My crazy HP 15c repair

[Jim Horn]

There have been several posts in the past (Google "HP 15c spring") about the springs which, when the calculator is lying down, extend vertically between the front and back metal plates. They provide an electrical connection between them so that any electrostatic discharge when using it can travel from front to back and out, bypassing the electronics. Look for two small holes in the plastic front and back that let you see the inside side of the metal plate. Those are where the springs should go.

Best to you and your '15!