Quantum Data 881, User Manual

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572 Appendix B Image Reference
Note: When outputting digital video, 33% Gray changes to 50% Gray, and 67% Gray
becomes either Black or some gray level depending on how the display interprets the video
information.
Test Verify that all video channels are functional
Purpose To verify that none of the video channels are bad or connected incorrectly.
Method Compare the sequence of color bars with the table. Missing bars may indicate a dead or
unconnected channel. The transition between the bars should be sharp and distinct. Each
bar should also be uniform in color and intensity across its entire width. Non-uniformity
may indicate problems with the response of the video amplifiers. If all the bars are present
but in the wrong order, one or more inputs may be swapped.