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The History of Amateur Radio

Florence Owens Thompson, mother of 7 young kids, lost her job in 1931 and tried her luck with her family in California. It was pictured by Dorothea Lange in 1936 and became the symbol of Courage of all a nation. She died in 1983. On her tomb is engraved this epitaph: "Migrant Mother–A Legend of the Strength of American Motherhood". Doc Library of Congress.

The 1930s : The Great Depression (VII)

Just after the crash of 1929 in the U.S.A. and Canada, income of almost every family was cut by more than half, and millions people lost their job.

By 1932 the number of unemployed people was huge and increased still : a quarter of the US workforce was without jobs and many people became homeless. President Herbert Hoover attempted to handle the crisis but he was unable to improve the situation.

In 1932, Franklin Delano Roosevelt was elected President of the U.S.A. and promised a "New Deal" for the American people. Congress created The Works Progress Administration (WPA) which offered work relief for thousands of people. But the end of the Great Depression came about only in 1941 with America's entry into World War II after the airraid on Pearl Harbor.

In the meantime, the Great Depression crossed the Atlantic and hit Europe in 1932, generating millions of unemployed people as well.

Non-stop progress

In spite of the Great Depression, the world continued to imagine ideas and create new objects. During the years '30s the progress in science and technology was non-stop. There was the Chicago's second world's fair in 1933-34 and the Exposition Internationale de Paris in 1937.

Now that all receivers and transmitters were equipped with vacuum tubes and that many of them took advantage of a superheterodyne circuit, the spark gap became an old souvenir, just good to be displayed on a shelf or in a museum, reminiscence of a glorious past.

Thanks to Eugene Wigner and his team at Princeton University, the quantum theory met semiconductors, preparing the ground for Bell Labs development of the first transitors twenty years later but, silent, it is still an industrial secret.

The public was also the witness of the discovery of Nylon and the electron microscope. Always ahead on the other nations, the U.S.A. opened the Empire State Building in 1931. The first drive-in movie theater opened in 1933, and during the entr'act the viewers could appreciate the new newspaper Newsweek.

First TV commercial

On July 2, 1928 a new medium appeared. The Federal Radio Commission issues the first television license, W3XK, to Charles Francis Jenkins. Jenkins was a prolific inventor who achieved over 400 patents, including 75 related to television, and many others like the automobile self-starter, radio navigation, paper milk carton technology, reversible propellers, time-lapse photography, and the front-mounted automobile engine...

Jenkins' QSL and two views of the America's first TV station W3XK: a power of 5 kW on 4.95 Mc !

The television invention went back to 1876 when the American George Carey was thinking about complete television systems. In 1877, he put forward drawings for what he called a "selenium camera" that would allow people to "see by electricity".

Many inventors experimented this technology until Jenkins demonstrated in 1925 what he called the "radio vision" to authorities and press. His invention that was looking as a "fantastic dream of science became an accomplished fact". 

On January 15, 1929 amateurs had already the opportunity to see this new medium. For example, the Englishman E.V.R.Martin, 2TL, gave a demonstration of television with his home-constructed transmitter and receiver in the Mechanics' Institute of Derby.

Now, in 1930, Jenkins broadcasted the first TV commercial and in the run the BBC began regular TV transmissions. 

At first, the american television station was limited to primitive silhouette images because of its 10 Kc bandwidth, but soon it was allowed to move its carrier frequency to 4.95 Mc with a bandwidth of 100 Kc and a power of 5 kW. 

The future looked really fantastic: not only we had the sound of radio at home but also the image like at the movies!

First WAC award

In the April 1926 issue of QST, amateurs leant the existence of the "WAC Club", WAC standing for "Worked All Continents". 

Face to interest of amateurs for contests and awards, in 1930 ARRL issued WAC award. It is easy to get. It is delivered to all amateurs affiliated to a national amateur radio society having proved contacts with other amateur stations in each of the six continental areas of the world. For some time it was issued by IARU. Today, as in the U.S.A., IARU Headquarters are the same as ARRL Headquarters, the certificate can be asked to ARRL or one of his official foreign checkpoints.

TVI and first UK licenses

The straight TV receiver was in popular vogue in Europe also, and as a matter of support its interest, the English BBC reported that they had received some 7,023 complaints of interference caused by oscillating detectors ! An interest in direction finding had started among local enthusiasts, possibly due to the dearth of radiating oscillators.

This is in 1934 that amateur radio licenses were issued for the first time in the United Kingdom. The RSGB that was incorporated in 1926 has looked after the interests of the 55,000 English licensed radio amateurs and since that time, its internal rule states that the essential missions of RSGB are to promote the general advancement of the science and practice of radio Communication or other relevant subjects, facilitate the exchange of information and ideas on these subjects among its members, and aim to obtain the maximum liberty of action consistent with safeguarding the interests of all concerned.

