IBM 5155 Manual To Operations page 188

31
Turn the Contrast control fully clockwise. Look
at the following examples.
Too Dim
Too Wide Too Narrow
I I
Out of Focus Shrunken Characters shifted left
or right or up and
down off the display
area
Tilted
32
Is the problem similar to one of the examples?
YES - Have your display serviced.
NO - Go to "Diagnostic Testing" on page
Test 000-1 earlier in this section.
9000-12 Test January 1984