--- title: Capacitors type: Capacitor description: This is the description image: https://placehold.co/600x400 usage: Capacitors stores an electrical charge, expressed in microFarads (μF), nanoFarads (nF) of picoFarads (pF). whereToFind: Everywhere! schematicSymbol: https://upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Types_of_capacitor.svg/460px-Types_of_capacitor.svg.png alsoKnownAs: "Caps, condenser" --- Capacitors come in all sizes. I’ve seen capacitors as big as a coffee cup, and the SMD ones are so small they are barely visible. They are passive components that can be found in most electronic circuits. There is a wide variety of types available, like ceramic capacitors, electrolytic capacitors, etc, each having their own properties. Electrolytic capacitors specifically, do not age well. Fully unused they have lifespan of 2 to 3 years. There are (complicated) ways of getting them back to life, but (@jangUnplannedObsolescenceHardware2017) recommends that they are replaced by ceramic capacitors, that have a lifespan of 100+ years. ### Salvaging Capacitors safely Capacitors store electricity, even after being disconnected from power. Accidentally touching the legs of a charged capacitor can give you a shock. Larger capacitors, such as the ones found in camera flashes or television sets, can store a dangerous amount of electricity. Make sure to always discharge the capacitors before storing them away. ### Discharging capacitors This process releases the electronic charge from the capacitor. I do this by connecting the two legs of a capacitor together using a screwdriver. This can cause a small spark, as you’ve just created a short circuit. As long as you stay away from the big capacitors in TV’s and camera flashes, this method is fine. ### Testing capacitors You can verify the capacitors capacitance with a multimeter. My multimeter doesn't have a capacitance setting, but this is not a necessity. Set the multimeter continuity mode, where it'll give a beep if there is continuity. Test a discharged capacitor by touching the legs of the capacitor with the probes of the multimeter. If there is no sound, or a continuous volume/pitch, the capacitor is dead. Otherwise, it's fine.