I do not think it works, but it might. I don't know anything about cuckoo clocks so hopefully pictures will show what you need to see! I think that the weight is jammed.
It seems to be stuck and the chain will not pull tighter. Hopefully the new owner can repair. It's large, heavy and about 17 tall. Hard to make out words but I can read Albert Schwab Karlsruhe Made In Germany engraved on the metal interior.The outside has a paper label that says Dr. Someone has written 11-13-79 in pen on 2 areas of clock. I don't know why.
Please note that the piece that has the deer head has broken wood. This can be seen in photo 11. Underside of clock has some splintering wood- please see all photos. Exact age is unknown to me.