Single - Velleman EDU08 Guide Rapide

The display will look like this:
Before we can adjust the trigger level we have to change the function of
the UP/DOWN keys from setting VOLT/Div to 'changing the trigger level':
Now we can change the trigger level by pressing the UP or DOWN keys.
The slope symbol also indicates the trigger level.
If you move the trigger level to the the center position, the trace will become
unstable, because it no longer triggers on a single point, but anywhere between
a falling and a rising edge of the signal:
If you move the trigger level to a point lower than the signal, the scope will
no longer refresh the trace, as the trigger level is no longer reached.
Now, lets change the slope:
Look closely at the signal now (A), do you see the difference with the
previous screenshot of our signal (B)?
A
B

Single:

Sometimes, you would like to 'capture' a certain event, instead of continuously
looking at a signal. This can be done by choosing 'Single' instead of 'Run' as
the Run mode. The scope will start drawing the trace when the trigger level
and slope are reached and when it reaches the right hand side of the screen,
it will stop drawing and switch to 'HOLD'-mode. Press the 'HOLD'-button
again to 're-arm' the trigger and wait for the next event to happen.
Try the following experiment:
• Disconnect the red alligator clip from the 'test'-pin.
• Turn the scope off and on again, so that all setting are set to default.
• Select following items from the menu: 0.1V/div, 0.1ms/div and Adjust
Trg Level.
Next, leave the menu and set the trigger level as shown below:
Enter the menu and select 'Single' as the trigger mode.
The display will look more or less like below:
Now, touch the red alligator clip with your finger. Your body acts like an
antenne and touching the clip will induce 'noise' to the input of the scope.
The unit will trigger and the display will show a single screen of the noise
you've injected trough your finger. Next, the scope will switch to 'HOLD'-
mode. Now you have plenty of time to study the screen.
To capture the next event, press the 'HOLD'-button briefly.
Triggering is re-armed and when you touch the red alligator clip again, the
screen will refresh:
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EDU08 Getting started
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