“The heroism and grit of our warriors leave no doubt that Ukraine will prevail,” said the President of Ukraine, Volodymyr Zelensky, in a stirring speech broadcast on his government’s YouTube channel. Ukraine is fighting two battles – one against a physical army and another against disinformation. One weapon in its arsenal that is helping it do both may be surprising: short-wave radio.
This legacy technology is an old version of AM analogue radio that operates on low-frequency radio waves. It is used to transmit audio signals over long distances by bouncing them off layers of charged particles in the Earth’s ionosphere, which is part of the upper atmosphere between 80 and 600km above sea level.
Used by spies in the Cold War, short-wave radio is less complicated than newer communications options. It is still used in remote parts of the world where local broadcasting is not accessible, as well as in occupied and war-torn countries such as Ukraine. In these...