Medium Earth Orbit (MEO) refers to a satellite which orbits the earth at an altitude below 22,300 miles (geostationary orbit) and above the altitude of Low Earth Orbit (LEO) satellites. Medium Earth Orbit represents a series of tradeoffs between geostationary orbit (GEO) and Low Earth Orbit (LEO). Medium Earth Orbit enables a satellite provider to …
Trickle charging, also called float charging, is the replacement of charge lost through self-discharge. Trickle chargers work at a lower rate than quick chargers, and are used to keep a battery at full charge, not to charge it from empty. Some battery chargers use electronics to control both quick and trickle charge modes, allowing them …
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 …
The broad definition of a transducer is a device that changes energy from one type into another. However, most transducers change between electricity and another energy type. Transducers also have other names depending on their usage such as probe, detector, pickup, sensor, gauge, and electrode. Chemical Transducers Acidity and alkalinity are measured using a pH …
An LNB (Low Noise Block aka LNC- Low Noise Converter) is used for communications (broadcast) satellite reception. The LNB is usually affixed either in or on the satellite dish. The LNB’s purpose is to utilize the super heterodyne effect and amplify and convert a wide block (band) of frequencies. This helps compensate the signal loss …
SCPC stands for Single Channel Per Carrier. SCPC is a form of satellite transmission where each channel is transmitted on a dedicated single carrier. The alternative to SCPC is MCPC (Multiple Channel Per Carrier). MCPC is more efficient than SCPC, but SCPC is still utilized for some satellite feeds. By using SCPC, satellite users are …
DVB-RCS stands for Digital Video Broadcast – Return Channel Satellite. DVB-RCS is part of the DVB standards for satellite communication, DVB-S and DVB-S2. The purpose of DVB-RCS is to provide a return channel to enable Internet and other data services over satellite. ViaSat’s LinkStar system is one of the VSAT satellite broadband implementations which support …
The symbol rate is the rate of state changes on a communications circuit. If a circuit can carry two tones per second, the circuit has a symbol rate of two. Circuits then use different modulation techniques to carry multiple bits per symbol. If the circuit is limited to two different tones, the first tone can …
A piezoelectric transducer is a device that converts electricity into mechanical forces or vibrations. Although piezoelectric transducers have other uses, ultrasonic devices require them. Piezoelectric transducers usually converts electricity into vibrations and vibrations into electricity, although this is not always the case. They rely on two phenomena known as “electrostriction” and “the piezoelectric effect.” How …
A projector lamp is used to transfer an image from a multimedia projector onto a larger screen. Earlier halogen bulbs were used for many years for projection purposes, but were discontinued as halogen produced a yellow tone on the images. A projector lamp relies on an intense light bulb, called a metal halide bulb, to …