Welcome to the forum,
A) Take it to a knowledgeable and responsible electronics expert - set aside $100-200, shouldn't be more
B) Spend $100 on an oscilloscope and soldering iron - set aside all of your free time for a while.
There's probably a good person to take it to in your area, and it's probably a simple blown capacitor some such thing. If you want help finding a good repairman, let us know your location, and perhaps someone here can recommend someone.