The author wants to present an uncommon description of an energy transfer process in core-collapse supernovae: namely, a gravitational machine that increases Coulomb energy within nuclei via silicon burning. Excess of that Coulomb energy is returned weeks and months later by weak nuclear decays (EC and beta+). Those decays energize several observable quantities: gamma-ray lines, X-ray luminosity, free chemical energy and optical light curves. The delay of the energy return is essential for visibility of these activations. These secondary displays have rich literatures; but expressing them as observables of a supernova machine, whose action can be summarized as gravitational compression→Coulomb nuclear energy increase→release of excess of that Coulomb nuclear energy by electroweak decays→supernova displays, is novel.