Tag Archives: IEEE Spectrum

IEEE Spectrum: Build a Long-Distance Data Network Using Ham Radio

(Source: F4HKD via YouTube)

(Source: IEEE Spectrum)

Send data via IPv4 up to 300 kilometers with easy-to-assemble hardware

By F4HDK

I have been a hobbyist and maker for almost 15 years now. I like inventing things and diving into low-level things. In 2013, I was looking at a protocol called NBP, used to create a data network over amateur radio links. NBP was developed in the 2000s as a potential replacement for the venerable AX.25 protocol [PDF] that’s been in use for digital links since the mid-1980s. I believed it was possible to create an even better protocol with a modern design that would be easier to use and inexpensive to physically implement.

It took six years, but the result is New Packet Radio (NPR), which I chose to publish under my call sign, F4HDK, as a nom de plume. It supports today’s de facto universal standard of communication—the Internet’s IPv4—and allows data to be transmitted at up to 500 kilobits per second on the popular 70-centimeter UHF ham radio band. Admittedly, 500 kb/s is not as fast as the megabits per second that flow through amateur networks such as the European Hamnet or U.S. AREDN, which use gigahertz frequencies like those of Wi-Fi. But it is still faster than the 1.2 kb/s normally used by AX.25 links, and the 70-cm band permits long-distance links even when obstructions prevent line-of-sight transmissions.

Initially, I considered using different frequency bands for the uplink and downlink connections: Downlinks would have used the DVB-S standard, originally developed for digital satellite television. Uplinks would have used a variation of FSK (frequency-shift keying) to encode data. But the complexity involved in synchronizing the uplink and downlink was too high. Then I tried using a software-defined radio equipped with a field-programmable gate array (FPGA). I had some experience with FPGAs thanks to a previous project in which I had implemented a complete custom CPU using an Altera Cyclone 4 FPGA. The goal was to do all the modulation and demodulation using the FPGA, but again the method was too complex. I lost almost two years chasing these ideas to their dead ends.

Then, in one of those why-didn’t-I-think-of-this-earlier moments, I turned to ISM (industrial, scientific, and medical) chips.[…]

Click here to read the full article.

Many thanks to SWLing Post contributor, Marty, for the tip!

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A liquid-based VHF/UHF steerable antenna

Many thanks to SWLing Post contributor, Marty, who shares this fascinating article from the IEEE Spectrum:

A new antenna that uses saltwater and plastic instead of metal to shape radio signals could make it easier to build networks that use VHF and UHF signals.

Being able to focus the energy of a radio signal towards a given receiver means you can increase the range and efficiency of transmissions. If you know the location of the receiver, and are sure that it’s going to stay put, you can simply use an antenna that is shaped to emit energy mostly in one direction and point it. But if the receiver’s location is uncertain, or if it’s moving, or if you’d like to switch to a different receiver, then things get tricky. In this case, engineers often fall back on a technique called beam-steering or beamforming, and doing it at at a large scale is one of the key underlying mechanisms behind the rollout of 5G networks.

Beam-steering lets you adjust the focus of antenna without having to move it around to point in different directions. It involves adjusting the relative phases of a set of radio waves at the antenna: these waves interfere constructively and destructively, cancelling out in unwanted directions and reinforcing the signal in the direction you want to send it. Different beam patterns, or states, are also possible—for example, you might want a broader beam if you are sending the same signal to multiple receivers in a given direction, or a tighter beam if you are talking to just one.[…]

Click here to read the full article.

 

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IEEE Spectrum: “Is Ham Radio a Hobby, a Utility…or Both?”

Many thanks to a number of SWLing Post readers who have shared a link to the following article that follows the debate and discussion over an FCC proposal–RM-11831 (PDF)–to “Reduce Interference and Add Transparency to Digital Data Communications.”

The IEEE article, written by Julianne Pepitone, covers both sides of the debate:

Is Ham Radio a Hobby, a Utility…or Both? A Battle Over Spectrum Heats Up

Some think automated radio emails are mucking up the spectrum reserved for amateur radio, while others say these new offerings provide a useful service

Like many amateur radio fans his age, Ron Kolarik, 71, still recalls the “pure magic” of his first ham experience nearly 60 years ago. Lately, though, encrypted messages have begun to infiltrate the amateur bands in ways that he says are antithetical to the spirit of this beloved hobby.

So Kolarik filed a petition, RM-11831 [PDF], to the U.S. Federal Communications Commission (FCC) proposing a rule change to “Reduce Interference and Add Transparency to Digital Data Communications.” And as the proposal makes its way through the FCC’s process, it has stirred up heated debate that goes straight to the heart of what ham radio is, and ought to be.

The core questions: Should amateur radio—and its precious spectrum—be protected purely as a hobby, or is it a utility that delivers data traffic? Or is it both? And who gets to decide?

Since Kolarik filed his petition in late 2018, this debate has engulfed the ham world. Fierce defenders of both sides have filed passionate letters and comments to the FCC arguing their cases.

On one side is Kolarik in Nebraska. In his view, it’s all rather simple: “Transparency is a core part of ham radio,” he says. “And yet, you can find tons of traffic from automatic[ally controlled digital] stations that are extremely difficult to identify, if you can identify them at all, and they cause interference.”

The automatically controlled digital stations (ACDS) Kolarik refers to can serve to power services like Winlink, a “global radio email” system.

