1. The problem statement, all variables and given/known data Hi all, My question is: In what kind of device the enclosed schematic can find an application? The bipolar switch has two positions U and u- which are for upper position and D and d- which are for down position. The main question is on what kind of equation the voltage on capacitor Cv is depending. Schematic 2. The attempt at a solution My attempt was quite a success I've measured the voltage on Cv with the voltmeter while moving the key from upper to down position, as said in the question. It was equal to e (the small battery -1,5V) no matter from what is the E (the 3 cell battery on the schematic). So the simple solution is: When the switch is switched to down position: The capacitor Ch is charged to E. When the switch is switched to upper position: The capacitors Ch and Cv are in series, also E and e are in series. So Voltage on cv will be = E+e-Vch=E+e-E=e=1,5V. MY PROBLEM IS WHERE THIS CIRCUIT CAN FIND AN APPLICATION?