I have a Missile Command upright. The problem I am having is I get no sound (no beep or tones) and have a yellow raster (no video). I have checked the power supply and it seems to be working fine. I have removed the IC’s from their sockets and cleaned then reinstalled them. Still I have the yellow raster and no sound. I checked grounds and they seem fine. Can anyone help with this? I have some test equipment if it is needed to troubleshoot. Is a board replacement the way to go?? Any help will be greatly appreciated.