Vacuum Tube Curve Tracer

Every day we throw away tons of supposedly empty 1.5-volt alkaline (“dry”) cells. Triggered by the waste caused by my battery-powered equipment failing to work with partially discharged cells, I designed a circuit to step up the voltage of one exhausted cell to around 5 V for use in another application. Say, to make an LED light, keep a lightweight microcontroller buzzing, or power remote sensors that do not demand much energy... Until that battery, like The Parrot, is dead.