<< radio home
<< index
by disinfoniacs #69 & #1
>>>>
Resistors are electronic components that limit the flow of electric current in a circuit. They are usually made of a material that resists the flow of electricity, such as carbon or metal. The resistance of a resistor is measured in ohms (Ω). Resistors are often used to control the brightness of LEDs or the speed of motors.
Potentiometers are variable resistors that can be adjusted to control the amount of current flowing through a circuit. They have three terminals - one for the input voltage, one for the output voltage, and one for the adjustable tap. By turning the knob on the potentiometer, you can vary the amount of resistance and hence the amount of current flowing through the circuit.
Capacitors are electronic components that store electric charge. They consist of two conductive plates separated by an insulating material called a dielectric. When a voltage is applied across the plates, they store a charge that can be released later. Capacitors are often used to smooth out voltage fluctuations or to filter out high-frequency noise.
Inductors are electronic components that store energy in a magnetic field. They consist of a coil of wire that generates a magnetic field when a current flows through it. When the current is switched off, the magnetic field collapses and generates a voltage that opposes the original current. Inductors are often used in electronic filters and power supplies.
Switches are electronic components that open or close a circuit. They can be mechanical, such as a push-button switch, or electronic, such as a transistor switch. Switches are used to turn on and off electronic devices or to select between different inputs or outputs.
Relays are electronically controlled switches that use an electromagnetic coil to switch a high-voltage or high-current circuit. They consist of a coil that generates a magnetic field when a current flows through it, and a set of contacts that open or close when the magnetic field is present. Relays are often used to control large electrical loads, such as motors or heaters.
Fuses are safety devices that protect electronic circuits from overcurrent. They consist of a wire or filament that melts when the current exceeds a certain threshold, breaking the circuit and preventing further damage. Fuses are often used in power supplies or motor control circuits.
Meters are electronic devices that measure various electrical properties, such as voltage, current, or resistance. They usually have a digital or analog display that shows the measured value. Meters are used to diagnose faults in electronic circuits or to calibrate electronic equipment.
A diode is an electronic component that allows electric current to flow in only one direction. It consists of a semiconductor material, typically made of silicon or germanium, that has a p-n junction. A p-n junction is a boundary between two types of semiconductor material - p-type, which has positively charged holes, and n-type, which has negatively charged electrons. When a voltage is applied to a diode, the p-n junction allows current to flow in one direction, but blocks it in the opposite direction.
Diodes have two terminals - the anode and the cathode. The anode is the positive terminal, and the cathode is the negative terminal. When a diode is forward biased, meaning that the anode is at a higher voltage than the cathode, current flows through the diode. When the diode is reverse biased, meaning that the cathode is at a higher voltage than the anode, current does not flow.
Many diodes have a stripe on one of their leads to indicate which end is the cathode. The stripe is often a different color or shape from the rest of the lead. It's important to note that not all diodes have a stripe, so it's important to check the data sheet or markings on the diode to determine which end is the cathode.
Light Emitting Diodes (LEDs) are a type of diode that emits light when current flows through it in the forward direction. The principle of operation is similar to that of a standard diode, with a p-n junction that allows current to flow in one direction but not the other. When current flows through the diode, energy is released in the form of light, resulting in the LED emitting a specific color. LEDs are commonly used in electronic devices for status indicators, displays, and lighting.
An integrated circuit (IC) is a complex electronic circuit that combines multiple components onto a single piece of semiconductor material. The components are typically transistors, resistors, capacitors, and diodes, and they are connected together to create a specific function, such as a microprocessor or a memory chip. ICs are essential in modern electronics and are used in everything from smartphones to cars.
A tuned circuit is a simple circuit that consists of an inductor and a capacitor connected in series or parallel. The inductor and capacitor work together to create a resonant frequency, which is the frequency at which the circuit has the highest impedance. Tuned circuits are used in electronic filters to select or reject specific frequencies. For example, a radio receiver uses a tuned circuit to select the frequency of the desired radio station while rejecting unwanted frequencies.
In summary, electronics is all about combining different components to create a specific function. Integrated circuits combine multiple components onto a single piece of semiconductor material, while tuned circuits use an inductor and capacitor to create a resonant frequency for filtering specific frequencies. Understanding these concepts is essential in electronics, as they are used in many different circuits and applications.
<< previous lesson | next lesson >>
---
<< radio home
<< index