Sam 5 Video Problem Isolation - Control Data Corporation CDC CC63X Hardware Maintenance Manual

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SAM 5-1
SAM 5 VIDEO PROBLEM ISOLATION
Prerequisite: To use this SAM you must be able to:
A. INITIATE resident diagnostic test 3.
B. LOCATE the alignment notches in the bezel assembly.
Assumptions: Terminal passed resident diagnostic test 1 (power
up). Resident diagnostic test 3 has been initiated and the
screen is displaying the proper test 3 message (see procedure 2).
001 Y N Alignment pattern tilted or noticeably undersize?
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002 Y N Alignment pattern does not align with notches cut in
bezel at all 4 corners? (See figure 6B-3)
003
Y N
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Y
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005
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006 I
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2 2 2 2
A B C D
62940034 E
Test 3 display jittering?
N Test 3 display rolls vertically?
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Y N
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Test 3 display rolls horizontally.
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Y N
Test 3 display characters are out of focus,
to dim, or to bright?
I I
I I
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1
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Y N
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Test 3 display has extra characters or video?
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Y N
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Did video problem appear when changing from
80/132 characters to opposite of what was
selected or when selecting 24/30 lines
opposite of what was selected.
Problem not covered. Call for assistance.
1 1
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Replace main logic board (procedure 10).
2
Replace large graphics option board (proce-
dure 9).
Adjust FOCUS potentiometer (procedure 16). If
FOCUS and BRIGHTNESS have little affect, adjust
VIDEO GAIN potentiometer per procedure 16 to
ensure it is set correctly.
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