Tektronix TG700, Руководство пользователя

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HD3G7 HD 3 Gb/s SDI Video Generator
Zone plate signal Pattern control parameter
Circle Circle frequency: [x] c/aph 1
Diagonal
Diag. Frequency: [x] c/aph
1
H Sine
Horiz. Frequency: [x] MHz
H Sweep H Sweep Frequency: [x] MHz
V Sine Vert. Frequency: [x] c/aph 1
V Sweep V Sweep Frequency: [x] c/aph 1
1
c/aph = cycles per active picture height
4. While the pattern control parameter is displayed, you can use the left ( ◄ )
or right ( ► ) arrow button to modify it. This will modify the signal while
maintaining the basic pattern.
NOTE. Press the left ( ◄ ) and right ( ► ) arrow buttons at the same time to reset
any parameter.
5. Use the up ( ▲ ) or down ( ▼ ) arrow button to scroll through the parameters
menu which, for the prede fi ned signals, starts with it’s unique pattern control
parameter as shown in the table above, and then continues through the list
of dependent parameters. At each parameter, whether it’s a pattern control
parameter or a dependent parameter, you can use the left (
◄ ) or right ( ► )
arrow button to modify it.
6. When you are done altering parameters, scroll to the Save As: selection, at
the bottom of the menu and use the left ( ◄ ) or right ( ► ) arrow button to
select User Custom 1 or User Custom 2 .
7. Press the ENTER button to save the modi fi ed signal.
Zone Plate Pattern Control Parameters
Zone plate patterns are made up of sinusoidal variations
2
in luminance, with the
“peaks” of the sine waves resulting in white areas on the video screen and the
wave “troughs” shown as gray or black. The cycles can occur in all three of the
video dimensions: horizontally, or along each line of the picture; vertically, or
“down” the video frame; and temporally (with time). The three dimensions are
often referred to by the shorthand designations of X, Y, and T.
2
Zone plate variations can be sinusoidal, square, or triangular. These discussions of zone plated parameters will
refer to sinusoidal variations for convenience.
The luminance of any point in the picture, physically on the screen and in time, is
determined by the value of sine at that particular point; the value of sine follows
from the phase of the cycle at that point; and (by the de
fi nition of a zone plate)
the phase of any point is determined by the equation:
3–152 TG700 TV Signal Generator Platform User Manual