Tektronix 1760 用户手册
Basic Measurements
1760 Series Component Waveform/Vector Monitor User Manual
4-18
of checking timing. The signal source can be adjusted until
the ellipse disappears, providing a very accurate method of
correcting timing errors.
the ellipse disappears, providing a very accurate method of
correcting timing errors.
Timing errors are indicated by the trace moving away from
the center timing dot. See Figure 4-15. For wide-band (
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 represent proportionally larger
errors for lower bandwidth signals.
sent approximately 40 ns of error; the larger spacing repre-
sents 80 ns. The timing dots represent proportionally 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 always indicated by a transition through
the center dot, regardless of the signal bandwidth.
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 always indicated 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 indicated. “Bending”
away from center indicates an advance of the color differ-
ence signal relative to luminance.
delay of the color difference signal is indicated. “Bending”
away from center indicates an advance of the color differ-
ence signal relative to luminance.
C
M
B
R
M
C
G
B
R
G
YL
YL
Approximate 80 ns
delay of Channel 2.
delay of Channel 2.
Figure 4-15. Lightning display showing delay.