Audio Systems: car radio wont turn on, pioneer radio, delta 88

Question
Hi, I have a Pioneer radio in my 1983 Olds Delta 88. Up to a week ago, it turned on.  Then, one day I pressed the source button to turn it on and nothing happened.  I checked the fuse and it's O.K.  I pulled it out to check the wires in back, and they seem to be all right. I'm trying to figure out how to check to see if it's getting power. I think the black wire is the power wire. So, I guess is if it's not the car power line, it must be in the radio itself?  How can I check that?   Thanks for your time and considertion,    Ed Parauka

Answer
first, you're going to need a voltmeter. on olds, i think black is hot, but with a meter with very sharpened points so you can probe through the insulation and verify. if you don't find voltage, you probably have a 'fusible link' burned somewhere between the radio and the battery.(what fun) links are like fuses, it is a special type and size wire that is designed to burn that you can get from any
auto parts store. you have to replace them with the same type to avoid a fire. if you do find voltage, it is then something internal, needing repair by a tech.