2985 dx not turning on when switch is turned on

[airplane1]

Any one know What would cause this radio to not turn on when switching it on?

One day it worked the next not, I hear the power supply humming very slightly like it always did so I think the power supply works. No lights, sounds nothing. total dead.

Is there a way to test it or like what should I look for?

Any help out there?

Thanks,
airplane

 

[Moleculo]

Did you hook up the power backwards?