A TechLore "Ask the Experts" Question...

Question:

I have an RCA XL100 TV. I'm getting green fringing around bright white areas of picture, and was told that it picture tube is tired. It seems strange becaues if the picture has little white, there is no problem. It otherwise looks good. I don't believe this has to do with convergence.

-submitted by Sparks

Answer:

What you were told makes sense based on the information you provided, the picture tube could be reaching the end of it's usable life.

White is the most intense color for a television to produce since all three colors are driven to maximum intensity to produce it. Tubes that are getting on the older side often do just fine when producing less intense primary colors, but bloom or defocus when driven harder.

One thing you could try is reduce the maximum white level of the TV by reducing the contrast (picture) control. Check out the article How To Use Your Television's Video Controls for more information about how to do this.

Depending on the age of the set, you may have to reduce it substantially to get past this problem, but it should suffice until you can replace the TV. In order to truly repair the TV, the picture tube will need to be replaced, which would be way more expensive than it's worth. Check out our article How To Determine If You Should Repair a Broken Device to help you make a well informed repair decision.

Matt Whitlock - Editor, TechLore.com