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USA AMATEUR RADIO HISTORY AND LICENSING
For Broadcast Radio/TV History -- click here
For History of Communications-Electronics in The United States Navy -- Click Here
New Book! The History of Wireless: How Creative Minds Produced Technology For The Masses
by Ira Brodsky
Day One Mother Nature sends static crashes and lightning crashes around the world - but no one is around to hear them!!! Either audibly or by radio - DX will be!!
DX is an early telephone term for distant exchange. It is also defined in Funk & Wagnall's as Distance. The term DX appears in many math formulas as distance of x. See Origin of DX. At any rate, for Amateur Radio, it is the sending of messages over long distances.
EARLY COMMUNICATIONS
The Greeks were the first to discover electricity about 2500 years ago. They noticed that when an amber was rubbed with other materials it became charged with an unknown force that had the power to attract objects such as dried leaves, feathers, bits of cloth, or other lightweight materials. The Greeks called amber electron. The word electric was derived from it and meant "to be like amber," or to have the ability to attract other objects.
1200 BC In the Iliad, Homer tells of a chain of beacon fires prearranged to signal the return of Agamemnon's fleet to Mycenae and, thus, gave Clytemnestra and Aegisthus time to arrange the assassination of Agamemnon.23
522 BC Persian Army employs a relay system where soldiers positioned on hilltops shout and relay military messages 30 times faster than by runner. Accounts of flags, mirrors and smoke signals appear in early history.
490 B.C Greek runner Pheidippides, Athenian courier is sent to Sparta to request help when the Persians landed at Marathon - runs 150 miles in two days. At the conclusion of the battle, he returns to Athens, where he reportedly shouted “Rejoice! We conquer!ö and then died of exhaustion.
Early On - Mirrors are used to signal across visible distances - the heliograph
1206 Genghis Khan is denied importing of radio gear, so develops a "pony express" to keep tabs on his empire -- pony stations at about 25 miles apart.
1500 -1800's Early discoveries of Electricty and Magnetism can be found in the annals of history, names such as Gilbert, Von Guericke, Volta, Oersted, Wheatstone, Cooke, Faraday, Ampere, Ohm, Davy, all contribute to the ultimate development of wireless.
1610 - Galileo observes sunspots through his telescope. He also experiments extensively in the fields of mechanics, astronomy, the microscope, thermometry, and magnetism.
1749-1755 “Firstö solar cycle observed in Zurich, Switzerland. Solar Cycle 1700-2000
1823 In England, Sir Francis Ronalds builds a 'telegraph' in his garden; no one is interested. 23
1831 - 1903. Early Pioneers and Inventors include, Maxwell, Marconi, Loomis, Edison, Henry, Hertz, Feddersen, Von Bezold, Hughes, Stokes, Tesla, Henry, Bell, Preece, Hertz, Branly, Dodge, Braun, Lodge, and Popoff all lay the foundation of wireless 14
1835 Samuel F. B. Morse formulates the elements of a relay system. By 1837 the system is improved and was demonstrated using 'lightning wires' and 'Morse code,' an electronic alphabet that could carry messages. The patent was applied for in 1840. A line was constructed between Baltimore and Washington and the first message, sent on May 24,1844, was 'What hath God wrought!'
1861 the two coasts of the United States were linked by telegraph. The operating procedures, codes and protocols of the telegraph were carried over to the new age of "wireless". Indeed many wireless operators came from the telegraph ranks.
1861 - 1865 During the US Civil War, Telegraph is used extensively using existing commercial systems, and building and operating more than fifteen thousand miles of lines for military purposes only.
THE BIRTH OF WIRELESS
The term wireless was a natural extension of less wired or the telegraph. Not until 1906 did the term Radio begin to appear.
1850 - By 1850 most of the basic electrical phenomena had been investigated. However, James Clerk Maxwell (1831-1879), Professor of Experimental Physics at Cambridge then came up with something entirely new. By some elegant mathematics he had shown the probable existence of electromagnetic waves of radiation. But it was twenty four years later (eight years after Maxwell's death) that Heinrich Hertz (1857-1894) in Germany gave a practical demonstration of the accuracy of this theory. He generated and detected electromagnetic waves across the length of his laboratory on a wavelength of approximately one metre.16
1864 Mahlon Loomis 1 proposes a vertical top-capacity loaded aerial with a keying device and an indicator, all in series to ground. DX Might Be!
