The VNA screen should be bright with all annotations and text readable. The display test allows you to check for non-functioning pixels and other problems.
Note If the display is dim or dark, refer to “Troubleshooting LCD Display Problems” in the VNA Service Guide.
A pixel is a picture element that combines to create the image on the display. They are about the size of a small pin point. Damaged pixels can be either “stuck on” or “dark.”
Stuck on pixel - red, green, or blue; always displayed regardless of the display setting. It will be visible on a dark background.
Dark pixel - always dark; displayed against a background of its own color.
Press System > Service > Diagnostics, and then click Display Test...
A multi-color screen is displayed. Be prepared to look for the symptoms described below. Click the Start Test button. To continue to the next test, click the moving Next Test button. The button moves to allow you to see all of the display. After the test is completed, the display defaults to the network analyzer screen.
One or more of the following indicate a bad display:
Complete row or column of “stuck on” or “dark” pixels
More than six “stuck on” pixels (but not more than three green)
More than twelve “dark” pixels (but not more than seven of the same color)
Two or more consecutive “stuck on” pixels or three or more consecutive “dark” pixels (but no more than one set of two consecutive dark pixels)
"Stuck on or “dark” pixels less than 6.5 mm apart (excluding consecutive pixels)
If any of these symptoms occur, your display is considered faulty. See the Service Guide for your VNA model.