we think we deciphered the model of this electrical switch as a Trumbull-Vanderpoel Electric Manufacturing Company single throw, double pull, fused at the bottom knife switch. Electrical Record. Based ...

Wrap the 4-inch nail with a coil of 25 to 50 turns of the wire. Connect one end of the coil to one terminal of the knife switch. Connect the other terminal of the knife switch to the battery.