Tektronix WFM 601i, User Manual

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Graticules
3–2
WFM 601i Serial Component Monitor
There are three dashed lines on the graticule. The line at 50% amplitude is the
center line for the color difference signals. The lines at 90 mV and 610 mV
correspond to the peak excursions for 75% amplitude color difference signals.
100% amplitude color difference signals extend from the baseline (0V) to 700
mV, centered on the 50% graticule line.
K-Factor line-time distortion is measured from the largest deviation of the bar
top (tilt or rounding) within the structure located just right of center, on the 700
mV line. The structure is designed to ignore the first and last 1
m
s of the bar
where short-time distortions (ringing, overshoot, undershoot, etc.) occur. The
solid outer box equals a 4% K factor, while the dashed line inner box equals a
2% K factor. For signals with a bar half-amplitude duration that exceeds 18
m
s,
measure the bar top in increments by positioning the bar to the left or right from
the leading or trailing edge.
2T pulse-to-bar measurements are made using the solid and dashed lines located
to the left of K Factor box. These lines are scaled according to the following
formula:
1 and 1
(1–4K) (1+4K)
Where:
K = 0.02 for 2% K Factor (using the dashed lines)
K = 0.04 for 4% K Factor (using the solid lines)
The VERTICAL X5 GAIN increases the resolution to 0.4% and 0.8%.
Horizontal Scale.
The horizontal reference line is also referred to as the reference
line, base line, 0% line, 0 mV, zero line, blanking level, and black level. The
reference line is 12 major divisions long with main marks at the 1st, 6th, and
11th divisions for timing and linearity measurements within the center ten
divisions on the scale. When the sweep button is set to 1 line, each major
division represents 5
m
s, minor divisions equal 1
m
s; when set to 2 line sweep,
each major division represents 10
m
s, minor divisions equal 2
m
s.
When the sweep is magnified the scale on the baseline equals 1 s per major
division and 200 ns per minor division in 2 line sweep, and 500 ns per major
division and 100 ns per division for 1 line sweep.