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Main => Monitor/Video Forum => Topic started by: crashwg on August 22, 2011, 09:40:27 pm

Title: Bright things cause dark band across screen
Post by: crashwg on August 22, 2011, 09:40:27 pm

I've got this TV that might end up in an arcade machine if I can fix this little issue.  The problem is on mostly dark screens where there is bright spots like words or other bright objects.  When there is such a bright thing on the screen it is always accompanied by a band of darkness that is the same height as the bright thing and spans from left to right.  I'm not sure if my description is clear enough so here's a M$ Paint depiction.  What's the fix oh great monitor gurus?

Title: Re: Bright things cause dark band across screen
Post by: lilshawn on August 23, 2011, 07:39:32 pm

you might have an issue with the B+ being a little low....

but more likely you have a capacitor in around the flyback that is getting weak.

the power used to drive the picture from black to white needs to be nice and steady and not vary. if it varies, the you get a weird banding or sometimes in extreme cases you get a screen that starts to collapse in on itself (get smaller) when it gets bright. usually it's a failing capacitor but could be a B+ going all over the place.