Tektronix AWVG1, User Manual, Page: 92 / 116

Appendix C: Zone Plates
C- 4
AWVG1 Wideband Video Generator User Manual
Figure C- 3: A KX-only zone plate
TG 2000 display: KX 2 (H sweep)
Units: c/aph
2
(cycles per active picture height squared)
This parameter sets the increase (or decrease) in the horizontal frequency as a
function of position along the video line. When K
X2
alone is applied, the result
resembles a common sweep test signal. Again, use a waveform monitor to look
at (all) the video lines to see the effects of K
X2
. When K
X
is 0.0, setting K
X2
to 9
will result in the line waveform changing from DC to 9 c/aph in the width equal
to one active picture height.
As with K
X
, the ending frequency depends on the aspect ratio of the active video
standard. For example, in a 16:9 standard with a K
X
of --9.0, a K
X2
coefficient of
9.0 causes the waveform to increase to DC in one aph. The frequency increases
to approximately 7.0 c/aph by the end of the line.
Use this formula to calculate K
X
and K
X2
terms for a sweep with the DC point at
mid-screen:
K
X
=
Ꮛ
–
1
2
R
aspect
Ꮠ
×
K
X
2
where R
aspect
is the aspect ratio (width/height) of the active video standard.
The Horizontal Sweep zone plate signal is a K
X2
-only zone plate (see Figure
C--4).
K
X2
Parameter