Tektronix WFM 601i, User Manual

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Measurement Theory
3–24
WFM 601i Serial Component Monitor
B+G
B–G
–(R+G)
R–G
G
G
B
R
Figure 3-13: Construction of the Diamond GBR display.
Bowtie Display
The bowtie display provides a means of making a quick evaluation of relative
amplitudes and timing through the three channels. A special test signal is
required for this display. The Tektronix TSG- 422, Option 1S provides this type
of signal and a set of time marks to aid in signal evaluation. The signal is a 500
kHz sinewave on channel 1 (luminance) and 502 kHz sinewave on channels 2
and 3 (color difference signals). The display is made up of two separate
waveforms. See Figure 3-14. The first waveform compares channel 1 to channel
2. The second waveform compares channel 1 to channel 3. The generator
provides a center marker, which should correspond with the null point if
interchannel timing is correct. The time markers are from the generator and are
20 ns apart.