses the
trigger level.
In NORM mode, if the signal does not cross the trigger level, the screen will not change.
When to use trigger mode NORM -
Viewing repeating, high frequency signals, such as audio-rate waveforms (typical oscillator
output). The oscilloscope time scale would be set at 10ms or less.
When to use trigger mode AUTO -
Viewing slower signals like slower envelopes, low frequency oscillators (LFOS). Also
useful for viewing non-repeating higher frequency signals, like your main audio outputs (mix of many oscillators and FX). The
oscilloscope time scale would typically be set at 10ms or more.
*Always use trigger mode AUTO when your time scale is set to large values (e.g., 100’s of miliseconds or seconds)
Trigger Example - AUTO vs NORM
The images 1, 2, and 3 show an audio-
rate sinewave coming in on channel 1,
with the TRIG mode set to AUTO and a
TIME scale of 1ms. Note the distortion of
the sinewave in each image, this is due to
the triggering of the waveform being out
of sync with the AUTO mode trigger rate.
Pressing button 2-2 displays the TRIG
pop-up menu (image 3). Switching the
mode to NORM syncronizes the display
with the waveform, producing a trigger
event every time the waveform crosses
the trigger level (currently set at 3.14V).
Now that the oscilloscope is triggering off
of channel 1 the distortion is gone (image
4). You can even change the frequency
of the incoming sinewave and its relative
position will remain centered on the
screen.
1
2
4
3
*Note that if the incoming signal changes so that it never reaches the trigger level (3.14V in this case), the displayed
waveform will not update. For this reason, it’s advisable to start viewing a signal of unknown amplitude or shape in
AUTO mode, adjust parameters such as the trigger level and time scale, and then switch to NORM mode.
