Hi All --- I'm a newbie to the forum, and a newbie to the idea of fixing my beloved boombox but an oldie in terms of audio interest. Used to DJ weddings, high-school dances, small-town radio, etc etc.

So where does one start? I'm game to rip it open and root around, but I thought I'd ask for general advice first/specific advice on what I'm looking for in terms of the blown channel. 

Also, needs a new antenna. I'm guessing this'll be easier to deal with...

as You have mentioned - this has been used a lot  

Start with Cleaning you Switch's Slider's & Potentiometer's - as you may discover your lost channel behind some dirt in your input device's

( long time ago I fixed one boombox with no sound by simply cleaning the headphone jack - as the little switch inside was stuck open preventing the onboard Loudspeaker's to operate )   Then if No sound after all of that then you need to take it to a technician unless you know your way around electronics  

  Once inside you may look for burnt item's that may be defective cause they are burnt

Lastly picture's uploaded to here to show your progress is the greatest help you can give yourself to the Other's here to give a better understanding of just what you are doing