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Amateur radio,Q codes ,Morse code ,pronunciation,hs4kff,Radio amateurs
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 16-03-2008, 03:29:11
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| zone 1 |
E22DLH |
| zone 2 |
E27BID |
| zone 3 |
HS3RCT |
| zone 4 |
HS4RKI |
| zone 5 |
HS5YUS |
| zone 6 |
HS6UYH |
| zone 7 |
E29ST |
| zone 8 |
HS8XRZ |
| zone 9 |
HS9SFD |
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 Amateur radio
Amateur radio, often called hamradio, is both a hobby and a service that uses various types of radio communications equipment to communicate with other radio amateurs for public service, recreation and self-training. A participant is called an amateur radio operator, or a ham
Amateur radio operators have personal wireless communications with friends, family members, and even complete strangers, and often support their communities with emergency and disaster communications while increasing their personal knowledge of electronics and radio theory. An estimated six million people throughout the world are regularly involved with amateur radio
The term "amateur" is not a reflection on the skills of the participants, which are often quite advanced; rather, "amateur" indicates that amateur radio communications are not allowed to be made for commercial or money-making purposes.
Though its origins can be traced to at least the late 1800s, amateur radio, as practiced today, began in the 1920s. As with radio in general, the birth of amateur radio was strongly associated with various amateur experimenters and hobbyists. Throughout its history, amateur radio enthusiasts have made significant contributions to science, engineering, industry, and social services. Research by amateur radio operators has founded new industries, built economies, empowered nations, and saved lives in times of emergency.Though its origins can be traced to at least the late 1800s, amateur radio, as practiced today, began in the 1920s. As with radio in general, the birth of amateur radio was strongly associated with various amateur experimenters and hobbyists. Throughout its history, amateur radio enthusiasts have made significant contributions to science, engineering, industry, and social services. Research by amateur radio operators has founded new industries, built economies, empowered nations, and saved lives in times of emergency.
Activities and practices
Radio amateurs use various modes of transmission to communicate. Voice transmissions are most common, with some such as frequency modulation (FM) offering high quality audio, and others such as single sideband (SSB) offering more reliable communications when signals are marginal and bandwidth is restricted Radiotelegraphy using Morse code remains popular, particularly on the shortwave bands and for experimental work such as Moonbounce, with its inherent signal-to-noise ratio advantages. Morse, using internationally agreed code groups, also facilitates communications between amateurs who speak different languages.[3] It is also popular with homebrewers as CW-only transmitters are simpler to construct. For many years, demonstrating a proficiency in Morse code was a requirement to obtain amateur licenses for the high frequency bands, but following changes in international regulations in 2003, many countries have now dropped this requirement (the United States Federal Communications Commission did so in 2007).
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Current EME communications
As the albedo of the moon is very low (around 12%), and the path loss over the 770,000 kilometre return distance is extreme (around 309 db), high power (more than 100 watts) and high-gain antennas (more than 35 db) must be used. In practice, this limits the use of this technique to the spectrum at VHF and above.
Recent advances in digital signal processing have allowed EME contacts, admittedly with low data rate, to take place with powers in the order of 100 Watts and a single Yagi antenna.
moon bounce" technique was developed by the United States Military in the years after World War II, with the first successful reception of echoes off the moon being carried out at Fort Monmouth, New Jersey on January 10, 1946 by John H. DeWitt as part of Project Diana. This was followed by more practical uses, including a teletype link between the naval base at Pearl Harbor, Hawaii and United States Navy headquarters in Washington, DC. In the days before communications satellites, a link free of the vagaries of ionospheric propagation was revolutionary.
