Measurements
1780R-Series Operator’s Manual 4–27
Chroma / Luma Measurements with Lissajous Display
The Lissajous display is an X/Y plot of the sine-squared luminance
pulse versus the sine-squared envelope of the demodulated
chrominance. This display is useful when signals have previously
been transcoded into a component format, so that R–Y and B–Y may
be unequally delayed with respect to luminance.
While still in the Chroma / Luma measurement mode, touch
<VECT / C/Y> to outline <VECT>.
Set large knob function to phase control by touching the <PHASE>
area of the vectorscope CRT.
Using the large knob to set phase, set the burst vector to the
9o’clock position for an R–Y versus luminance display, or to the
6o’clock position for a B–Y versus luminance display.
If there are no chrominance-to-luminance errors, the Lissajous
display will show a straight line at 45_.
Phase delay causes separation of the display.
Gain inequalities cause displacement of the display end points.
Measurements
1780R-Series Operator’s Manual 4–27
Chroma / Luma Measurements with Lissajous Display
The Lissajous display is an X/Y plot of the sine-squared luminance
pulse versus the sine-squared envelope of the demodulated
chrominance. This display is useful when signals have previously
been transcoded into a component format, so that R–Y and B–Y may
be unequally delayed with respect to luminance.
While still in the Chroma / Luma measurement mode, touch
<VECT / C/Y> to outline <VECT>.
Set large knob function to phase control by touching the <PHASE>
area of the vectorscope CRT.
Using the large knob to set phase, set the burst vector to the
9o’clock position for an R–Y versus luminance display, or to the
6o’clock position for a B–Y versus luminance display.
If there are no chrominance-to-luminance errors, the Lissajous
display will show a straight line at 45_.
Phase delay causes separation of the display.
Gain inequalities cause displacement of the display end points.