In this case I bring a faille which is very common, rather two failures, and perhaps for experienced technicians is very simple but for those just beginning or have perhaps not as simple entertainment electronics. The failure screen dull but with audio, or dark screen black and with audio. Jorge Perez often expresses his thoughts on the topic. This faya occurs for the following reason, one of them is the lack of supply voltage to the CRT that is voltage measured in AC and leaving the flyback of the connector called Heter. It may the voltage does not come for several reason one of them is a resistance that is between the leg heter Flyback or directly the flyback in poor condition or that the burnt CRT is worse. In all the main forms is to have the tester and start the measurements from the flyback Asia tube. The second failure is similar and is when the trc this dark but can see the image. This can be for several reasons and one of them is exhausted tube which is not lit enough to lighten the image. Ranging from sub prest brightness and not having improved the escrim climbs and there result, one way to solve this problem but unorthodox is giving one or two wraps of rope on the nucleus of the Flyback transformer and plug directly into the feeding tube. This what does is increase the supply voltage to the tube and therefore increases the brightness but carries the inconvenience that decreases the time of duration of the CRT and if the laps that you want to put there are many immediate destruction of the tube filament can bring rigged, must be very careful when performing this type of repair. More suitable would be the change of cathode ray with a new tube but sometimes the cost is not merits by which a more immediate solution is the above-mentioned. I hope find it it useful and welcome your comments.