Tv plays then picture goes out but still have sound

Plasma TV Repair Tutorial Common Symptoms Solutions How to Fix Plasma TVs

Looks like a problem with mother board. Call LG and they will replace the mother board in around Rs 7000/-

Sounds like a hard drive failure. Contact Dish Network for warranty/repair info.

Take it in to a service center for an Estimate. Parts are very difficult for Westinghouse sets.

i have had this problem on one of my tv s all i did was remove the back of the tv and re-solder all the joints around the tuner (thats where the arieal goes) they go with time because the joints there get so hot . hope this helps
puggy

Is it ok when you watch regular TV thru the cable or sat?

resolder the vertical output IC . bad solder there can make the CRTs blank for protection and you will lose the picture when the vertical drops out.

Convergance IC replace.
http://home.earthlink.net/~oleg.filippov/ConvergenceFix.htm