Rewinding bobbin

Question

trying to find a way to get a owners manual for a signature sewing machine that is very old, and I can't find any information to tell me what model it is or how old it is. It has a compartment on the top that lifts for a cam and to rewind the bobbin. It has a button on the bottom for sewing and one for embordery. It also has a spot on top for button holes. can you help me find me some information on this machine. I think the belt (on the outside and is yellow with ribs.) is causing a problem with rewinding the bobbin. The bobbin starts to rewind and it just stops like it has lost the tension on the rewinder. Thank you for your help in this matter. My e-mail address is [e-mail].