Basic Measurements
1760 SeriesComponent Waveform/Vector Monitor User Manu al
4-18
of checking timing. The signal sourcecan be adjusted until
the ellipse disappears,providing a very accurate method of
correcting timingerrors.
Timing errorsare indicated by the trace moving away from
the center timing dot. See Figure 4-15. For wide-band (≥1.5
MHz) component formats, the smaller spacings of dots repre-
sent approximately 40 ns of error; the larger spacing repre-
sents 80 ns. The timing dots representproportiona lly larger
errors for lower bandwidth signals.
For signals decoded from composite (bandwidth of approxi-
mately 500 kHz),the timing dots represent approximately
120 and 240 ns, respectively. The transitions will be “S”
shaped due to the narrow-band color difference signals. Note
that correct timing is alwaysindicated by a transition through
the center dot, regardless of the signal bandwidth.
If a trace appears “bent”toward the center of the display,
delay of the color difference signal is indicat ed. “Bending”
away from centerindicates an advance of the color differ-
ence signal relativeto luminance.
C
M
B
R
M
C
G
B
R
G
YL
Y
L
Approximate80 ns
delayof Channel 2.
Figure 4-15. Lightning display showing delay.