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Main => Monitor/Video Forum => Topic started by: grantspain on February 23, 2006, 08:31:31 am

Title: rptv tube burn
Post by: grantspain on February 23, 2006, 08:31:31 am
Does anyone know if there is a way of reducing burn on tubes,my friend has a rptv from a sega rally that he uses as a tv,unfortunately there is some burn on the tubes so you can see game over etc.Now i do remember many years ago a tv engineer told me there was a way of reducing this but i cant remember,otherwise he will have to purchase 3 new tubes and i am told that this could cost up to 800 pounds per tube which seems very costly :'(.If anyone has any advice it would be gratefully recieved.
Title: Re: rptv tube burn
Post by: menace on February 23, 2006, 11:07:27 am
i've heard if you run the negative image for the same amount of time it will reduce the entire tube to the same level of burn--i.e. white letters black background--would go to black letters white background--keep in mind i have never seen this done or known anyone personally who did this--more of a wives tale courtesy of the internet  :D
Title: Re: rptv tube burn
Post by: D_Zoot on February 23, 2006, 11:14:56 am
Nope, there is no real way of reducing burn in any CRT based set.

There have been attempts to reduce the effects of the burn in projection sets by running a reversed image of the burn.  These attempts have met with limited results.  The theory goes that by running a reversed, still image on the screen will even out the phosphor wear thus minimizing the effects of burn.  In reality it's nearly impossible to do this as running an inverted picture requires video generation equipment and perfect layout and alignment of the inverted video. If the inverted image isn't perfectly aligned with the burn, because of geometry changes in the set from movement, failing caps, etc..   then the burn will still be visible.   It's also impossible to to determine how long to run the image and at what brighness to even out the phosphor wear.  Besides, burning the remaining phosphors to minimize the effects isn't really fixing anything.

D

Title: Re: rptv tube burn
Post by: menace on February 23, 2006, 12:35:08 pm
sure go ahead, ruin a perfectly good wives tale :P suppose you are going to tell me that standing on my head drinking water won't cure the hiccups!   :laugh:
Title: Re: rptv tube burn
Post by: censei on February 23, 2006, 01:04:45 pm
having a good level of screen/brightness can make burn in on crt's sort of less noticable. This is what I've seen over the decade.