1865 Using 2 kites, Mahlon Loomis 2 transmits wireless messages between two mountains 18 miles apart in Virginia. Son Of A Gun - DX IS. The first Dxpedition???
1865 - On 17 May 1865 the first International Telegraph Convention was signed by the 20 participating countries and the International Telegraph Union (later ITU) was set up to enable subsequent amendments to this initial agreement to be agreed upon13
1870 Mahlon Loomis successfully transmitted wireless telegraphic signals between two ships which were two miles apart on the Chesapeake Bay. The U. S. Navy sponsored those experiments.
1876 They were thinking about Television. Get the History of TV -- From The FCC
1883 Edison demonstrated that an electric current could pass between a heated filament and a cold plate in a vacuum.
1886 Heinrich Hertz proved that electromagnetic waves could be sent through space.
1887 Heinrich Hertz experments with parbolic dishes - produces waves at about 30cm - 1 GHz!!!
1896 - First practical wireless by Marconi, 'Hertzian Waves' over two miles! DX Will Be! When he read about the experiments of Heinrich Hertz and about Popov's suggestion, he saw the possibility of using these waves as a means of signaling. Marconi realized that his signaling system would be most useful to shipping.
1898 -- In January, British Leslie Miller 3 publishes an article in the British hobby magazine "The Model Engineer and Amateur Electrician". Here he contributed a superbly written article titled "The New Wireless Telegraphy" encouraging experimenters in the new field of "Wireless".
1898 - US Navy establishes coastal stations and begins to outfit the fleet with wireless communications.
1898 - 1912, experimenters begin transmitting and DX is anything over 10 miles. Early Amateur Radio in the UK can be seen at Dawn Of Radio in the UK and Europe16
1899 Marconi sends a signal over the English Channel - 32 miles. QSL's are in order.
1901 Marconi bridges the Atlantic, a feat which caught the world's attention and fueled the imagination of thousands of potential amateurs, who took their first steps into wireless. His transatlantic triumph came on the 12th December 1901 when the morse letter 'S' was transmitted from Poldhu, in Cornwall and received by Marconi himself at St. John's, Newfoundland, who recorded the historic event in his pocket book simply "Sigs at 12.20, 1.10 & 2.20".
Marconi's original transmitters used high voltage spark gaps to generate 'Hertzian Waves'. The first experimental sets used induction coils with vibrating contact current interrupters to generate the high voltages.
In the way of development after Marconi's high voltage spark gap came the use of high voltage transformers to generate the spark gap voltage. The ultimate came in the powerful transmitters such as those at the U.S. Navy's station at Arlington, Virginia. Here a 500 Hz generator, a step up transformer, and a rotary spark gap was used used to create the high voltage. Some of these produced a deafening noise created by the spark. Spark transmitters were often placed in acoustically insulated rooms to deaden the sound.
Around 1900 William Duddell discovered the principle of negative resistance in connection with a carbon arc. By adding a resonant circuit to the arc it would oscillate at a frequency determined by the LC constants. Duddell's arc would only oscillate at audio frequencies, audible to human hearing, and it was dubbed the "singing arc."
In 1902 Valdemar Poulsen, succeeded in making the arc oscillate at the higher frequencies by using electrodes operating in a sealed chamber, with hydrocarbon vapor, and a strong magnetic field. The arc became the first transmitter capable of generating pure, undamped waves. Arc transmitters were widely used at both shore stations and on ships. They were complicated to operate and were infamous for exploding when an operator introduced too much alcohol into the chamber. Arc transmitters were brought to the United States in 1909.
One of the more powerful arc transmitters constructed were the 1,000 watt units built for the U.S. Navy at Bordeaux, France, during World War I. In Java, a unit was rated at 3,000 W, the antenna was suspended over a mountain gorge. By gradually scaling up the equipment Federal Telegraph finally produced a 30 kW unit that outperformed a powerful rotary spark transmitter at the Navy's Arlington station. The navy wanted still more power and Elwell thought he could build a 60 kW unit by merely scaling up the parts again. But it didn't work. Arc transmitters were gradually eliminated when the new vacuum tube transmitters came into use. However, many were used up to World War II. Perhaps the last to be in operation on land were the stations operated by the Mackay Radio and Telegraph Company between cities on the Pacific coast.
