An IR blaster (infrared blaster) is a device that emulates an infrared remote control. IR blasters are used in situations where one device controls another. For example, it can be connected to a computer in order to control virtually every other infrared device in the room from that computer. IR blasters are usually small and …
Radio-Frequency Identifier (RFID) technology has become really popular because of the various advantages it comes with. However, such as passports, national identity cards, credit cards etc have become a serious security concern. Two electrical engineering students (Ilan Kirschenbaum and Avishai Wool) from Tel Aviv University wrote a paper titled "How to Build a Low-Cost, …
Low Earth Orbit (LEO) refers to a satellite which orbits the earth at altitudes between (very roughly) 200 miles and 930 miles. Low Earth Orbit satellites must travel very quickly to resist the pull of gravity — approximately 17,000 miles per hour. Because of this, Lowe Earth Orbit satellies can orbit the planet in as …
Resistors can come in different sizes and shapes allowing for different voltages to go through it. However, unless the size of the resistor is large, the code is rarely written on it because it would require very tiny markings. Therefore, a system was developed to use colors to determine the resistor code. In other words, …
A high-frequency alternator is an electrical device used for radio communications. It yields high-frequency, periodically alternating current that can go as high as 100,000 Hz for the purpose of producing stable radio waves. The History of High-Frequency Alternators By the first decade of the 20th century, wireless telegraphy was already in place and was no …
Some materials have the ability to produce electricity when subjected to mechanical stress. This is called the piezoelectric effect. This stress can be caused by hitting or twisting the material just enough to deform its crystal lattice without fracturing it. The effect also works in the opposite way, with the material deforming slightly when a …
A Capacitor Bank is a group of several capacitors of the same rating that are connected in series or parallel with each other to store electrical energy . The resulting bank is then used to counteract or correct a power factor lag or phase shift in an alternating current (AC) power supply. They can also be …
Geostationary satellites are located exactly above the earth’s equator and revolve around the earth in a circular orbit. Their revolving speed and direction (west to east) are exactly same as that of the earth, which makes it look stationary from the earth’s surface. The exact altitude of these satellites above the equator is approximately 36,000 …
Forward Error Correction (FEC) is a type of error correction that involves encoding a message in a redundant way, which allows the receiver to reconstruct lost bits without the need for retransmission. How Forward Error Correction Works FEC works by adding “check bits” to the outgoing data stream. Adding more check bits reduces the amount …
Uplink refers to a transmission of data in which data flows from a ground-based transmitter to an orbital satellite receiver. Uplink is used to send data to a satellite in Earth’s orbit in order to make changes to the way the satellite functions or simply redirect data to another ground-based receiver. Uplink is used in …