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Oscilloscope terminology
Noise: Undesired random addition to a signal.
Ripple: Unwanted periodic variation of a DC voltage.
Rising or falling slope: It determines where the scope will trigger. This can be on the rising or on the falling slope of the signal.
falling slope
rising slope
RUN or RUN-mode: When in RUN-mode, the screen is continuously updated with new data.
Sample rate: Usually expressed in samples or megasamples/second, sometimes in MHz. It is the number of times per second the digi-
tal oscilloscope 'looks' at the signal at the input. The more it 'looks', the better it is able to recreate a faithful image of the waveform on the
screen. Theoretically the sample rate needs to be twice the max. frequency of the applied signal, however, for best results a sample
rate of 5 times the max. frequency is recommended. The EDU08 samplerate is max. 1MS/s for repetitive signals, 100kS/s in real time.
Signal: Voltage applied to the input of the oscilloscope. The subject of your measurement.
Sine wave: Mathematical function that represents a smooth repetitive oscillation. The waveform shown at the start of this glossary is a sine wave.
Spikes: Fast, short duration transients in a signal.
Trigger: Triggering is a technique used to get a stable image on the screen. This is achieved by making sure that the scope always starts to draw the
trace at the exact same point, represented by a certain level of the signal. By doing so, every waveform is drawn on top of the previous one and sideways
scrolling of the trace is prevented.
Trigger level: Determines the level the signal has to reach before the scope triggers. By setting a certain trigger level, you can filter events and only display
the events you want to display.
Vrms: The rms voltage of an AC source represents the required DC voltage to generate the same amount of heat in a resistor as the AC source would
do. For sinusoidal signals, Vrms = Vpeak / sqrt(2).
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