A synchronous rotary had the spark electrodes mounted on the shaft of the motor generator which feeds a HV step up transformer. In this way, the spark would discharge the capacitor synchronously with the peak in the AC waveform. In a non-synchronous gap, the discharge could occur anywhere within the cycle. Buzzer were sometimes used to supply the voltage to an induction coil in early spark coil sets, since they had a higher "tone" than what some other interrupters could produce. Buzzers were used early on as a way to get ICW ( interrupted CW ) signals in early vacuum tube transmitters. The buzzer would interrupt the CW at an audio rate, thus modulating the CW carrier. You could detect the signal with a non-oscillating detector.10 Also see Fessenden and the Early History of Radio Science where the concept of an HF Alternator is discussed.20
1902 - Nathan Stubblefield Kentucky farmer invents wireless telephone! But was it radio? Facts and folklore about Nathan Stubblefield by Bob Lochte24.
1902 Oliver Heaviside predicted that there was an conducting layer in the atmosphere which allowed radio waves to follow the Earth's curvature. This layer in the atmosphere, the Heaviside layer, is named after him. Its existence was proved in 1923 when radio pulses were transmitted vertically upward and the returning pulses from the reflecting layer were received. Propagation has always been the life blood of long distant radio communications and from the early days, Amateurs carefully watched propagation conditions as they do today.
Early wireless codes was The American Morse code, International code and U. S. Navy code11
1904 Sir John Ambrose Fleming worked to develop the first rectifier and in 1904, while working for the Marconi Company, he was faced with the problem of detecting weak wireless signals. He was inspired by his work with Edison’s lamps back in 1889 and decided to try inserting one of the lamps in an oscillatory circuit containing a galvanometer. He had found the solution to the problem of rectifying high frequency wireless circuits.
HISTORY OF VACUUM TUBES - A MUST SEE
1904 One of the first companies to sell radio equipment to experimenters and amateurs was the Electro Importing Company of New York City, set up in 1904 by Hugo Gernsback.
1905 Guglielmo Marconi patented his directive horizontal antenna.23 (A Beam Antenna!!)
1905 Horace G. Martin introduces the The Vibroplex semi-automatic telegraph key, commonly called a "bug". The Use of 500 kHz as the International Distress Frequency is common.
1906 First wireless communication of human speech (and music) on December 24, 1906. Fessenden spoke and broadcasted music by radio from Brant Rock, Massachusetts, to ships in the Atlantic Ocean using a two kilowatt (100 kHz) alternator developed by Alexanderson. Fessenden modulates continuous wave. 23
1906 November 3. The "Berlin International Wireless Telegraph Convention" 4 defined call letters, operating procedures and signals for Coastal Stations and ships at sea. The committee decided that henceforth the term "Radio" would better describe wireless. Radio is derived from the Latin radius (ray or beam of light). The term wireless lingered for many years, but by 1912 the term Radio was used in legislation. Some countries even today are fond of the word wireless. Radio Shack probably gets its name from maritime lore dating back to the invention of the radio at the turn of the century. At the time, wireless equipment aboard ships was generally housed above the bridge in a wooden structure that was called the "radio shack".
1906, Lee De Forest added a third electrode to the diode, the "triode" or "audion" tube could both rectify and amplify; and its greater control it meant that various electronic circuits would finally be commercially feasible.
1908 Hugo Gernsback published his first magazine, Modern Electrics (later to become Electrical Experimenter) which does much to foster and popularize Amateur Radio.
1909, On January 2, the first amateur radio club; The Junior Wireless Club, Limited, of New York City, was organized. Later the club name changed to Radio Club Of America, and their history is a must read, don't miss it.
1909 Young radio amateurs are building receivers with whatever parts are available. Although headphones can be purchased...many public telephone booths become inoperative.23 N6AW reports there are many examples of home brew receivers at the Antique Wireless Association museum in Bloomfield, NY dating to prior to 1909. It seems that very early on the young experimenters figured out that given a little wire for a coil & antenna, a home-made detector described in Modern Electrics or Hugo Gernsback's catelogue and a pair of headphones (some were homemade) they were all set. Don Wallace was first on the air in 1909 with a self-assigned call and working his buddy a block away with a spark coil from a Ford.
1909 First Callbook issued - 1909 The Wireless Blue Book (pdf courtesy University of Pennsylvania Amateur Radio Club (link goes to club history) -- thx go to Russ WA3FRP!). Today many Amateur Radio Callbooks are on the web.
1910 Oct 5. The first Cat's Whisker Detector invented by B. F. Miessner who received "The De Forest Audion Award in 1963." This patent was sold to John Firth for "a magnificent sum
of $200". From the "On the Early History of Radio Guidance". Library of Congress Card # is 64-2115.