Later, the technique was used by non-military commercial users, and the first amateur detection of signals from the moon took place in 1953. |
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Licensing
In all countries, amateur radio operators are required to pass a licensing exam displaying knowledge and understanding of key concepts. In return, hams are granted operating privileges in larger segments of the radio frequency spectrum using a wide variety of communication techniques with higher power levels permitted. This practice is in contrast to other unlicensed personal radio services such as CB radio, Multi-Use Radio Service, or Family Radio Service / PMR446 that require type-approved equipment restricted in frequency range and power.A handheld VHF/UHF transceiver, 2007.In many countries, amateur licensing is a routine civil administrative matter. Amateurs are required to pass an examination to demonstrate technical knowledge, operating competence and awareness of legal and regulatory requirements in order to avoid interference with other amateurs and other radio services. There are often a series of exams available, each progressively more challenging and granting more privileges in terms of frequency availability, power output, permitted experimentation, and in some countries, distinctive callsigns. Some countries such as Great Britain and Australia have begun requiring a practical training course in addition to the written exams in order to obtain a beginner's license. These beginner's licenses are referred to as Foundation Licenses.Amateur radio licensing in the United States serves as an example of the way some countries award different levels of amateur radio licenses based on technical knowledge. Licensees previously needed to demonstrate proficiency in Morse Code to obtain or upgrade a license. These requirements were phased out by the Federal Communications Commission, first from the entry-level Technician license in 1991, and eventually from all license classes on February 23, 2007 This conforms with international law, which no longer mandates Morse code testing, as well as views by the FCC that Morse code should be treated like other communications techniques, and that written testing is sufficient to prove that an applicant is qualified to obtain an amateur radio license Some portions of the ham bands remain reserved for Morse code use only and the mode remains popular.
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EME (communications)
Earth-Moon-Earth, also known as moon bounce, is a radio communications technique which relies on the propagation of radio waves from an earth-based transmitter directed via reflection from the surface of the moon back to an earth-based receiver.
Current EME communications
As the albedo of the moon is very low (around 12%), and the path loss over the 770,000 kilometre return distance is extreme (around 250 dB depending on VHF-UHF band used), high power (more than 100 watts) and high-gain antennas (more than 35 dB) must be used. In practice, this limits the use of this technique to the spectrum at VHF and above. Recent advances in digital signal processing have allowed EME contacts, admittedly with low data rate, to take place with powers in the order of 100 Watts and a single Yagi antenna.
Modulation types and frequencies optimal for EME.
VHF: |
CW , JT65A , JT65B |
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UHF : |
CW , JT65C ,SSB |
Microwav : |
Cw , SSB |
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From : Wikipedia, the free encyclopedia |
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Heb jij "The Right Stuff", wordt astronaut
 De Amerikaanse ruimtevaart organisatie NASA is op zoek naar nieuwe studenten voor de opleiding tot astronaut in 2009. De NASA zoekt een paar mannen en vrouwen die hun droom in vervulling willen zien gaan en deelnemen aan de volgende generatie ontdekkingsreizigers.
More >>>
Unallocated and unavailable call sign prefixes
Unallocated: The following call sign prefixes are available for future allocation by the ITU. (x represents any letter; n represents any digit from 29.)
E6, E8, E9, H5, J9, On, S4, T9*, Un, V9, Xn, YZ*, Z4Z9, 4N*.
(* Indicates a prefix that has recently been returned to the ITU.)
Unavailable: Under present ITU guidelines the following call sign prefixes shall not be allocated[1]. They are sometimes used unofficially - such as amateur radio operators operating in a disputed territory or in a nation state that has no official prefix (e.g. S0 in Western Sahara or 1A at Knights of Malta headquarters in Rome). (x represents any letter; n represents any digit from 29.)
nn, x0, x1, 0x, 1x, Qx.
no prefixes beginning with Q are usedthey may be confused with Q codes.
no prefixes with the digits 1 or 0 are usedthey may be confused with the letters I or O.
two digit prefixes (nn) are not as yet considered by the ITU. |
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Alphabet and pronunciation
The pronunciation of the words in the alphabet as well as numbers may vary according to the language habits of the speakers. In order to eliminate wide variations in pronunciation, posters illustrating the pronunciation desired are available from the ICAO.
