Radio Anniversaries Abound in December

December is the month in which three notable events in radio history occurred — the first radio transmission heard across the Atlantic Ocean in 1901, the first broadcast of the human voice and music in 1906, and the first successful transatlantic Amateur Radio HF transmissions in 1921.

Marconi’s 1901 Transatlantic Transmission

On December 12, 1901, Italian wireless pioneer Guglielmo Marconi succeeded in receiving the first transatlantic radio signal, transmitted from Poldhu, in Cornwall, England, to St. John’s, Newfoundland, Canada. Marconi’s team in Cornwall transmitted the letter “S” in Morse code, and this was heard by Marconi and his assistant George Kemp at a facility set up in Cabot Tower on Signal Hill in St. John’s. On the Cornwall side, Marconi had erected a powerful spark-gap transmitter feeding a massive antenna. The receiving team used a kite antenna. The experiment proved that radio signals could be transmitted beyond the line of sight, opening the door to global wireless communication.

An article in the December 2007 issue of QST suggested that absorption may have been less in 1901 than in the 21st century, perhaps contributing to the success of the feat, which occurred during daylight on the Canadian end.

Fessenden’s 1906 Broadcast from Brant Rock

On Christmas Eve 1906, experimenter Reginald Fessenden made what may have been the first radio broadcast to include speech and music. The transmission originated at Brant Rock, Massachusetts, about 30 miles from Boston.

As he’s done in year’s past, Brian Justin, WA1ZMS, of Forest, Virginia, will commemorate that first audio broadcast by operating WI2XLQ on 486 kHz this month, marking the 111th anniversary of the Fessenden’s accomplishment. Historic accounts say Fessenden played the violin — or a recording of violin music — and read a brief Bible verse, astounding radio experimenters and shipboard operators who heard the broadcast.

“Since we now have a ham band on 630 meters, I will have a shorter transmission period this year that will only cover the Christmas holiday,” Justin told ARRL. That’s because he hopes to be active on the new band himself.

Justin will begin his transmission on December 24 at 1700 UTC and continue until December 26 at 1659 UTC. For his transmitter in 1906, Fessenden used an ac alternator modulated by placing carbon microphones in series with the antenna feed line. Justin’s homebuilt station is slightly more modern, based on a 1921 vacuum tube master oscillator power amplifier (MOPA) design, using a UV-202 tube. The transmitter employs Heising AM modulation, developed by Raymond Heising during World War I.

Send listener reports directly to Brian Justin, WA1ZMS.

The ARRL Transatlantic Tests Revisited

In 1921, ARRL sponsored two series of transatlantic tests to see if signals from previously qualified Amateur Radio stations could be heard at a receiving station in Ardrossan, Scotland. The second series succeeded, with several ham stations heard on the receiving end, using equipment far superior to what had been available to Marconi just 20 years earlier. “The Story of the Transatlantics” chronicled the events in the February 1922 issue of QST, to great fanfare. As Mike Marinaro, WN1M, recounted in “The Transatlantic Tests,” in May 2014 QST, the first signal “unofficially” heard in Scotland was actually that of a pirate, identifying as 1AW and not using the prearranged transmission format.

The “rough listening post” in Scotland, staffed by receiver designer Paul Godley and D.E. Pearson of the Marconi Company, was equipped with a superheterodyne and regenerative receiver connected to a 1,300-foot Beverage antenna, 12 feet above ground.

On December 10, the CW signals of official entry 1BCG, owned by Minton Cronkhite, “were solidly heard on 230 to 235 meters,” Marinaro wrote in 2014. “This signal derived from the specially designed and constructed station of the Radio Club of America at Greenwich, Connecticut — the only station heard that morning.”

Connecticut radio amateur and radio history buff Clark Burgard, N1BCG, will be among those celebrating the 96th anniversary of the first transatlantic shortwave transmission in Greenwich, Connecticut. Several other stations will take part by establishing contacts between the US and Europe, including GM7VSB in Ardrossan, Scotland.

No specific bands and frequencies were set in advance, in order to “permit flexibility due to propagation.” Burgard has posted additional information on his QRZ.com profile page.

Chris Codella, W2PA, provides additional radio history on his “Ham Radio History” website.

Source:ARRL