Does anyone know of a dating system for these clocks? I know it’s between 1943 and 1963 because of the postal zone in the address, and I estimate it’s from the ‘40s because of the cloth wires inside. If I’m not mistaken I don’t believe cloth wires were still widely used after the ‘40s. does anyone know what the knob is for under the dial? It just feels like it unscrews but there are two wires going to it inside the case.