Ensemble Designs 5400 Dual Sync Generator and Test Signal Generator with HD Tri-Level Sync - Manual (Page 40)

Timing Test Patterns
Timing test patterns are used to evaluate blanking area, field location, relative luma and
chroma timing, and cositing.
Analog Blanking Markers
The analog blanking markers test pattern draws a box around each field to show
the limits of blanking in composite systems. The size of the box is different for
NTSC than for PAL. In NTSC, the top of the field is at 21/284 and the bottom is at
262/525. In PAL, the top of the field is at 24/337 and the bottom is at 310/622.
The left and right markers are separated from digital blanking, which is narrower,
by a step so that actually blanking edges can be observed after passing through a
process that imposes blanking.
Digital Blanking Markers
The digital blanking markers test pattern draws a box around each field to show
the limits of blanking in digital systems. The size of the box is different for NTSC
than for PAL. In NTSC, the top of the field is at 20/283 and the bottom is at
262/525. In PAL, the top of the field is at 23/336 and the bottom is at 310/623.
The left and right markers are immediately inside EAV and SAV.
Cosite
The cosite test pattern assists in determining that the luminance and chrominance
parts of a digital signal are occurring in the appropriate relative time.
The vertical magenta pinstripe consists of a single cosite pulse in Y, Cb and Cr.
Because they are cosited and are only one sample wide, a mistiming of these com-
ponents will not appear magenta on a monitor. Cb and Cr can be determined easily
on a waveform monitor because Cb is smaller than Cr. The levels are as follows:
Y-1B7h, Cb-3C0h, Cr-340h. The pinstripe is also useful because it is in the middle
of the line.
Interlace
The interlace test pattern is helpful to show that field 1 and field 2 are occurring in
the correct relationship to each other. A horizontal field timing strip and field 1/2
markers are included.
The horizontal field timing strip can be used to show that field 1 and field 2 are
cosited in time. The middle segment of the strip, which happens during field 1,
should occur between the outer segments, which happen during field 2. If it does
not, then the relative timing is shifted or the fields are swapped or missing.
The field markers help to identify which field is which. Field 1 has a roman
numeral "I" in it, and field two a roman numeral "II". If a field is missing, as in a
frame store in field mode, one of these markers will be missing. When viewed on a
waveform monitor or oscilloscope, the fields can also be identified. The field 1
marker has chroma content while the field 2 marker does not.
Bowtie
The bowtie test pattern is used to accurately measure the chroma to luma delay in
component systems in conjunction with a waveform monitor that is designed to use
it.
Model 5400 Dual Sync Gen/Test Signal Generator
5400-A6