Tektronix WFM2200A, Руководство пользователя

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Checking luma gamut
Luma limit thresholds can be configured for identifying luma exceeding
threshold limits. They apply to both the incoming SDI and to the Arrowhead
representation of the SDI input as a composite signal. By defining these levels in
percent, they automatically account for the presence or absence of setup. The
thresholds are affected by your choice of set-up or no set-up for the Arrowhead
display.
Set the thresholds for gamut. (See To set up gamut checks on page 202.) After
selecting the Arrowhead display, compare the signal to the display to determine
out-of-gamut luminance. Note the following:
■ The adjustable thresholds are indicated by the dark blue horizontal graticule
lines.
■ The thresholds are defined in terms of percent of full scale.
■ The range for the Upper limit is 90% to 108%.
■ The range to the Lower Limit is –6% to +5%.
Another useful Arrowhead function is a measure of how well the active video
signal is using the dynamic range of the video channel. A properly adjusted
signal should be centered in the arrowhead graticule and have transitions that
approach all the limits.
Automating gamut checks
You can use alarms to automatically monitor for out-of-gamut conditions.
1. Check that Gamut thresholds are configured as you want them. See To set up
gamut checks on page 202.
2. Press the CONFIG button to display the Configuration menu.
3. Select Alarms and then Video Content . A dialog box appears where you can
select for the various Video Content alarms.
4. Use the up/down arrow keys to move to each of the alarms that you want to
set. Press the
SEL button to toggle the alarm on (X) or off.
5. When you have configured the Alarms as you want them, move to the Select
here box and select it.
6. Back in the Alarms menu, check that Enable Alarms is set to On before
exiting the Alarms menu.
Checking gamut
206 WFM2300 and WFM2200A Waveform Monitors User Manual