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The History of Amateur Radio

American amateur Raymond H. Williamson, 9AHH, in 1921. This picture shows him at 14-year old working in CW. He was already a DX hunter.

Ham, the poor operator (IV)

Any amateur radio wonders one or another day what could be the origin of the word "ham". There are at least three possible origins. 

The first "legend", because never confirmed, tells that the word was given in G. M. Dodge's The Telegraph Instructor in the XIXth century, even before radio. The first wireless operators were landline telegraphers who left their offices to go to sea or to man the coastal stations. They worked in "plain text", bringing with them much of the tradition of their older profession, including jargon.

Using spark transmitter, each spark occupied the whole spectrum or almost. If stations were too close each another this caused jam and nobody could receive any message. Government stations were concerned with this QRM but also ships, coastal stations and of course the increasing number of amateur operators; all competed for time and signal supremacy in each other's receivers. 

Among these amateurs, some stations emitted with 2 kW and, like today, some of them jammed all the other operations to a few hundred kilometers around. When this occured, frustrated commercial operators would call the ship whose weaker signals had been blotted out by amateurs and keyed back : "SRI OM THOSE B@$%#! HAMS ARE JAMMING YOU". Amateurs, possibly unfamiliar with the real meaning of the term, picked it up and applied it to themselves and wore it with pride as a word qualifying their activity... As the years advanced, the original meaning has completely disappeared.

The second version tells that it is maybe in 1910 that the word was invented. Before the callsigns where regulated a powerful station able to emit at 5 kW and that everybody could hear at all hours of the day and night at distances of over 800 km (500 miles) operated with the initials H.A.M. No one knows if this rumor is true or false. 

The last version tells that the word "ham" was invented in 1933 for a publication dealing with amateur radio. But I have no more detail. In my humble opinion if the HAM station existed there would have had archives about it, but there are none. The first and the third "legends" are both likely but are not confirmed. In all cases "ham" became synonymous of amateur radio.

Guglielmo Marconi in 1908. Document LOC corrected by the author.

In 1911, Modern Electrics printed 52,000 copies of his magazine. There were 10,000 amateurs in the USA, as many or almost in the United Kingdom and probably as many in gathering all other countries together.

With tens of thousands of stations on the air, both amateurs and commercials, the level of interference became a serious problem, especially in marine communication. Due to their poor efficiency, it was not unusual that one spark amateur station transmits over a broad spectrum exceeding 100 or even 300 Kc, depending on its coil diameter and output power ! 

Ships, because of their restricted antenna length were lost in this QRM and experimented difficulties to establish routine communications when other stations, more powerful, were transmitting. There was also deliberate interference created by commercial stations jamming voluntarily the transmissions of other companies. At last the US Navy used inefficient and outmoded equipment and suffered much from excessive interference. Due to all these complains, the U.S. Congress took a serious look at wireless regulation. But wait a moment, I have just received a wireless message that will, I sense, dramatically alter the future of the wireless communications.

1910 : Birth of the first Wireless Club

This is 1910 that was founded the first national radio society in the world, The Wireless Institute of Australia (WIA). It was quickly followed in the spring of 1911 by the foundation of the first Wireless Club of Great Britain in Derby, near London. J. Parsons acted as the first Secretary and the station callsign was QIX. Quickly books were purchased and a lending library started. The Club gave valuable advice to other amateurs fan of wireless and on August 12, 1912 the Amateur Radio Movement was officially recognised in the U.S.A.

The second organization was the London Wireless Club that was formed on July 5, 1913 and renamed the Wireless Society of London on October 10th. Its first president was A.Campbell-Swinton until 1920. The Club kept its name until 1922 when it became the famous Radio Society of Great Britain (RSGB).

1912 : The Titanic Tragedy

On Monday, April 15, 1912, at 12:30 AM, in the middle of the night, the R.M.S. Titanic struck an iceberg in the North Atlantic near Canada and sank at 41░46' N, and 50░14' West. Thanks to wireless, and the first S.O.S. in history, 745 passengers were saved but 1595 persons died in this accident among them some of the most prominent persons in the world. 

An operator at Marconi House in 1912.

Behind this disastrer, it has been argued that the number of survivors could have been doubled or even tripled, if there were stronger wireless regulations in effect.

Indeed at least three problems appeared and increased the slow response of rescuers. First, the radio operators were only on duty during the "open hours", thus only at daytime. Any event could thus occured at night without warning.

Then, in 1905, the Morse code "SOS" (that does not mean Save Our Souls but became de facto) was adopted by German ships for signifying distress while the British marine, working with Marconi operators, wanted to keep CQD (General Call Disaster that some translated by Come Quick Disaster) as a distress signal.

Marcon had first decided to use SOE, but the small "E" dot could easily be lost in QRM and one suggested to replace it with an S, as in repeating three time the small tune the operators had much more chance to arrest the attention of anyone hearing it, hence SOS, that  was adopted at the Berlin Radiotelegraphic Convention in 1906 as the official international standard for distress calls. But Marconi operators were slow to conform, and until 1907 Marconi companies continued to work with the "CQD", associated, if necessary, to SOS.

At last, there was a commercial war between Marconi and his German competitor, Telefunken, that extended down to the individual radio operators. In these early days of telegraphy, where the Stock exchange was growing fast and gave the chance to small like major companies to increase their benefits, the smallest part of a market took at the competitor meant a probable increasing of shares price at short time. This is this context of commercial war that no routine traffic, even in an emergency, would ever pass from a Marconi station to his competitor. This arrived at such a point that when a "Marconist" was on the air, the others would be shut out, and often, the rules was respected.

