how can i fix my matsui 10" portable tv it has sound but just a thin coloured line down the center of the screen and where can i get a circuit repair manual or diagram from
You could try DSG (aka Dixons) as Matsui is one ot their brands. I assume that you are not a novice as the inside of a TV set is extremely dangerous with potentially lethal voltages present - even when the set is swtched off and unplugged from the mains.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix televisions.