Wallace's Panadaptor, the first spectrum analyzer

Panoramic reception was created in 1932 by the French engineer and ham Marcel Wallace, F3HM. The Panadaptor is the first spectrum analyzer portraying visually the signals in a selected part of the radio spectrum, making RF signals visible, identifiable my mode. It worked like does a modern spectrum analyzer or software like DigiPan used for PSK31 activities. This peripheral helped radio operators to find visually a clearing in the hash of all AM and CW emitters spread on a band.

The Panoramic Radio PCA-2 T-200 Panadaptor sold in 1946 by Hallicrafters as the SP-44 Skyrider Panoramic. At right the cover issue of March 1948 issue of Radio News featuring the Panadaptor used during the Gatti-Hallicrafters Expedition in South Africa. Documents K4XL and Antique Radio.

This technology was not really recognized until 1936, when QST magazine recognized that the "cathode ray tube", the oscilloscope, made an excellent tuning indicator for the receiver. The first article about panoramic adapter was published in 1942 but very few hams had the opportunity to read it. In this article Hallicrafters announced the release of the first panoramic receiver "when short wave equipment [will be] again available for civilian use". Eventually, the peripheral named Skyriger Panoramic SP-44 will be released end 1946. Immediately after, QST and Radio News described the vital role that panoramic reception had during the war to visually monitoring frequencies used by both Allied and enemy troops to coordinate operations. 

At that time, the SP-44 Panadaptor cost $99.75 (over $900 of 2004) and could operate in a bandwidth over 200 kc for an IF near 455 kHz.

The Icom IC-756 Pro II built-in band scope.

In the '60s, its competitors began marketing their own version of the Panadaptor : Radiophone Band Scanner Model 44 in 1962, Heathkit Ham Scan HO-12 Spectrum Monitor in 1964 followed by Squires-Saunders SS-1V Video Bandscanner. 

More than 70 years after this discovery, no more electronics firms manufacture such devices for amateur activities. The most recent where built in the '70s and '80s and are no more manufactured : the famous Kenwood SM-220 Monitor scope, Sherwood Communications SCA-7000 Signal monitor and Yaesu YO-901 Multiscope

Today amateurs take advantage of more versatile solutions like software interfaces. At last some clever manufacturers like Icom, Tec-Tec or Yaesu/Vertex have included a band scope in their more recent HF transceivers.

Birth of SSB

In its issue of September-October 1933, the small Los Angeles R/9 magazine published a three-part article entitled "Single Sideband Transmission for Amateur Radiophones" written by Robert M. Moore, W6DEI. It reported an experiment using no more AM mode for communication but a "single-side-band, suppressing carrier" mode, SSSC. The article didn't generate much enthusiasm and although amateurs understand well what could be the benefit of suppressing this carrier, this concept was not associated yet to receiver or transmitter able to support this mode. 

In was a fact that in using the AM, all amateurs experimented interference causes by the frequency-hogging of this mode. Amateurs bands became a mess and a new technology step had to be made. However, the SSB as it will be called had to wait until 1947 to benefit of a more fertile ground to develop.

First International Field Day

In its June 1933 issue, QST magazine announced the start of the first International Field Day activity. The event should last 27 hours beginning the second Saturday at 4 PM local time (there was no daylight savings yet !). The author, F.E. Handy, W1BDI told to conclude his annoucement, "the real object of this contest is to test 'portables' wherever they may be available. If successful, we want to make it an annual affair". The RSGB, NVIR and RB sponsored similar national Field Days in Europe. To score the event, each QSO worked with a fixed station counted 1 point, contacts with other portables counted 2 points, and DX contacts counted 3 points. Multiply QSO points by the total number of ARRL sections, plus countries worked. The winner of this contest was a non-club group signing W4PAW. Club members made 62 QSOs.

1933 Field Day at W0AR.

For the second Field Day of 1934, the multiplier for sections and countries was removed, emphasing to the total number of stations contacted. At this point, multi-band contacts were not permitted. DX contacts, while still allowed, received no special point advantage. The scoring system began to ressemble Field Day as we now know it, with 3-, 2-, or 1-point multiplier per QSO depending on power ouput. But in the '30s, the breakpoints were set at 20 W and 60 W !

This is in 1937 that the "Field Day message" was born. This bonus gave 10 points (before multiplier) and was awarded for a single properly formed and serviced message to League HQ stating the number of ops, location, "conditions", and power. 

For the first time, the winning QSO total reached 204, with a breathtaking average rate of 7.5 QSOs per hour. Today copying the ARRL's W1AW message is worth 100 points.

