4-18 Service Guide N5230-90014
Troubleshooting PNA Series Microwave Network Analyzers
Front Panel Troubleshooting N5230A
Checking the RPG (Front Panel Knob)
To check the RPG knob, rotate the knob and check for a fluid movement of numbers in the
Velocity box.
• If the movement of numbers in the
Velocity box is not smooth or no numbers appear at
all, suspect a faulty A3 front panel interface board. To replace the A3 front panel
interface board, refer to “Removing the A3 Front Panel Interface Board” on page 7-10.
A2 Display Test
The display 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” on page 4-12.
What Is a Damaged Pixel?
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.”
• A “stuck on” pixel is red, green, or blue and is always displayed regardless of the display
setting. It will be visible on a dark background.
• A “dark” pixel is always dark and will be displayed against a background of its own
color.
How to Run the Display Test
To run the display test, perform the following:
On the
System menu, point to Service, and then click Display Test.
A multi-color screen is displayed. Be prepared to look for the symptoms described in “How
to Identify a Faulty Display,” and then 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.
How to Identify a Faulty Display
One or more of the following symptoms indicate a faulty A2 display assembly:
• a 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, replace the A2 display assembly. Refer to “Removing the
A2 Display Assembly” on page 7-10.
To Next Page
Loading...
