More than a decade ago, pop singer Sheryl Crow proclaimed "I don't have digital, I don't have diddly-squat" in "Soak Up the Sun," her ode to happiness and vitamin D absorption.
By today's standards, everyone has digital, even traditional shortwave broadcasters like Voice of America - a respected source of information since 1942 with an annual multimedia budget of more than $200 million.
While AM shortwave transmissions are relics of an earlier time, VOA is experimenting with digital-only broadcasts in its "VOA Radiogram" on select HF frequencies on weekends. When decoded with software, VOA Radiogram produces text and decent quality pictures that are more impervious to interference and jamming than voice.
Shown below are two examples of images downloaded by listeners the weekend of July 2-3, 2016:
(Photos used courtesy of VOA Radiogram and Twitter.com.)
"Shortwave can be used to transmit text and images in situations where the Internet is disrupted because of censorship or disasters, or unavailable because of remote location," Radiogram director Kim Andrew Elliot tells Squelchtale.com. "Our experiments with text via shortwave have demonstrated resistance to jamming on shortwave."
Dr. Elliot says almost any shortwave radio can be used, but it's preferable to have one with sideband capability. The audio is connected to the sound input of the computer, and software like Fldigi converts it to text and pictures on the screen.Fldigi can be found as a free download from sourceforge.net, w1hkj.com and other sites. Ham operators also have good results with other decode programs like Ham Radio Deluxe - DM780.
Each week, Dr. Elliot updates voaradiogram.net to preview the upcoming weekend transmissions and what modes will be used. VOA Radiogram is broadcast from the Edward R. Murrow transmitting site in Greenville, N.C.
Times (UTC) and frequencies are as follows: Sat 0930-1000 5745 kHz, Sat 1600-1630 17580 kHz, Sun 0230-0300 5745 kHz, Sun 1930-2000 15670 kHz.
73 for now!
Pete Miller
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