Specifications

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Recording transient events
One of the most important advantages of a digital oscilloscope over an analog oscilloscope is the ability
of the digital scope to capture transient (i.e., one-time or infrequent) events and display them.
As mentioned above, this is necessarily done with real-time sampling. The steps to acquire a transient
waveform are:
1. Set the scope's vertical amplifier(s) to the desired gain and coupling configuration.
2. Set the scope to trigger on the signal you wish to capture.
3. Set the timebase to capture the temporal detail you want.
4. Arm the scope's trigger and wait for it to trigger.
5. After the scope has triggered, analyze or save the captured waveform.
While this description of the measurement process sounds straightforward, in practice it can sometimes
be difficult to set up the trigger circuit appropriately. This can be caused when you don't know much
about the waveform's characteristics and the waveform occurs infrequently.
Video triggering
Most modern oscilloscopes have the ability to trigger on video signals from various video standards.
Perhaps the most common are the NTSC and PAL/SECAM signals used on the original black and white
or color televisions, although these are being used less because of the newer digital formats.
The typical trigger synchronization abilities for video triggering are: odd fields, even fields, all lines, and
line number. The following picture shows an example of a single video line from an NTSC video signal:
Figure 26
Averaging
A measurement mode of digital oscilloscopes allows you to average a set of readings together, which
can reduce the effects of random noise on signals. The typical digital oscilloscope lets you average
from 2 times to 256 times (in steps of powers of 2) and then display the resulting waveform.
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