Tektronix 1760 - Manual (Page 120)

Basic Measurements
1760 Series Component Waveform/Vector Monitor User Manual
4-20
NOTE
A valid GBR signal is guaranteed if the signal is
within the Diamond graticule. However, this does
not guarantee that the signal will be within ap-
propriate composite limits if encoded into compos-
ite NTSC.
Signals outside the diamonds are subject to repro-
ductive errors in any format.
The graticule is labeled with G, B, and R to determine the
color problem in a GBR sense. A bright excursion outside
the graticule indicates an invalid signal, subject to clipping or
inconsistent reproductions. An already clipped or limited
signal is indicated by a bright line along or parallel to the
Diamond graticule.
All colored areas (the bigger the area, the brighter the dot)
are represented by data in both top and bottom diamonds. A
perfectly monochrome signal would produce a vertical line
with luminance proportional to the vertical deflection in-
creasing upwards in the top diamond and downwards in the
bottom diamond. Increasing color saturation is indicated by
increasing horizontal deflection around the appropriate lumi-
nance value (vertical deflection) in the top, bottom, or both
diamonds.
In computer graphics and film-to-tape applications, the Dia-
mond display can be used to check for gamut limit errors
anywhere the signal might be adjusted to create improper
GBR signals. The Diamond display monitors the actual elec-
trical signal, indicating faults in the transcoding hardware as
well as operator artistic violations.