Used P A Day!

I finally won my month long battle against the useless prick who took over the practice rooms I used to use and got my stuff back.

Anyone know anything about these? I'm about to give it a good clean and check everything out. Unfortunatley I don't have speakers so I can't check it still works which is kinda annoying but I'll just have to be patient I guess..
My band
PBT Native: Resident Graphics Monkey

You might be able to stick a speaker cable (or whatever PA's take) and read the tip of the cable with a multimeter. That would be one place to start. Just don't plug something stupid in there and blow a component because something doesn't match up.