My 1980's cocktail version of Ms. Pacman was working just fine, then the screen went blank and now all it does when I turn it on is make a hideous noise like an electronic elephant dying (I imagine). What is strange is if I have it open and press the interlock switch, that’s when I get power and the noise starts. When the unit is closed and I turn it on, I get nothing. Any thoughts would be appreciated. I have a feeling this will take an expert to work on it, just trying to find one in the Gettysburg/Thurmont area is tough.