I've got no power

This could be something as simple as a bad power cord. Checking with a DVM will confirm or rule it out.

Anything else will require disassembly and there are no service manuals available to help.

If you can figure out how to open it up, the next simple fix would be a fuse. Again it is an eyeball thing and a DVM verify. If it is a fuse, it might be just that or more likely something else caused it to blow. The next item is the power switch. Again, verify with DVM. Past that you need to be a little more technical to figure this out, or have someone put their hands and eyeballs on it. At $39.99 new, it will cost more to get it fixed. A new one will have some warranty. A fix won’t.