Quantum Data 801GC, 801GF, 801GX Owner's And Programmer's Manual page 49

BriteBox — contd.
Test
Purpose
Method
Brightness uniformity
The light output of most picture tubes varies
slightly when measured across the CRT face. This
test can be used to verify that the light output
variation is within your spec limits.
S e l e c t t h e i n v e r t e d v e r s i o n a n d p e r f o r m t h e
Brightness Control Adjustment test on the center
box. Then center the light meter probe in each of
the corner squares and note the reading you get
for each square. The deviation between each of
the corner readings and the center reading should
be within your spec limits.
4-11