1910 Senator Depew introduces a bill virtually prohibiting amateur experimenting. The Junior Wireless Club organizes a committee to plead the cause of the amateur before Congress. The bill is squashed and again DX IS!17
1910 THE POULSEN SYSTEM OF WIRELESS TELEPHONY AND
Pre 1912 - Before the advent of Vacuum Tubes14 - various forms of detectors were used including: The Coherer, Lodge Muirhead Coherer, Electrolytic Detector, Carborundum Detector, Fleming Valve, Thermo Electric Detector, and Magnetic Detectors. See World Of Wireless 14 Also see Crystal Sets14
1912 - Edwin H. Armstrong6 uses feedback in an Audion - amplifiers and oscillators now practical.
1912 - April 12, RMS Titanic sinks after encountering an iceberg, the tragic loss of life prompts new international radio laws which also affect Amateur Radio, including frequency restrictions and operating procedures. See the Bill Continelli's History of Amateur Radio.5 Also see excellent article on Radio Aspects of the Titanic Disaster and the Transcript Of The Actual Radio Distress Traffic of the Titanic.
Before 1912, call signs were just made up by the aspiring Amateur and it wasn't until the Radio Act of 1912 that the first licenses were issued. An HTML version of Early Radio Laws 4 is on-line. Very interesting reading as it defines DE, CQ, Operating Procedures, Morse Code of the day, and many Q Signals we still use. In 1911, Hiram Percy Maxim's assumed call was SNY. In 1912, Irving Vermilya, 1ZE, 6 received Skill Certificate No. 1, thus considered as the first licensed Amateur Radio Operator. Some sources indicate the code requirement was 5 wpm (how things go around and come around - 5 wpm now in the year 2000!!!). Written exams included essay type questions -- making a diagram of transmitting and receiving apparatus and how they worked! Also of course International and US Law questions.
For opinions on the origins of Q-signals, Z-codes, X-codes, R-codes, and S-codes, DE, CQ, 33, 73, ham, lid, SOS, mayday, pan-pan, RST system, S-meter, prosigns, roger, wilco, boatanchor -- See Origins. Also each human endeavor seems to develop its own jargon, ham jargon is almost incomprehensible to others and has a rich history -- see Jargon and abbreviations.
1913 Amateurs using Audions in their receivers discovered that distances of up to 350 miles were now possible on 200 meters.
1913 - Radio Call Letter Policies 4 issued by the Department Of Commerce listed the USA with call letters of KDA to KZZ - United States, N - All to the United States, W - All to the United States. This document shows other countries as well. However, for Amateurs, "The call letters for amateur stations in the United States will be awarded by radio inspectors, each for his own district, respectively according to the following system: (a) The call will consist of three items; number of radio district; followed by two letters of the alphabet. Thus, the call of all amateur stations in New England (which comprises the first district) will be the figure "one" in Continental Morse, followed by two letters; in California (in the sixth district) the figure "six" followed by two letters; in South Carolina the figure "four" followed by two letters; in Missouri the figure "nine" followed by two letters, etc. The letters X, Y, Z, must not be used as the first of the two letters". Examples, 1AW, 6OI, 2MN.
Here is a possible explanation as to how the USA got W and K, no documentation on this but sounds plausible. The USA had unofficially used N for North America (e.g., NBZ, Boston), also A for America. The letter "N" in morse is dah dit, adding a dah to N gives dah dit dah which is "K'. Letter "A" in morse is dit dah, adding a dah to A gives dit dah dah which is "W".
Somewhere in this era, an informal system of prefixes evolved and Amateurs used A for Australia, B for Belgium, C for Canada, etc. This single-letter system worked until Amateur Radio spread around the world and there were too many countries for the system to accommodate. Thus, in 1927, a new system took effect using two-letters with the first letter indicating the continent (E for Europe, A for Asia, N for North America, F for Africa, etc.) and the second letter indicating the country. Stations in the 48 United States used an NU call. These were called "Intermediate Prefixes".
