I have one very similar. I have a hard copy of the manual, not online though. I could photo copy or scan it for you if you do not find a soft copy of one.
I tried this unit out, and it seems to be inoperative. I opened it up and there are some components that have been unfastened from their mounting. It also has a tube that looks burnt. It will certainly take someone with a strong electronics background to trouble shoot this one…. I think this will go into the "later" shelf.