| Letter |
Code word |
Pronunciation |
| A |
Alfa
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AL FAH |
| B |
Bravo |
BRAH VOE |
| C |
Charlie |
CHAR LEE |
| D |
Delta |
DELL TAH |
| E |
Echo |
ECK OH |
| F |
Foxtrot |
FOKS TROT |
| G |
Golf |
GOLF |
| H |
Hotel |
HO TELL
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| I |
India |
IN DEE AH |
| J |
Juliet |
JEW LEE ETT |
| K |
Kilo |
KEY LOH |
| L |
Lima |
LEE MAH |
| M |
Mike |
MIKE |
| N |
November |
NO VEM BER |
| O |
Oscar |
OSS CAH |
| P |
Papa |
PAH PAH |
| Q |
Quebec |
KEH BECK |
| R |
Romeo |
ROW ME OH |
| S |
Sierra |
SEE AIR AH |
| T |
Tango |
TANG GO |
| U |
Uniform |
YOU NEE FORM |
| V |
Victor |
VIK TAH |
| W |
Whiskey |
WISS KEY |
| X |
X-ray or
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ECKS RAY |
| Y |
Yankee |
YANG KEY |
| Z |
Zulu |
ZOO LOO |
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Radio frequency
Radio frequency, or RF, is a frequency or rate of oscillation within the range of about 3 Hz and 300 GHz. This range corresponds to frequency of alternating current electrical signals used to produce and detect radio waves. Since most of this range is beyond the vibration rate that most mechanical systems can respond to, RF usually refers to oscillations in electrical circuits.
Special properties of RF electrical signals
Electrical currents that oscillate at RF have special properties not shared by direct current signals. One such property is the ease with which it can ionize air to create a conductive path through air. This property is exploited by 'high frequency' units used in electric arc welding. Another special property is an electromagnetic force that drives the RF current to the surface of conductors, known as the skin effect. Another property is the ability to appear to flow through paths that contain insulating material, like the dielectric insulator of a capacitor. The degree of effect of these properties depend on the frequency of the signals.
Wavelength
In physics, wavelength is the distance between repeating units of a propagating wave of a given frequency. It is commonly designated by the Greek letter lambda (?). Examples of wave-like phenonomena are light, water waves, and sound waves.Wavelength of a sine wave.In a wave, a property varies with the position. For example, this property can be the air pressure for a sound wave, or the magnitude of the electric or the magnetic field for light. The wavelengths of frequencies audible to the human ear (20 Hz20 kHz) are between approximately 17 m and 17 mm, respectively. Visible light ranges from deep red, roughly 700 nm to violet, roughly 400 nm (430750 THz). For other examples, see electromagnetic spectrum....
Relationship with frequency
Wavelength ? is inverse proportional with the frequency ? (Greek "nu"), the number of wave periods per time unit passing a given point, as in where vw is the propagation velocity of the wave. In the case of electromagnetic radiation, such as light, in a vacuum, this speed is the speed of light, 299,792,458 m/s or about 109 km/h. For sound waves in air, this is the speed of sound, 344 m/s (1238 km/h) in air at room temperature. Usually, SI units are used, where the wavelength is expressed in meters, the frequency in Hz, and the propagation velocity in meters per second
In non-vacuum media
The speed of light in most media is lower than in vacuum, which means that the same frequency will correspond to a shorter wavelength in the medium than in vacuum. The wavelength in the medium iswhere n is the refractive index of the medium. Wavelengths of electromagnetic radiation are usually quoted in terms of the vacuum wavelength, unless specifically indicated as the "wavelength in the medium". In acoustics, unless otherwise specified, the term wavelength is used to mean the wavelength in the medium. |
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ARISS to Conduct Simulation QSO between Astronauts and Students (Feb 5, 2008)
-- Before each trip to the International Space Station (ISS), astronauts who hold Amateur Radio licenses are trained by a team of Amateur Radio on the International Space Station (ARISS) members on ARISS procedures and how to use the onboard radios. To make this training more realistic for the astronauts, ARISS has arranged for crewmembers in training at Johnson Space Center to participate in two simulated ARISS contacts with a local Houston school.
Students at Bay Area Charter Elementary in El Lago, Texas will conduct two sessions on Friday, February 8 between 1545 UTC and 1610 UTC. According to ARRL ARISS Program Manager Rosalie White, K1STO, these times may fluctuate somewhat depending on how well training is going and crewmember availability. Astronaut Mike Fincke, KE5AIT, is scheduled to participate in the first event; Koichi Wakata, KC5ZTA, will participate in the second event. White said this is the first (and second) time a school contact simulation training session has been conducted live where students are at the other end of the session. If this proves successful, she said it might be possible to conduct a handful of these sessions each year: "If things go well, this can increase somewhat our opportunities for schools. In the past, we found that kids were equally excited when their school's QSO was done with an astronaut sitting at Johnson Space Center's Amateur Radio station W5RRR [as opposed to a contact from space]." Simulations are not as predictable as on-orbit operations, so there is a slight chance the event might be postponed.....