Overseen and operated by licensed volunteers around the globe, Winlink is funded and guided by the Amateur Radio Safety Foundation, Inc. (ARSFI). The service uses amateur and government radio frequencies around the globe to send email messages by radio. Users initiate the transmission through an Internet connection, or go Internet-free and use smart-network radio relays.

On Winlink’s website, the service says it provides its licensed users the ability to send email with attachments, plus messages about their positions, and weather and information bulletins. Representatives of the service say it also allows users to participate in emergency and disaster relief communications.

But Kolarik’s petition argues two points: First, because such messages “are not readily and freely able to be decoded,” the FCC should require all digital codes to use protocols that “can be monitored in entirety by third parties with freely available, open-source software.” Secondly, he wants the rule change to reduce the interference that he says services like Winlink can create between amateur-to-amateur stations—by relegating the often-unattended automatic stations to operate solely on narrower sub-bands.

Loring Kutchins, the president of ARSFI, says he believes Kolarik’s petition is “well intentioned in its basis. But the fundamental conflict is between people who believe amateur radio is about hobby, not about utility. But nowhere do the FCC rules use the word ‘hobby.’”[…]

Click here to continue reading the full article on the IEEE Spectrum website.

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CES Hall of Fame: The Grundig Satellit 650

Photo: Universal Radio

(Source: IEEE Spectrum via Paul)

The Consumer Electronics Hall of Fame: Grundig Satellit 650 Radio

The market for expensive shortwave radios collapsed in the early 2000s. But before it did, Grundig created a blaze of glory

Though they’ll likely deny it, long-distance (DX) radio enthusiasts are also often romantics. For DXers, as they’re known, there’s a powerful enchantment surrounding the chance reception of a signal from somewhere remote and mysterious, like the Australian Outback, the Namib Desert, or a lonely island in the Shetlands. So when they come to favor a piece of equipment, they don’t just like it, they become devotees. And one receiver seems to have earned their undying affection more than any other: the Grundig Satellit 650.[…]

Click here to read the full article at the IEEE Spectrum.

I agree: the Sat 650 is a legend! I’ve never owned one–have you?  Please comment!

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IEEE Spectrum Magazine: “This Artist Made a Radio Out of a Kitchen Sink”

(Source: IEEE Spectrum via Ed C)

Amanda Dawn Christie’s work commemorates the fading glory of shortwave radio

By Stephen Cass

Some artists work in oils, say, or marble. Amanda Dawn Christie works in radio. Not radio in the sense of performing on air. But radio in the sense of the giant cultural and technological phenomenon that is broadcasting, and specifically shortwave broadcasting.

For decades, shortwave was the only way to reach a global audience in real time. Broadcasters such as the BBC World Service and Voice of America used it to project “soft power.” But as the Internet grew, interest in shortwave diminished.

Christie’s art draws from shortwave’s history, representing it in sculpture, performance, photography, and film. Her focus is the life of the Radio Canada International (RCI) transmitter complex, located in Sackville, New Brunswick, near Christie’s hometown. The transmitter was in operation from the 1940s until 2012. “Those towers were always just a part of the landscape that I grew up around,” says Christie. It took a radio-building workshop to spark her interest: “I built a radio out of a toilet-paper tube…. I thought I did a great job because I picked up Italian radio. It turned out I did not—I was just really close to this international shortwave site.”[…]

Continue reading the full article at the IEEE Spectrum Magazine.

So great to see SWLing Post friend, Amanda Dawn Christie, featured in the IEEE Spectrum! Thanks for the tip, Ed!

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IEEE Spectrum: “Long-Running U.S. Federal Radio Stations, Beloved by Hams, in Danger of Shutdown”

A WWV Time Code Generator

(Source: IEEE Spectrum Magazine)

Several public radio stations that have broadcast the time of day continuously for nearly 100 years are on the chopping block

By Julianne Pepitone

Starting in May 1920, the U.S. federal WWV radio stations have broadcast the official time without fail. For ham radio fans, hearing the friendly “National Institute of Standards and Technology Time!” announcement is a comforting old refrain. For others, it’s a service they’ve never heard of—yet in the background, it’s what keeps the clocks and appliances in their daily lives automatically ticking along on time.

But after 98 years, this constant companion could soon go off the air. The proposed 2019 U.S. presidential budget calls for a 34 percent cut in NIST funding; in response, the Institute compiled a budget-use plan that would eliminate the WWV stations.

At first blush it might sound like the natural end to a quaint public service from a bygone era. Do we really need radio-broadcast time signals in an era of Internet-connected devices and GPS?

Many would argue: Yes, we really do. More than 50 million devices in the United States—including wall clocks, wristwatches, and industrial appliances—keep time through the signal from NIST’s WWVB station, operating from a site near Fort Collins, Colo., where it reads the time directly from an atomic clock. These radio-equipped clocks are permanently tuned to WWVB’s low-frequency 60 kHz signal.

“WWVB is the pacemaker for the world around us, even if we don’t realize it,” says Thomas Witherspoon, editor of shortwave radio news site The SWLing Post. “It’s why factory workers and schools don’t need to drag out the stepladder every time we switch between Daylight and Standard Time. Without WWVB, these devices won’t magically update themselves.”[…]

Click here to read the full article including comments from WWVB’s Station Manager.

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