Business band stands for a series of frequencies in the UHF and VHF two-way radio bands, which are exclusively reserved for businesses to communicate within limited ranges. Of course, not just anyone can use this bandwidth. Anyone that wants to use the business band must first receive a license from the Federal Communications Commission, also known as the FCC.
There are some exceptions to this rule in the form of five frequencies, which are part of the Multi Use Radio Service, which means the
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The Frequency-Hopping Spread Spectrum (FHSS) is a means of transmitting radio signals by shifting a carrier across a number of channels with a pseudorandom sequence that the sending and receiving station knows beforehand. The method is used as a multiple access process in the FH-CDMA (Frequency Hopping Code Division Multiple Access) transmission scheme.
What Are the Advantages of Spread-Spectrum Transmission?
The frequency hopping spread spectrum over a fixed-frequency transmission method has
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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 It was soon superseded by other transmitters due to its discontinuous radio wave production and widely varying frequencies.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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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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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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MURS, or the Multi-Use Radio Service, is a public radio service created by the FCC in the Fall of 2000 that can be accessed by any individual for personal or business-related purpose. MURS was created for the general public to use without acquiring a license to broadcast, but requires that users remain within the frequencies allotted to MURS. Officially, MURS is defined by the FCC as a “a private, two-way, short-distance voice or data communications service for personal or business activit
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MSK (Minimum Shift Keying) is a type of continuous frequency shift modulation that is used to transfer radio signals from satellites and radio broadcasting to mobile devices and vice versa. Unlike other forms of frequency modulation, MSK produces a half sine wave that limits problems associated with non-linear distortion.
What is GMSK?
GMSK (Gaussian Minimum Shift Keying) is a type of MSK that uses the same basic concepts, but applies a Gaussian filter to a signal before its frequency is m
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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, Extended-Range RFID Skimmer." The paper demonstrates just how very simple it has become to 'skim'
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A radar jammer is a piece of equipment used to scramble nearby radar signals. Radar jammers are often used by drivers to jam the signals coming out from police speed detectors. The radar jammer is very similar to the Power Drainer and is the size of a small box.
Radar Jamming as a Crime
There are active radar jammers available that work on the principle of interfering with the Doppler shift that is created in the radar beam from the radar gun. However, the law states that the interfering of po
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