This is in 1940 that modern rules emerged, including contacts on multi-bands, 25 points for Field Day messages, and a 500-feet radius for all equipment what gave multi-transmitter teams a little breathing room. In 50 years the rules changed not less than 12 times, mainly the points assigned to message or the one associated to CW and SSB contacts !

Note at last that in 1941 a VHF-only category was introduced and in 1949 the first Field Day Mobile came to age. In 1975, to avoid the supremacy of SSB, the 2X rule for CW QSOs was introduced. In 1976 while amateurs celebrated the Bicentennial, W1VV/1 celebrated its 10,010 QSOs ! In doing so, the group surpassed the 1933 QSO record in its first 15 minutes of operation !

Today most national IARU societies organise their own Field Day that is usually accessible to all categories of amateurs. Some contesters work QRP with 5 or 10 W output while others work only on VHF, by satellite, powered by battery or even natural power source (e.g. using a bike if a muscled OM is supplied, HI !). In all categories the Field Day stays an event very appreciated by both novices and advanced amateurs. For the contester working in the field in the shadow of a tree this is always a moment of freedom and pleasure. Even SWL are happy as they can easily hear more than a hundred of countries in a weekend.

Just after war Amphenol published the first advertisments for coaxial cable in the December 1945 issue of QST.

First experimental coaxial cable

On December 8, 1931 Lloyd Espenschied and H.A. Affel from AT&T received their first US patent No. 1,835,031 for their "concentric conducting system", aka the coaxial cable (invented by Oliver Heaviside in 1880).

Their project was not intended for amateur transmissions but rather for the first television signals that required a line broadband enough to transmit a range of frequencies compatible with television image. Espenschied and Affel's invention involved placing a central conductor inside a hollow tube and holding it in place with washers spaced equally along the length of the tube. The low-loss dielectric was air.

In 1936, only 200 TV sets were in use worldwide, some using a tilted mirror to reflect the cathodic image to the viewer or directly a straight or vertical screen. At the beginning, telephone (voice) and TV signals, analog, were carried on paired wires (cable or open wire) but quickly, it appeared that the number of voice channels could be improved. The same year AT&T, pioneer in many areas of electricity and electronic, laid his first experimental coaxial cable between New York and Philadelphia.

 In 1938, the "British Admiraly Handbook of Wireless Telegraphy" (section R37-38) went on to say about the coaxial : "It appears possible that this type of cable may find an increasing number of uses. it could be used very conveniently as a transmission line joining a high-frequency aerial system to its receiver". It was at this time that the coax acquired its RG/U (Radio Guide Utility) numbers.

Coaxial cable is called "coaxial" because it includes one physical wire or channel that carries the signal surrounded, after a layer of insulation made of a solid or air spaced dielectric, by another concentric physical braid, both running along the same axis. The external braid serves as a ground. It is protected with either a aluminium sheet or directly with a more or less thick rubber sheath.

Different types of coaxial cables.

The coaxial cable is till used by amateurs or sometimes by professionals in the field. Th coax is twice to three times more expensive than the simple electric wire (about 60 € for a 100 m roll of RG-58). However it is much more resistant and offer some protection against RFI.

The first regular coaxial installations began in 1941 with RG-58/U that linked Minneapolis to Stevens Point, WI. At that time the original "L1" coaxial-cable system had 4 pairs or channels of coaxial tubes in one cable sheath, including backup protection channels. Each channel could carry 600 voice circuits for a total route capacity of 2400 communicaton lines. 

In practice, the L1 coax could carry 480 telephone conversations or one television program. Thirty years later the new types of coax carried more than 132,000 calls !

If coaxial cables like RG-58,  RG-213 or L1 are till occasionally used to transmit television, telephone and data signals, public infrastructures including Internet lines, and most entreprises have today replaced these low speed lines by fiber optic much more performing. Only a very short segment going from the computer, the TV or the transceiver to the controller (switch or router), the decoder or to the antenna uses a copper wire. But even in these configurations, we can sometimes replace the copper line with a Wi-Fi or a fiber optic connexion.

The King of Drama at work at CBS.

The War of Worlds

In 1938, many people living on the Eastern Coast of the U.S.A. heard on CBS radio that a "War of the Worlds" had started. The reporter, a certain Orson Welles, told that "Our civilization is going to be destroyed again by animal-like creatures which landed here from the planet Mars...". The drama scared all a nation at such a point that FCC had to "investigate the discs embodying the electrical transcription of the startling realistic broadcast" wrote the Trenton Evening Times gazette on November 1st, 1938. Here is an extract of the 1953 film.

In fact, the audience was not  used to this new medium yet, and few people were informed about new technologies, hence the panic that invaded New York and New Jersey... It was already a master stroke from the King of drama, and a huge publicity for CBS and all radio broadcasters. Now people knew the power of media !

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Birth of Radioastronomy

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