This story is interesting to remind because it emphasizes the problem of security aboard the ship, and the lack of a standard wireless regulation. Instead of developing this long affair below, I suggest you to read the dedicated page that I wrote about this tragedy and the behaviour of Marconists. Then don't forget to come back to know the consequences of this affair.

To read : The Titanic Tragedy, sunk between CQD and SOS

CQD CQD SOS Titanic Position 41.44 N  50.24 W... SINKING...

The Titanic before, during and after the accident. The center image is fake. The image of the shipwreck was taken by Dr. Robert Ballard in 1985. It was taken by 3780 m (12600 ft) deep. The expedition to RMS Titanic was set out on July 5, 1985 including scientists from IFREMER (Institut Franšais de Recherches pour l'Exploration des Mers) and WHOI (Woods Hole Oceanographic Institution). You will find more images and data on WebTitanic. Here is a reconstitution I made of one of the distress calls sent in CW at 40 WPM (CQD CQD SOS MGY requir imediat asistanc position 41.46 N 50.14 W...).

The Radio Act of 1912

On May 18, 1912, Senator Smith introduced a bill in the Senate. Among its provisions (rather long) note a recommendation or rather a "command" for more security on ships, obliging for example maritime companies to engage up to three wireless operators per ship to ensure a 24-hour duty, a decision that was fully justified. To avoid "ownership" of the spectrum by the Marconi Company, Senator Smith wanted that licenses be now required, issued by the Secretary of Commerce. Each Government (Police, Forest, etc), Marine, or Commercial station would be authorized a specific wavelength, power level, and hours of operation. The initial legislation had considered the elimination of all private, non commercial stations, thus including amateurs. 

At the first reading the Congress realized that it would be hard and expensive to verify its application.

An anonymous spark gap US hamshack starring a huge HV helical transmitting inductor. Take care OM, it's HV !

Since it was a "well known fact" that long wavelengths were the best to work, and that anything below 250 meters was considered "useless" except for local communication, a compromise was found. Amateurs received the 200-meter band and below (1.5 Mc and up), where they could work 40 km (25 miles) maximum. In fact Senator Smith thought that amateurs would die out in a few years by lack of means and support.

In retrospect the Government thought that the only really useful frequencies for long distance communication were the very low frequencies between 100-1000 Kc (3000-300 meters). Thus, this regulation offered to the ham community an apple for the thirst but not really a bandplan suited for experimentation, and their survive seemed to be a question of time. This is thus under these conditions edicted by a state monopoly and without dialogue that amateurs were relegated to the wavelengths of 200 meters and below (1.5 Mc and up), the equivalent of all the spectrum above roughly the AM broadcast band, generally thought useless for DX communications. In the new law administered by the Secretary of Commerce, amateurs considered as "private stations" were also limited to a maximum power of 1 kW.

At first, it appeared unfortunately that bureaucrats were correct. Before the Radio Act, there were an estimated 10,000 US amateur stations and still a handful outside the U.S.A. Now, there were only 1200 licenses issued by the end of 1912. Amateurs encountered difficulties to get their spark stations going on 200 meters, and, when they did, they discovered their maximum range was 40-80 km (25-50 miles) what reduced by ten the range they had on the shorter frequencies ! It seemed that there was no future for amateur radio. But "the air" doesn't make the song...

Fleming's vacuum diode, 1908.

Lee de Forest's triode vs. the King Spark

Hams had difficulties to get effective communications on 200 meters (and in fact on any wavelength) because the spark transmitter and the unamplified receiver were both extremely inefficient. There was well some shy development in the vacuum tube area but these devices cost a lot of money, they provided quasi no amplification, and were power hungry. 

In 1908, after have invented the vacuum diode like the funny but operational one displayed at right, the Englishman J.A. Fleming developed the first triode but the device was not very efficient and expensive. Spark gap transmitters and crystal receivers reigned on the air until 1912, when a 22-year old amateur made an important discovery.

A thermionic triode or "button tube" switched on and standing on a superb blue socket. It was built by H.P.Friedrichs, AC7ZL, from the idea of Lee de Forest's Audion.

The american electrical engineer Edwin H. Armstrong bought a Lee de Forest's Audion of Old for his receiver. Unsatisfied with the poor amplification, he changed the circuit and "fed back" a portion of the output signal back to the input to get a re-amplification. Thanks to this stratagem he got an amplification factor 100 times stronger than the input ! Better, when there was much feedback, the tube began to oscillate, and thus generated stable RF.

This discovery permitted amateurs to use vacuum tubes offering a gain of 2000 times and more ! This solution placed immediately the "old" spark design to the back stage. Now a broad inefficient signal that took hundreds of Kc of bandpass, oscillated on a stable and pure frequency thanks to the modified Audion. The signal was so pure than a continuous wave could be emitted on one frequency rather than a broad and intermittent wave on almost all the spectrum. The "C.W." acronym was born and with it this revolutionary discovery revitalized the Phoenix; radio amateurs could survive and even grow !

Although Armstrong took more than 10 years to develop the stability of both transmitters and receivers for CW, realizing the importance of his "regenerative" design, but short of money to develop its invention, in January 1913 he took the wise decision to notarise his circuit.

In 1913, Lee de Forest improved the triode invented by R.von Lieben using a positive feedback, and quickly after AT&T developed the first vacuum tube repeaters for its new telephony network. But these triodes offered a low gain, about 20 times, and had unsollicited capacity.

To get greater amplification, additional grids were added to these tubes. Tetrodes come with 2 grids, the 2d being called the "screen" grid because it screens, or isolate, the control grid from the plate. Tetrodes produce output signals about 600 times greater than input, and pentodes, constituted of 3 grids, amplify the signal about 1500 times ! This time Lee de Forest's triode detroned the King Spark !

Next chapter

The first radio prefixes

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