With the advent of the Radio Act of 1912, the first Amateur Radio License is issued. The call letters assigned to the United States were NAA -NZZ, WAA - WZZ, and KDA to KZZ (KAA-KCZ was assigned to Germany and was not given to the United States until 1929). The somewhat puzzling Amateur calls like 1AW, 6OI, 2MN, etc. is explained by the fact that Amateur stations did not qualify for international call signs. At that time, the USA was divided into nine Radio Districts so Amateurs were granted calls consisting of their district number followed by letters, the first letter was from A through W, for example, 1AW, 1TS. Recognition was given to certain land stations, X as the first letter for Experimental licenses (e.g. 1XE), Y for School licenses (e.g. 9YY), and Z for Special Amateur licenses (e.g. 8ZZ). 1x3 calls (like 1AAA) was issued to Amateurs beginning in 1914. For a list of early X, Y, Z callsign issues -- see U.S. Special Land Stations: 1913-1921.4 It was not until October 1, 1928, that the W and K prefixes were assigned to Amateurs.
Amateurs were relegated to 200 meters and down and shocked the world with making excellent use of these higher frequencies -- see "200 Meters and Down" by Clinton B. DeSoto.
1913 to 1980’s Don Wallace12 W6AM. DX Hall of Fame and early pioneer of Amateur radio. Don has probably done more to promote DX operation and encourage new operators than any other individual. Famous for his antenna farms in Rolling Hills on the Palos Verdes peninsula. N6AW reports Don was first licensed in 1913 as 6OC, and he first appears in Radio Stations of the US, supplement 3 to the first edition, spring 1914. (1st ed. published in 1913). He received 6AM in 1926, W6AM in 1928.
1914 - The ARRL is organized by Hiram Percy Maxim to help relay messages, typical ranges were 25 miles. QST magazine appears in 1915. Hiram Percy Maxim was the son of Sir Hiram Stevens Maxim who invented the machine gun (the Devil's Paint Brush), father and son are often confused, although Hiram Percy Maxim did invent a weapons silencer.
1914 Frederick E. Terman 6AE is operating out of Palo Alto, CA. Later he publishes "Radio Engineering" in 1932 and the Radio Engineers's Handbook in 1943, 1955, which becomes the bible for engineers and technicians alike during the vacuum tube era. . He is also famous for persuading young Bill Hewlett and David Packard to stay in California instead of going East to start their electronics business.
1915 Ray Kellog invents the The electric ( moving coil ) loudspeaker. 23
1915 John R. Carson applied for a patent on his idea to suppress the carrier and one sideband. 25 Also See Ham Speak and Origins
1916 Amateur Station 2IB works 8AEZ Lima Ohio - 750 miles across the USA
1916 Amateur station 2PM succeeded in breaking all records by sending the first transcontinental relay message from New York to California. Several weeks later the same station and the same operators succeeded in getting signals to California, a distance of some 2,500 miles over-land17
Note that the NAA -NZZ, WAA - WZZ, and KAA to KZZ allotments are used for all broadcasting stations, aircraft, marine, police, fire, MARS and just about anything else that uses a radio. Although the N numbers on aircraft are registration numbers with the FAA, private planes use them legitimately for their "Radio Call". CB at one time had calls like KEV9506 (mine) until this was done away with. Now CB, FRS, and special low power services do not require a license. GMRS does require a license -- see CB and Family Radio Service.
Amateur N call usage has been very limited until the 1970's, but some notable exceptions at N - CALLS
1917 - There were about 6,000 Amateurs. By 1917, code speed requirements were increased to 10 wpm. Amateur radio was shut down during WWI and the Navy even issued orders against receiving as well. Amateurs get back on the air in October - November, 1919.
1918 - The superheterodyne-principle is discovered by Armstrong. Equipment homebrew and manufacturers switch from direct conversion to superheterodynes around 193414
1918 - The first crystal (Rochelle salt) controlled oscillator is invented by A.M. Nicolson.
1919 Marconi and Fleming both assume strong positions on fostering "Amateur Radio". Perhaps without them the Amateur Radio Service might not exist today.16
1919 E. Kaleveld PA0XE claims that the first QSL was issued 1919 by C. D. Hoffmann, 8UX, but there is no example in existence. Nor is there a record in "Wireless World" or in any other known contemporary publication supporting the claim of 2UV to have issued the first authentic QSL card in Europe or the date it was used. "Wireless World" reproduced a post card bearing the call 8ML in the issue dated May 5, 1923, and this, according to the caption, was "one of the specially printed cards circulated in America by members of the ARRL for reporting the reception of experimental mtransmissions", and advocated the adoption in the United Kingdom of a similar type of card for acknowledging reports.
1919--President Woodrow Wilson broadcasts to American Troops in Europe, the first Presidential radio broadcast.
