Magni AVM-510A Series, Руководство оператора

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Viewing Waveforms, Vectors, and Pictures
7-4
Waveform Limit Lines
Waveform limit lines cause the waveform to turn red each time a portion of it goes outside a pre-
determined set of limits. Two specific limits can be set: an upper limit for peak video and a lower limit
for sync tip.
When an upper limit is set, the waveform turns red every place the signal exceeds the upper limit,
including the vertical limit. For example, if you have a vertical interval test signal, such as modulated
ramp, where the chroma or any part of the signal exceeds the upper limit, this area also appears red.
The lower limit includes sync tip, burst, and any part of the input signal that goes below the set limit. If
you set the limit above the middle of sync and the bottom of burst, some of the color bars will be red
at the bottom of the waveform.
Added Marks
Added marks helps determine various limits in the horizontal interval. Marks include: horizontal sync
width, horizontal blanking, and burst amplitude and position. Note that these marks are only visible in
2H Mag and cannot be adjusted.
To see added marks (Figure 7-3):
1. Press the
Sweep
button until the 2H LED lights.
2. Press the
H Mag
button to horizontally magnify the sweep.
3. If you do not see the boxes, press the
Config
button to access the Configure menu.
4. Select DISPLAY and then press the
Enter
button.
5. Select GRATICULE OPTIONS and then press the
Enter
button.
6. Select ADDED MARKS and then press the
Enter
button.
7. Select MARKS to turn added marks ON/OFF.
Once visible, adjust the waveform vertically so the blanking level rests on the zero graticule line.
Position it horizontally so the leading edge of the sync passes through the + mark on the screen. The
remaining parts of the signal should be visible as shown in Figure 7-3.
Figure 7-3. Added Marks Box Locations