Bouncing Beyond Borders: The Reach of Shortwave Radio

By Pavek Museum Curator Dr. Luis Felipe Eguiarte Souza
Edited by Kaeleen Laird

Have you heard of shortwave radio? Spanning the 2-30 MHz wireless frequencies, shortwave has been part of radio history since its infancy with Guglielmo Marconi in the 1920s. Shortwave can bounce signals off the ionosphere, allowing it to travel around the globe, crossing borders, and granting international broadcasters to reach a global audience. Popular listenership peaked in the 1930s when commercial broadcasters tried their luck in this radio band. Shortwave was also prominent in the Cold War (1945 to 1991) when different nations produced their own radio stations to broadcast their political ideologies and affiliations.

International shortwave radio stations always need listeners to report back about the strength of their signal. As shortwaves bounce off the horizon, they can be affected by weather conditions, the time of day (and season of the year), and sunspot activity. Communications receivers and long antennas are required to listen to shortwave signals, which can suffer from considerable fading, distortion, and static. So, listening to shortwave can be as much an art as it is a science.

Shortwave radio started one of the most important traditions held in the UK, the Christmas Message, where the King or Queen will send holiday good wishes through a form of electronic communication. The idea for a Christmas message from the sovereign to the subjects of the British Empire was first proposed by the founding director-general of the British Broadcasting Corporation (BBC), John Reith, in 1922. But King George V declined, believing that radio was mainly a form of entertainment and a passing fad. Ten years later, Reith approached the King again in 1932 to inaugurate the BBC’s Empire Service (now the World Service), King George V read the first Royal Christmas message. This broadcast reached an estimated 20 million people in Australia, Canada, India, Kenya, South Africa, and the United Kingdom.

One of the more mysterious aspects of shortwave radio is Numbers Stations, which are characterized by broadcasts of formatted numbers commonly believed to address intelligence officers operating in foreign countries. The idea is that the message would be encoded in a series of numbers. For example, using what is known as a one-time pad (OTP), an encryption technique that cannot be cracked but requires using a single-use pre-shared key that is larger than or equal to the size of the message being sent. Most Numbers Stations have set time schedules or patterns, but others have no discernible pattern and broadcast at random times. Numbers Stations have been reported since at least the start of World War I and continue to be used today. Amateur radio enthusiasts are interested in monitoring and classifying Numbers Stations, and many are given nicknames to represent their quirks or origins.

The United States has its own shortwave radio station called the Voice of America (VOA). VOA was created in 1942 to spread propaganda during World War II. In contrast to its predecessors, the National Broadcast Company International Network or the Columbia Broadcast System, the VOA is a state-owned news network and international radio broadcaster. VOA produces digital, T.V., and radio content in 49 languages, which it distributes to affiliate stations around the world. Its targeted and primary audience is non-American. It is headquartered in Washington, D.C., and overseen by the U.S. Agency for Global Media (USAGM), a nonpartisan agency of the U.S. government.

Other countries, like Mexico, also have their own shortwave radio stations. Radio México Internacional is a Mexican government-run radio service based in Mexico City. State-operated shortwave broadcasting in Mexico dates back to at least 1934 with XECR. In 1968, then Secretary of the Interior, future President Luis Echeverría, ordered the creation of a new shortwave station. XERMX-OC (Radio México Internacional) began broadcasting on September 1, 1969. Since 1983, it has been under the control of the Instituto Mexicano de la Radio (IMER), which is very similar to National Public Radio (NPR) in the U.S. The cost of operation and the lack of listeners made IMER Director Dolores Beistegui decide to shut down the station in 2004. In 2011, IMER relaunched it as an Internet radio service. It provides programming in Spanish, English, French, and indigenous languages, with programs including music, dramas, and documentaries.

Shortwave radio programming can become an act of bravery. On the night of June 3rd, 1989, in Beijing, China, a student-led demonstration asking for political reform that had been going on for months was violently repressed in what is now referred to as the Tiananmen Square massacre.

During the protests, a courageous announcer at Radio Beijing, now known as China Radio International (CRI), the state-owned international radio broadcaster founded on December 3rd, 1941, as Radio Peking, decried the government’s crimes against the students and asked the international community not to forget their sacrifices. According to some sources, the announcer was apprehended by the authorities almost immediately after the transmission and detained for several years in a re-education camp.

Although Internet radio services have replaced shortwave in a lot of places, it is still used today by amateur operators around the world. These frequencies still play an important role during disasters, as they can reach farther and cross borders; as such, we recognize the important history of this genuinely global-spanning form of electronic communication.