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Morse code
Morse code is a method for transmitting telegraphic information, using standardized sequences of short and long elements to represent the letters, numerals, punctuation and special characters of a message. The short and long elements can be formed by sounds, marks or pulses, in on off keying and are commonly known as "dots" and "dashes" or "dits" and "dahs".
International Morse code is composed of six elements:
1.
short mark, dot or 'dit' (?)
2. longer mark, dash or 'dah' (-)
3. intra-character gap (between the dots and dashes within a character)
4. short gap (between letters)
5.
medium gap (between words)
6.
long gap (between sentences about seven units of time)
These six elements serve as the basis for International Morse code and therefore can be applied to the use of Morse code world-wide.
Morse code can be transmitted in a number of ways: originally as electrical pulses along a telegraph wire, but also as an audio tone, a radio signal with short and long tones, or as a mechanical or visual signal (e.g. a flashing light) using devices like an Aldis lamp or a heliograph. Morse code is transmitted using just two states (on and off) so it was an early form of a digital code. However, it is technically not binary, as the pause lengths are required to decode the information.
Originally created for Samuel F. B. Morse's electric telegraph in the early 1840s, Morse code was also extensively used for early radio communication beginning in the 1890s. For the first half of the twentieth century, the majority of high-speed international communication was conducted in Morse code, using telegraph lines, undersea cables, and radio circuits. However, the variable length of the Morse characters made it hard to adapt to automated circuits, so for most electronic communication it has been replaced by more machinable formats, such as Baudot code and ASCII.
The most popular current use of Morse code is by amateur radio operators. Although no longer a requirement for Amateur licensing in most countries, it also continues to be used for specialized purposes, including identification of navigational radio beacon and land mobile transmitters, plus some military communication, including flashing-light semaphore communications between ships in some naval services. Morse code is the only digital modulation mode designed to be easily read by humans without a computer, making it appropriate for sending automated digital data in voice channels, as well as making it ideal for emergency signaling, such as by way of improvised energy sources that can be easily "keyed" such as by supplying and removing electric power (e.g. by switching a breaker on and off)
Modern International Morse Code
Morse code has been in use for more than 160 years longer than any other electronic encoding system. What is called Morse code today is actually somewhat different from what was originally developed by Vail and Morse. The Modern International Morse code, or continental code, was created by Friedrich Clemens Gerke in 1848 and initially used for telegraphy between Hamburg and Cuxhaven in Germany. After some minor changes, in 1865 it was standardised at the International Telegraphy congress in Paris (1865), and later made the norm by the International Telecommunication Union (ITU) as International Morse code. Morse's original code specification, largely limited to use in the United States, became known as American Morse code or "railroad code." American Morse is now very rarely used except in historical re-enactments.
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ITU prefix
The International Telecommunication Union (ITU) allocates call sign prefixes for radio and television stations of all types. They also form the basis for aircraft registration identifiers. These prefixes are agreed upon internationally, and are a form of country code. A call sign can be any number of letters and numerals but each country must only use call signs that begin with the characters allocated for use in that country.
A few countries do not fully comply with these rules. Australian broadcast stations officially havebut do not usethe VL prefix, and Canada uses Chile's CB for its own Canadian Broadcasting Corporation stations.
With regard to the second and/or third letters in the prefixes in the list below, if the country in question is allocated all callsigns with A to Z in that position, then that country can also use call signs with the digits 2 to 9 in that position. For example, the Thailand States is assigned HSE2, and therefore can also use prefixes like HS0A-Z, or E20A-Z.
Many large countries in turn have internal rules on how and where specific subsets of their callsigns can be used (such as Mexico's XE for AM and XH for FM radio and Television broadcasting), which are not covered here.
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