Electrostatic Puck: Making An Electret

You might have heard of electrets being used in microphones, but do you know what it is? Electrets produce a semi-permanent static electric field, similar to a magnet produces a magnetic field. The…

Low-Cost Electret Microphone Preamplifiers

Before the invention of microelectromechanical system (MEMS) microphones, almost all microphones in cell phones and other electronics were a type of condenser microphone called the electret microph…