1919 The Alexander Bill proposed to give the government - specifically the Navy Dept - control of all transmitting, and leave amateurs out in the cold. There are articles about this in about this in the Jan, Feb, and Mar, 1919, "Electrical Experimentor". Gernsback claims to have killed the Bill and so does the ARRL, per the 1936 "Radio Amateur's Handbook", claims that Hiram Percy Maxim killed it with a single handed job of personal lobbying in Washington. Perhaps both did.
1920 The Radio Amateurs Callbook (RAC, Flying Horse) is published. International QSL bureaus are establihed.
1920 October 27th -- first licensed Broadcast Station KDKA, Pittsburg, PA. For the History of Broadcast Radio -- also has a list of the first 100 BC Stations. Another is Broadcasting History Links.
1920 The Ladies Of Early Radio6 Perhaps the first woman to be both an announcer and an engineer was Eunice Randall. At the age of 19, she was broadcasting on 1XE, a Boston-area radio station owned by AMRAD. Soon after, she was deeply involved with both professional and amateur radio, building her own ham station, and ultimately became one of the first women in New England to hold the first class license (her ham calls were 1CDP, and later W1MPP).
1921 - ARRL membership numbers 6,000 transmitting members.
1921 - Practical horn loudspeakers were developed.
1921 - The Transatlantic Tests Paul Godley 2ZE (a prominent U.S. amateur) traveled to England with US equipment and operating from Ardrossan, a coast town near Glasgow, Scotland. At 00.50 GMT on December 9th 1921, he identified signals from 1BCG located at Greenwich, Connecticut. Two days later the historic first complete message transmitted by U.S. amateurs and received in Europe on the "short waves" (actually 230 metres) heralded a new era. The message read: No.1 de 1BCG. Words 12. New York December 11 1921. To Paul Godley Ardrossan Scotland. Hearty Congratulations. Signed Burghard Inman Grinan Armstrong Amy Cronkhite. In the summer of 1922 amateurs in France began to get licences and Leon Deloy 8AB President of the Radio Club of Nice in southern France started hearing British stations. After a visit to the U.S.A. Deloy was able to improve his equipment and on November 27th 1923 he contacted Fred Schnell 1MO of West Hartford, Connecticut for the first ever 2-way QSO across the Atlantic. They used the "useless" wavelengths around 100 metres16
1922 Amateur Radio License Requirements for the two grades of licenses, Amateur first grade and Amateur second grade, were the same except the second grade license was issued only where an applicant could not be personally examined by a US Radio Inspector for the district. Applicants were required to demonstrate technical expertise in adjusting and operating equipment, and a knowledge of International Conventions and US laws . The code requirement was ability to transmit and receive in the Continental Morse at least 10 words per minute and recognize important signal usage of the day (distress and "keep out" signals). General amateur stations were restricted to 200 meters and down with input power not to exceed 1 kW. Amateurs within five nautical miles of a military station were restricted to 500 Watts.11
1922 Carson describes FM and concludes it is inferior to AM, a decade later Armstrong places a new perspective on the matter.
1923 - Patent granted for SSB. Also See Ham Speak and Origins
1923 Us Bureau Of Standards suggests the use of frequency instead of wavelength.
1923 - WWV began broadcasting time and frequency information from its radio station.
1923, November 27, the impossible happened. Leon Deloy (8AB), of Nice, France worked (on 110 m CW) USA stations: Fred H. Schnell (1MO, Connecticut) and John L. Reinartz (1QP/1XAL, after - W3RB).Four thousand miles - DX For Sure.
1923, from "200 Meters and Down," by Clinton DeSoto, page 85. "It was expected, then, that every effort would be bent toward putting over the fourth transatlantic tests, to be held from December 21st (1923) to January 10th (1924). The widest possible publicity was accorded these tests on both sides of the Atlantic. To facilitate the international identification, an initial letter was assigned to each country to be used by the amateurs of that country ahead of their calls. The United States was given "U"; an American station would sign itself u1AA, for example. For each of the countries participating in the transatlantics: Australia, Canada, France, Great Britain, Italy, Mexico, Netherlands, Portugal, Spain, United States and New Zealand (z). Cuba was assigned the phonetic Q, Argentina the phonetic R. South Africa was arbitrarily given O." These were not official prefixes assigned by any authority, but an informal convention adopted to avoid confusion when transoceanic communications were first becoming "routinely" possible. Later an additional prefix letter was adopted indicating the continent, "N" being North America, so "1AW" would be "Nu1AW".
To be continue...
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