Illustration 3 : Acquiring Single Signals - Tenma 72-8710 Operating Manual

DSO Series User Ma nual

Illustration 3 : Acquiring single signals

The advantages and special features of your digital storage
oscilloscope lie in its ability to acquire non cyclical signals like pulse and
glitch. To acquire a single signal, you must have transcendental
knowledge of that signal to set the trigger level and trigger edge. For
example, if the pulse is a logical signal of TTL level, the trigger level
should be set at about 2V and the trigger edge should be set to rising
edge trigger. If you are not certain about the signal, you can observe it
by automatic or normal trigger to determine the trigger level and trigger
edge.
Steps :
1. As in the previous illustration, set the attenuation factor of the
probe and CH1.
2. Carry out trigger setup.
①
Press [TRIG MENU] in the trigger control zone to display the
trigger setup menu.
②
In this menu, use F1~F5 menus to set the trigger type to
EDGE, set trigger source to CH1, set inclination to RISING,
set trigger type to SINGLE and set trigger coupling to AC.
③
Adjust horizontal time base and vertical range to an
appropriate range.
④ Turn the [TRIGGER LEVEL] control knob to get the desired
level.
⑤ Press [RUN/STOP] and wait for a signal that meets the trigger
condition. If any signal reaches the set trigger level, the
system will sample once and display it on the screen. By
using this function you can easily acquire any occasional
event. For example, when a sudden glitch of relatively big
amplitude is acquired : set the trigger level to just higher than
the normal signal level. Press [RUN/STOP] and begin
waiting. When a glitch occurs, the machine will automatically
trigger and record the waveform immediately before and
after triggering. By turning the horizontal POSITION knob in
the horizontal control zone on the front panel, you can change
the trigger position horizontally to achieve negative delay
trigger of various lengths for easy observation of waveform
occurring before the glitch
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