Tv works fine for awhile then screen goes black but can still hear sound

Double check all your connections.

you may need to change the HDMI board in the tv. it will be the hole board the parts are just to small to replace them all to get the HDMI board working again. find a second hand replacement. should be fine with another known working one.

Replace the medieval TV.

I would check to see if any capacitors have gone bad or are going bad.

Hello
Hello
It is due to some loose soldering points [dry soldering we say it technically], in the power supply section of the TV. Just check for it. Check the solderings of all components, that will heat up to an extent when the TV works on. Repeated heating and cooling may make solderings to the terminals of that components to get loose. Just resolder all the suspected solder terminals, by applying a little more solder, without making any solder bridge short in between adjecent solder terminals. This must solve the problem to your tV. OK.

you have the problem in the heater section of your crt there is an open resistor.

Not good. Make sure you have not blocked cooling to TV. It need s air flow. sounds like overheating

this is the problem related to display of ur TV screen...please contact the service centre...plz dont try to repair it urself..

most likly its your lamp you just need to get a new one off the internet or you can bring it to a repair shop and they will be able to replace it for alittle bit more then the lamp itself will cost

I have a similar issue. Sometimes the entire screen goes black and sometimes only one-half - either the top or bottom half goes black. The only solution we have found is to gently tap the TV (usually the front side) and the picture will come back for awhile. It almost seems heat related as it only goes out after the first 10 minutes of use. There must be a fix to this.