October 1997- Pages 6 & 7
Bill Continelli Presents
THE WAYBACK MACHINE
entered the summer of 1912 with a new Radio Act in
place.Thanks to the Titanic disaster and the fear that
commercial interests would try to monopolize the radio
spectrum, the government stepped in and set up a
licensing structure administered by the Secretary of
Commerce. In the new law, amateurs (actually
"private stations") were limited to a
wavelength of 200 meters and a maximum power of 1 kW.
Since the known usable spectrum at that time ran from
about 300 to 3000 meters (1000 kHz to 100 kHz), it was
widely believed that amateur radio would fade away,
without expensive government enforcement.
At first, it appeared that the bureaucrats were correct. Before the Radio Act, there were an estimated 10,000 stations. Now, there were only 1200 licenses issued by the end of 1912. Amateurs were finding it difficult to get their spark stations going on 200 meters, and, when they did, they discovered their maximum range was 25-50 miles, instead of the 250-500 mile range they had on the longer wavelengths. Amateur radio was slowly heading for oblivion.
The big stumbling block to effective communications on 200 meters (or indeed any wavelength) was the spark transmitter and unamplified detector, both of which were extremely inefficient. On the transmitting end, no method, other than spark, was known. As for the receiver, there had been two developments in the vacuum tube area. J.A. Fleming had developed the diode detector in 1904. It cost a lot of money, provided no amplification, and used expensive batteries. It was not practical at the time, but it was covered by a patent. In 1906, Lee de Forest took Fleming's valve, added a third element, called a grid, and named the result the Audion. In the right circuit, the Audion could amplify by a factor of 5x. Still, because of the cost, battery requirement, and the ever popular patent fights of the time, it went unnoticed and unused until 1912, when a 22 year old amateur made an important discovery.
Edwin H. Armstrong was an experimenter and almost militant individualist. He had obtained an Audion for use in his station. Dissatisfied with the poor amplification, he tried different circuits. At one point, he "fed back" a portion of the output back to the input to be re-amplified. Instead of just a 5x amplification, the output was now 100x stronger than the input. He also discovered that if too much feedback was used, the tube began to oscillate. This regenerative circuit was the most important discovery in radio in years. One tube could amplify more than 100x, two tubes in series could give a gain of 2000+. In addition, an alternative to spark was now available. Instead of a raspy, broad, inefficient signal that took
up hundreds of kHz, the Audion could be made to oscillate a stable, pure signal on one frequency. In fact, that's where the abbreviation "CW" comes from, (a Continuous Wave on one frequency rather than a broad, intermittent wave on many). Although it would take 10+ years to develop the stability in transmitters and receivers to fully utilize CW, King Spark was doomed.
Realizing the importance of his regenerative design in both transmitting and receiving, but lacking the money to develop it, in January 1913 Armstrong had the diagrams of his circuit notarized. This was only the first of many spectacular inventions Armstrong would come up with. Within 10 years, he would also develop the superheterodyne (now used in ALL receivers), and the super regenerative (the basis of all VHF and UHF receivers from the 20's to the 50's, and still used today in children's walkie-talkies). Even his first design, the regenerative circuit, is used by Ten-Tec and MFJ in their receiver kits. The crowning achievement in Armstrong's career came in the 30's, when he developed Frequency Modulation. With all due respect for those who flock to Loomis, Tesla, or Marconi as the father of radio, my vote goes to Armstrong, for without him, wireless would be stuck at the 1912 level. Armstrong had a tempestuous life, full of public and private battles, advancements, setbacks, and lawsuits, before his tragic death in 1954. The final legal battles didn't end until 1967. ("The Wayback Machine" will devote an entire column to Armstrong in a future edition.)
Meanwhile, back in 1913, word of the regenerative circuit spread quickly throughout the amateur world. Experimenters who added the Audion to their receivers discovered that distances of up to 350 miles were now possible on 200 meters. The Audion, already scarce and expensive, became even more so under the laws of supply and demand. The search for an Audion to the amateur was like the Quest for the Holy Grail. In fact, it was this search which led to the second pivotal event in amateur radio history.
