Tektronix WFM2200A, User Manual

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Bowtie display
The Bowtie display allows you to look at interchannel timing between Y Pb and
Y Pr. The left side of the display compares Y and Pb; the right side compares Y
and Pr. The Bowtie display requires a test signal with slightly differing
frequencies on the chroma channels than on the luma channel.
If the bowtie patterns have a sharp null, and the null is at the center of each line,
the relative amplitudes and interchannel timing are correct. Interchannel timing
errors will move the position of the null:
■ A relative amplitude error will decrease the depth of the null
■ An incomplete null combined with an offset from center indicates both
amplitude and timing problems between the channels being compared
To access the
Bowtie display
1. Press and hold the MEAS button to open the Measure pop-up menu.
2. Use the arrow keys to select Display Type > Bowtie .
3. Press the MEAS button to close the pop-up menu.
Elements of the
Bowtie display
Figure 16: Bowtie display
■ Display : Shows the display type as Bowtie.
■ Y-axis units : The units for the y-axis depend on the test signal and the signal
format.
■ X-axis units : Shows the x-axis in microseconds/divisions.
Display modes
WFM2300 and WFM2200A Waveform Monitors User Manual 81