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ICOM IC-705
The ICOM IC-705 is a multimode HF/VHF/UHF portable amateur radio transceiver. The radio has 5 watts of output when using its internal battery and 10 watts of output when using external power. With the rise in award programs such as Summits on the Air, and Parks on the Air this lightweight fully functional radio is a popular choice for people using them in the field. The IC-705 has support for a wide variety of commonly used amateur radio modes including ICOM's proprietary digital voice mode D-STAR. The IC-705 is also one of the first mainstream amateur radios to use SDR technology instead of the older superheterodyne design. Additionally the IC-705 has multiple extra features that are useful when operating in the field. Supporting the radio's D-STAR module is a GPS receiver to allow users to send their location though the D-STAR network as well as help locate nearby repeater systems. In addition to the GPS receiver the radio supports 2.4 GHz Wi-Fi which allows users to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software-defined Radio
Software-defined radio (SDR) is a radio communication system where components that have been traditionally implemented in analog hardware (e.g. mixers, filters, amplifiers, modulators/ demodulators, detectors, etc.) are instead implemented by means of software on a personal computer or embedded system. While the concept of SDR is not new, the rapidly evolving capabilities of digital electronics render practical many processes which were once only theoretically possible. A basic SDR system may consist of a personal computer equipped with a sound card, or other analog-to-digital converter, preceded by some form of RF front end. Significant amounts of signal processing are handed over to the general-purpose processor, rather than being done in special-purpose hardware ( electronic circuits). Such a design produces a radio which can receive and transmit widely different radio protocols (sometimes referred to as waveforms) based solely on the software used. Software radios hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenna Tuner
An antenna tuner (and any of the names in the list below) is a device that is inserted between a radio transmitter and its antenna; when placed close by the antenna and properly adjusted (tuned) it optimizes power transfer by matching the impedance of the radio to the impedance of the end of the feedline connecting the antenna to the transmitter. Various alternate names are used for this device: antenna matching unit, impedance matching unit, matchbox, matching network, transmatch, antenna match, antenna tuning unit (ATU), antenna coupler, feedline coupler. English language technical jargon makes no distinction between the terms. Antenna tuners are particularly important for use with transmitters. Transmitters are typically designed to feed power into a reactance-free, resistive load of a specific value: Radio transmitters built after the 1950s are almost all designed for 50 Ω (Ohm) cabling. However the impedance of any antenna normally varies, depending on freq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winlink
Winlink, or formally, Winlink Global Radio Email (registered US Service Mark), also known as the Winlink 2000 Network, is a worldwide radio messaging system that uses amateur-band radio frequencies and government frequencies to provide radio interconnection services that include email with attachments, position reporting, weather bulletins, emergency and relief communications, and message relay. The system is built and administered by volunteers and is financially supported by the Amateur Radio Safety Foundation. Network Winlink networking started by providing interconnection services for amateur radio (also known as ham radio). It is well known for its central role in emergency and contingency communications worldwide. The system used to employ multiple central message servers around the world for redundancy, but in 2017–2018 upgraded to Amazon Web Services that provides a geographically-redundant cluster of virtual servers with dynamic load balancers and global content- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PSK31
PSK31 or "Phase Shift Keying, 31 Baud", also BPSK31 and QPSK31, is a popular computer-sound card-generated radioteletype mode, used primarily by amateur radio operators to conduct real-time keyboard-to-keyboard chat, most often using frequencies in the high frequency amateur radio bands (near-shortwave). PSK31 is distinguished from other digital modes in that it is specifically tuned to have a data rate close to typing speed, and has an extremely narrow bandwidth, allowing many conversations in the same bandwidth as a single voice channel. This narrow bandwidth makes better use of the RF energy in a very narrow space thus allowing relatively low-power equipment (5 watts) to communicate globally using the same skywave propagation used by shortwave radio stations. History PSK31 was developed and named by English amateur radio operator Peter Martinez (call sign G3PLX) and introduced to the wider amateur radio community in December 1998. The 31 baud BPSK modulation system u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wi-Fi
Wi-Fi () is a family of wireless network protocols, based on the IEEE 802.11 family of standards, which are commonly used for local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio waves. These are the most widely used computer networks in the world, used globally in home and small office networks to link desktop and laptop computers, tablet computers, smartphones, smart TVs, printers, and smart speakers together and to a wireless router to connect them to the Internet, and in wireless access points in public places like coffee shops, hotels, libraries and airports to provide visitors with Internet access for their mobile devices. ''Wi-Fi'' is a trademark of the non-profit Wi-Fi Alliance, which restricts the use of the term ''Wi-Fi Certified'' to products that successfully complete interoperability certification testing. the Wi-Fi Alliance consisted of more than 800 companies from around the world. over 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GPS Receiver