Hiram Percy Maxim was a 44 year old engineer and inventor who had a 1 kW amateur station in Hartford, Connecticut. He wanted an Audion for his receiver and was unable to locate one. Finally, he heard of an amateur in Springfield, MA, who had one for sale. Hartford was (and still is) only 30 miles from Springfield, yet Maxim's station could not cover the distance. He found a station midway between the two cities that was willing to relay his purchase offer.
Maxim thought about this and eventually realized that a national organization was needed to coordinate and standardize message relay procedures, as well as act as a national lobby for amateur radio interests. On April 6, 1914, Maxim proposed the formation of the American Radio Relay League. With the backing of the Radio Club of Hartford, who appropriated $50 and some volunteers, Maxim developed an application form explaining the purpose of the ARRL and inviting membership. These were sent out to every known major station in the country.
Maxim, like Armstrong, was a prolific inventor. Unlike Armstrong, however, Maxim was also an expert in publicity and public relations. By July, national magazines such as Popular Mechanics were writing favorable reports about the ARRL. Maxim also traveled to Washington, DC, to explain the ARRL to the Department of Commerce and the Commissioner of Navigation.
The P.R. blitz paid off. By September, 1914, there were 237 relay stations appointed, and traffic routes were established from Maine to Minneapolis and Seattle to Idaho. Realizing that long distances on 200 meters were not possible at that time, even with a regenerative receiver, Maxim got the Department of Commerce to authorize special operations on 425 meters (706kHz) for relay stations in remote areas.
Boosted by the publicity, the number of amateur stations, as well as the relay stations in the ARRL, continued to grow. By 1916, there were 6000 amateur licenses, (of which 1000 were ARRL relay stations) and 150,000 receivers in use. The emphasis in the ARRL was on the word RELAY; ARRLstations were expected to handle traffic on the 6 Main Trunk Lines (3 North/South and 3 East/West) that served more than 150 cities. And there was traffic. The general population (to whom phones were a luxury, long distance an exotic concept, and telegrams expensive) flocked to the idea of coast to coast free messages. As a P.R. exercise to test the system nationwide, on Washington's Birthday, 1916, a test message was sent to the Governors of every State, and President Woodrow Wilson in Washington, DC. The message was delivered to 34 States and the President within 60 minutes. By 1917, the system was so refined that a message sent from New York to California took only 45 minutes. To deal with the increasing number of relay stations, the ARRL started a little magazine, which they called QST.
Other amateur activities in this period brought favorable publicity to the hobby. In March 1913, a severe windstorm had knocked out power, telegraph and telephone lines in the midwest. Battery powered amateur stations handled routine and emergency traffic until regular service was restored. This was the first documented emergency communications in amateur radio history. In 1915, amateur station 2MN determined that the powerful Telefunken station (see August 1996 issue of "Popular Communications" magazine) at Sayville, Long Island, was sending information concerning Allied and neutral shipping to submarines at sea. Thanks to the work of this amateur, the government took over the station.
However, the war in Europe was getting closer. In April, 1917, based on continued violations of our neutrality and unrestricted submarine activity, Congress declared war against Germany.
With the US now in World War I, a message went out from the Secretary of Commerce to all private stations. By order of the Chief Radio Inspector, all transmitting AND RECEIVING stations were to be closed AND DISASSEMBLED, and all antennas taken down. Complete radio silence was to remain until the war ended and the order was revoked. Amateurs by the thousands packed away their stations and marched off to war. The 200 meter band was silent. In September 1917, with no radio activity permitted and 80% of the amateurs at war, QST ceased publication.
Would amateur radio survive the war? Join us next time as "The Wayback Machine" waits for Johnny ham to come marching home again.
Written By: Bill Continelli, W2XOY
What's New at the TARA BOOKSTORE
Introducing the New
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