A heterodyne is a circuit that transfers a signal from one carrier wave to another with a different frequency. It mixes the input signal with a wave generated by an oscillator to create two new signals, called beats. While heterodyning is a simple process governed by the laws of trigonometry, most heterodynes are complex devices with several filters and amplifiers.
Heterodyne Beats
A beat is a signal produced by two input signals with different frequencies. A heterodyne produces two beats, o
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A spark-gap transmitter is a mechanism for producing radio signals. It has been the primary radio transmission device during the early years of radio technology. It was soon superseded by other transmitters due to its discontinuous radio wave production and widely varying frequencies.
How a Spark-Grap Transmitter Works
A spark gap transmitter is basically composed of two capacitors (electrical apparatus designed to store electrical energy). However, the switch that ultimately forms the connect
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Plastic electronics is an offshoot of electronics which focuses on devices made from conductive plastics - otherwise known as organic polymers - rather than silicon.
Manufacturing Plastic Electronics
The "heart" of modern electronics are microchips - circuits and wiring "diagrams" are designed and micro-miniaturized to the point that thousands or even millions of circuits are contained in a one-inch square chip which is "burned" (or etched) onto ultra-thin inorgan
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8PSK (8 Phase Shift Keying) is a phase modulation algorithm.
Phase modulation is a version of frequency modulation where the phase of the carrier wave is modulated to encode bits of digital information in each phase change.
The "PSK" in 8PSK refers to the use of Phased Shift Keying. Phased Shift Keying is a form of phase modulation which is accomplished by the use of a discrete number of states. 8PSK refers to PSK with 8 sates. With half that number of states, you will have QPSK. With twic
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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 cover the earth with fewer satellites than Low Earth Orbit, but requires more satellites to do so that geostationary orbit.
Medium Earth Orbi
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FRS (Family Radio Service) is an unlicensed service.
FRS (Family Radio Service) consists of 14 UHF channels on FM. FRS Channel 1 is unofficially used as a common call channel.
FRS (Family Radio Service) shares channels 1 through 7 with GMRS, and many FRS radios are also GMRS radios.
The maximum allowable power for a FRS (Family Radio Service) radio is .5 watts. GMRS radios are allowed to transmit on the channels they share with FRS at 5 watts, ten times the power of FRS radios.
Unlike GMRS
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MIL-C-5015, now known popularly as MS connectors, are multi-pin, highly durable connectors that were originally invented for use in military applications. They have a variety of features that makes them easy to use for nearly any application and are often found in a variety of advanced, high power, heavy duty devices in the industrial world.
MS connectors are a type of circular threading connector that requires no tools to assemble. Installation can be done by simply the barrel into the recepta
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Real-time locating system, otherwise known as RTLS, is a technology that is interconnected with GPS. An individual can attach a receiver to something they are shipping and then, at any given time, know the exact location of that item anywhere in the world due to the RTLS technology. In other words, RTLS allows for shipping companies to keep a consistent track on their shipments so they can offer clients a more detailed delivery expectance time. While it is still newer technology, RTLS is quickly
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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 associated with typical coaxial cable at relatively high frequencies.
The term 'low noise' relates to the quality of the 1st stage input amplifier transistor,
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XM Radio is a satellite radio service. Satellite radio is a technology that for the most part has been around for many years. For instance, many television studios have been using satellites to beam TV signals from far away locations to viewers for decades, however satellite radio has been in operation in America since 2001.
Satellite radio is pretty easy to describe. The programs for satellite radio include music, talk shows, live sporting events and sport analysis shows. These shows are usual
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