A satellite navigation device (satnav device) is a user equipment that uses one or more of several global navigation satellite systems (GNSS) to calculate the device's geographical position and provide navigational advice. Depending on the software used, the satnav device may display the position on a map, as geographic coordinates, or may offer routing directions. As of September 2020, there were four operational GNSS systems, the original United States' Global Positioning System (GPS), the European Union's Galileo, Russia's GLONASS, and China's BeiDou Navigation Satellite System. The Indian Regional Navigation Satellite System (IRNSS) will follow and Japan's Quasi-Zenith Satellite System ( QZSS) scheduled for 2023 will augment the accuracy of a number of GNSS. A satellite navigation device can retrieve location and time information from one or more GNSS systems in all weather conditions, anywhere on or near the Earth's surface. Satnav reception requires an unobstr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Repeater
In telecommunications, a repeater is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction. Some types of repeaters broadcast an identical signal, but alter its method of transmission, for example, on another frequency or baud rate. There are several different types of repeaters; a telephone repeater is an amplifier in a telephone line, an optical repeater is an optoelectronic circuit that amplifies the light beam in an optical fiber cable; and a radio repeater is a radio receiver and transmitter that retransmits a radio signal. A broadcast relay station is a repeater used in broadcast radio and television. Overview When an information-bearing signal passes through a communication channel, it is progressively degraded due to loss of power. For example, when a telephone call passes through a wire telephone line, some of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superheterodyne Transmitter
Superheterodyne transmitter is a radio or TV transmitter which uses an intermediate frequency signal in addition to radio frequency signal. Types of transmitters There are two types of transmitters. In some transmitters, the information signal ( audio (AF), video (VF) etc.) modulates the radio frequency (RF) signal. These direct modulation transmitters are relatively simple transmitters. In more complicated transmitters which are called superheterodyne, the information signal modulates an intermediate frequency (IF) signal. After stages for correction, equalization and sometimes amplification, the IF signal is converted to an RF signal by a stage named frequency mixer or frequency converter. Superheterodyne transmitters are more complex than direct modulation transmitters. Mathematical approach Let : f (t) be the information signal :\omega_ be the angular RF, :\omega_ be the angular IF and :\omega_ be the angular subcarrier frequency. In direct modulation transm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
D-STAR
D-STAR (Digital Smart Technologies for Amateur Radio) is a digital voice and data protocol specification for amateur radio. The system was developed in the late 1990s by the Japan Amateur Radio League and uses minimum-shift keying in its packet-based standard. There are other digital modes that have been adapted for use by amateurs, but D-STAR was the first that was designed specifically for amateur radio. Several advantages of using digital voice modes are that it uses less bandwidth than older analog voice modes such as amplitude modulation and frequency modulation. The quality of the data received is also better than an analog signal at the same signal strength, as long as the signal is above a minimum threshold and as long as there is no multipath propagation. D-STAR compatible radios are available for HF, VHF, UHF, and microwave amateur radio bands. In addition to the over-the-air protocol, D-STAR also provides specifications for network connectivity, enabling D-STAR ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Icom Incorporated
is a Japanese manufacturer of radio transmitting and receiving equipment, founded in 1954 by Tokuzo Inoue with the company's original name being "Inoue". Its products now include equipment for radio amateurs, pilots, maritime applications, land mobile professional applications and radio scanner enthusiasts. Its headquarters are in Osaka, Japan, with branch offices in the United States (in Kirkland, Washington), Canada (in Delta, British Columbia), Australia (Melbourne, Victoria), New Zealand (Auckland), the United Kingdom (Kent, England), France (Toulouse), Germany (Bad Soden), Spain (Barcelona) and the People's Republic of China (Beijing). Protocols IDAS IDAS is Icom's implementation of the NXDN protocol for two-way digital radio products intended for commercial Private Land Mobile Radio (PLMR) and low-end public safety communications systems. NXDN is a Common Air Interface (CAI) technical standard for mobile communications. It was developed jointly by Icom and Kenwood C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Radio Operating Award
An amateur radio operating award is earned by an amateur radio operator for establishing two-way communication (or "working") with other amateur radio stations. Awards are sponsored by national amateur radio societies, radio enthusiast magazines, or amateur radio clubs, and aim to promote activity on the amateur radio bands. Each award has its own set of rules and fees. Some awards require the amateur radio operator to have contacted other stations in a certain number of countries, Maidenhead grid locators, or counties. Because amateur radio operators are forbidden by regulation to accept financial compensation for their on-air activity, award recipients generally only receive a certificate, wooden plaque, or a small trophy as recognition of their award. Most amateur radio operating awards require that the applicant submit proof, such as QSL cards, of the contacts which satisfy the requirements of the award. There are thousands of operating awards available. The most pop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
