A varactor diode, also called varicap, VVC (voltage-variable capacitance, or tuning diode, is a type of semiconductor diode which features a variable voltage-dependent capacitance on its p-n junction when the device is reversed biased. Reverse bias basically means when the diode is subjected to an opposite voltage, meaning a positive voltage at the cathode, and […]
Work
How Transformers Work
According to the definition given in Wikipedia an electrical transformer is a stationary equipment that exchanges electrical power across a couple of closely wound coils, through magnetic induction. A constantly altering current in one winding of the transformer generates a varying magnetic flux, which, consequently, induces a varying electromotive force over a second coil built […]
How Crank Flashlights Work
A crank flashlight basically works by hand cranking a permanent magnet motor, which generates electricity for illuminating the attached LEDs. Motor Becomes a Generator Normally, a permanent magnet motor is used for executing a rotational movement by applying a DC potential across its specified supply terminals. However we also know that the same motor can […]
How Electret Microphones Work – Full Tutorial and Diagram
In this post I have explained how electret microphone devices work, through appropriate diagrams and formulas. What’s a Microphone A microphone is a device designed for transforming weak sound vibrations into tiny electrical pulses, which can be then amplified through a power amplifier over a loudspeaker for achieving a louder reproduction of the sound. The […]
How Laser Microphones or Laser Bugs Work
A laser microphone is a security monitoring gadget in which a laser beam is used for detecting audio vibrations across faraway targets, which are normally walls or glass of homes or offices. These devices could be applied for eavesdropping with virtually no chance of getting identified or cover getting blown. Laser eavesdropping gadgets, it is […]
Fuel Cells [How they Work]
Fuel cells have the capacity to be the most effective and ecologically friendly power source ever devised. Since fuel cells are able to generate drinking water as a by-product, they are indeed an appealing replacement for traditional power generation. How much more could you want from a source of energy? History Sir William Grove developed […]





