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Making the Most of Useless Frequencies

useless frequencies

Ham radio is about making the most of useless frequencies. And supporting scientific discovery along the way. 

Paul Godley went on a long trip in December1921. This New Jersey ham was sent to Ardrossan, Scotland to conduct an experiment. Could shortwave radio signals cross the Atlantic? It was time to find out.

Along the rain swept shore of the Firth of Clyde, Paul set up his receiving station in a tent. He also erected an 850 foot long Beverage antenna. And, at 2:52 a.m. on December 21, he heard a radio message from Greenwich, Connecticut.

Perhaps you thought Marconi had received the first transatlantic message. Not so. In December 1901 – twenty years earlier – Marconi received a transatlantic signal. The radio era began. But there are two problems with the Marconi story.

  • Firstly, Marconi heard a signal not a message. The signal received by Marconi in Newfoundland was the Morse code letter “S” – three dots. That’s all. Given the equipment of the time, it would be hard to distinguish the signal from static noise. Godley received and decoded an actual message of fourteen words.
  • Secondly, given the frequencies Marconi used, it is unlikely that a radio signal actually crossed the Atlantic. In fact, no one actually knows what frequency Marconi used, not even him. Measuring and controlling frequencies accurately was not possible at the time. Probably it was somewhere between 100 and 800 kHz.

Nevertheless, radio blossomed and bands got crowded in the decade after Marconi’s achievement. In 1912, the U.S. government banned all private (amateur) radio transmissions to frequencies above 200 meters. These were seen as useless for commercial activity.

Useless Frequencies? Not really

Signals below 200 meters are long wave. They travel almost exclusively as waves hugging the earth. Signals higher than this have far less ground wave coverage, if any. Scientists declared that frequencies above 1500 kHz could not support long distance communication.

But, as early hams experimented with higher (shortwave) frequencies, they discovered a different mode called sky waves. Somehow signals traveled also through the sky, and could go great distances. This is what Paul Godley proved in 1921.

Within five years, surprised scientists discovered the ionosphere. So, the message here is that science is never settled.

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