802BT/802R Video Test Generator User Guide 651
Test Convergence adjustment (color monitors only)
Purpose To accurately produce an image on a color monitor, the three electron beams in the CRT
must meet (converge) at the same location at the same time. Lines displayed on a
misconverged monitor appear as several multi-colored lines, and the transitions between
different colored areas contain fringes of other colors.
Method The convergence adjustments of most color monitors fall into two main cate gories. The
first set of adjustments, usually called Static Convergence, aligns the three beams in the
center of the display. This method involves turning on all three guns and adjusting the
various magnets on the convergence assembly to produce all white dots in the center of
the display. The convergence assembly is located on the neck of the CRT. Different
monitors and CRT types may each require their own magnet adjustment sequence.
After the center of the display is properly converged, the outer areas are adjusted by using
the monitor’s Dynamic Convergence controls. The number of controls, the area of the
screen they affect, and their adjustment procedure depend on the monitor under test.
Hatch_16, Hatch_20Description The primary version of the Hatch_16 image is shown below. The secondary versions draw
black lines on a white background.
1 : 1 1.000 10 10 12 12 24 24
3 : 4 0.750 14 10 16 12 32 24
Aspect Ratio Dot_10 Dot_12 Dot_24