I have a JVC RM-C1512 (think that's the model number) Ser No 11813438. Flat screen tv approx 28 inch. When turning on the bottom half of the screen is blank (black) with no picture what so ever. It does this on all channels including all AV channels. Have reset the tuning however nothing. Teletext once again only shows half the screen. Think it might be the tube that requires replacing however just wondering if there is anything else it could possible be. Item is only 3 years old.