Just because it's old doesn't mean it's not usable equipment. If it were me, I'd run through all of it and just make sure that the wiring isn't frayed or damaged in some respect. Once you've done that, just make sure all the connections are solid. Some may be corroded so take those apart, clean them and put them back together. Once you get done with that....plug it in to a GFCI outlet. If it's bad, it'll trip the outlet and all is good. Then you'll know whether you can use it or toss it (better yet...sell it to Andyman! LOL) How about some pics....that will help us.