
To analyze video waveforms with Option 005
The combination of the TV trigger, delayed sweep, and automatic
measurements allow this oscilloscope to precisely analyze video waveforms.
There is no need for external clamping to obtain a stable trigger when you
are viewing unclamped video signals. This is because the TV sync separator
in the oscilloscope has an internal clamp circuit in the trigger path. Because
there is no clamp in the vertical path of your oscilloscope, you will be able to
observe any DC level shifts in the video on the oscilloscope display. To
eliminate this position shifting as the DC component of the video changes,
select AC coupling.
For this exercise, we connect the oscilloscope to the video output terminals
on a television. We set up the oscilloscope to view the second vertical
interval with delayed sweep windowed on the vertical interval test signals
(VITS). Then we make windowed measurements with the delayed sweep.
1
Connect a TV signal to channel 1, and select channel 1 as your trigger
source.
2 Press Slope/Coupling in the TRIGGER section of the front
panel, then press the
TV softkey.
3 Select the desired TV Standard, such as NTSC, PAL, or SECAM.
Use NTSC instead of PAL-M
To trigger on a PAL-M signal, use NTSC. The line and field rates are identical.
4
Press Mode , then press the Video Autoscale softkey.
Using Option 005 Enhanced TV/Video Trigger
To analyze video waveforms with Option 005
3–16
Comentarios a estos manuales