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Hey Don’t Forget About Radiogram

VOA Radiogram is a VOA program experimenting with digital text and images via shortwave broadcasting

Paul McLane is editor of Radio World.

Hey, don’t forget about Radiogram!

That’s what Bennett Kobb and Christopher Rumbaugh are telling the Broadcasting Board of Governors.

BBG, as longtime readers know, oversees U.S. international broadcasting organizations like Voice of America and Radio Free Asia. The board in recent years has been following a path trod by other large shortwave broadcasters, scaling back use of traditional shortwave infrastructure in favor of online, FM, TV and other media channels.

The organization has emphasized that it remains committed to using shortwave where it is needed. Nevertheless, many facilities have closed over the years, and BBG recently established a committee to research the future of shortwave as it relates to U.S. public policy and national security. It sought public comments.

Among those replying were Kobb and Rumbaugh. One works for a trade association, the other is a library manager and web publisher; but they were writing as individuals.

They want to draw attention to VOA Radiogram, a form of international high-frequency broadcasting. Radiogram is a VOA program experimenting with digital text and images via shortwave broadcasting; it’s produced and presented by Dr. Kim Andrew Elliott.

“Radiogram is soundly premised on modern digital techniques and mitigates longstanding impediments to HF transmission,” Kobb and Rumbaugh wrote in their comments to BBG. “Users around the world have documented reception of 50 VOA Radiogram programs in more than a thousand YouTube videos. BBG must not allow its own pioneering developments to wither, but should advance them toward operational status.”

Kobb noted this image of a car, posted on the Radiogram site and illustrating good quality obtained by listeners in several countries. The captions state the location received and time of the VOA broadcast.
Radiogram broadcasts Web content via error-detecting/correcting AM tone modulation, using standardized formats commonly used by ham radio. They say this approach is robust and resistant to interference.

“The user’s ordinary shortwave receiver, tuned to a Radiogram transmission, feeds its audio to a user device. These could include mobile phones, tablets, laptop and desktop computers and the new ARM-based miniature computers and embedded devices. The user device decodes the tones and displays text and imagery despite propagation impairments and intentional interference — and without Internet connection.”

They point out that no hardwire connection is required; putting the radio near the phone or computer is usually sufficient. “By adding a simple audio cable between receiver and user device, however, reception can be silent and covert. No specialized hardware is needed, and the software platform for decoding is long in the public domain.”

A news story received with VOA logo.
They have further ideas. Another approach would use “dongle” technology that puts a software-defined radio inside a USB enclosure. “The operating system and decoding software could also be incorporated into the device, which could boot the computer, eliminating the need to install any PC software.”

The user need not be present to receive content, and essentially receives a web magazine “updated at will and always ready for use” that can be redistributed.

“Naturally, the audio tone transmission can be recorded for later playback. Even when buried well under music or noise, the nearly inaudible recorded broadcast can nevertheless deliver 100% copy upon decode. “

Radiogram’s transmission methods provide text at 120 words per minute, along with images.

“Sent over regular broadcast transmitters (no modifications needed), this approach effectively extends the reach of the transmitter. In other words, the digital text mode will decode in locations where the audible speech over the same transmitter would be too low for aural intelligibility. The audio recorded or captured could be replayed over another transmitter to even further extend the reach of the broadcast.”

They conclude that BBG should capitalize on Radiogram as a “circumvention tool, readily consumable by mobile devices,” and integrate Radiogram into its media strategy and networks. They want the board to reconfigure HF facilities with Radiogram in mind, and support development and distribution of open-source Radiogram decoding applications for mobile devices and platforms.

The window to comment to BBG about shortwave has closed, but we welcome ongoing discussion. Post below or send letters to the editor to [email protected].