Tag Archives: Radio World

Cambridge Consultants design a prototype $10 DRM receiver

DRM broadcast (left) as seen via a KiwiSDR spectrum display.

Many thanks to SWLing Post contributor, Michael Bird, who shares the following news via Cambridge Consultants:

Digital launched, ever so long ago, with TV and radio. So what’s the big story? It’s that the last piece of the digital jigsaw is finally in place: a system called Digital Radio Mondiale (DRM), designed to deliver FM-radio-like quality using the medium wave and short wave bands.

We’re familiar with AM on medium wave and accustomed to the horrible buzz, splat, fade away and back again. But it does have a great advantage in that it will reach for hundreds of miles from a single transmitter. That’s a lot easier than FM or DAB, which both need transmitters every 30 or 40 miles. No fewer than 443 DAB transmitter sites are needed to cover the UK alone.

So take a modern digital scheme, apply some clever (and low cost) computing power, and you can get good sound for hundreds of miles. You get to choose radio stations by name instead of kilohertz, and you can even receive text and pictures. Emergency warning and information features are also built into DRM.

Great technology. But will it fly? Is it available for everyone?

The new news is that India, through its national broadcaster All India Radio, has invested in and rolled out a national DRM service, live today. Just 35 transmitters cover that large country. New cars in India have DRM radios in them now. Other countries like South Africa, Malaysia and Brazil are likely to follow India’s lead.

But something’s missing. The radios that can receive DRM are still prohibitively expensive, especially for those markets that would benefit most. So vast swathes of the world remain unconnected to the services that DRM can provide. Where’s the cheap portable that you can pick up from a supermarket to listen to the news or sport?

Cambridge Consultants has just held its annual Innovation Day, where we throw open our doors to industry leaders and reveal future technology. One of our highlights was the prototype of a DRM design that will cost ten dollars or less to produce, addressing that vital need for information by the 60-ish per cent of our global population that doesn’t have internet or TV. It’s low power, so can run from solar or wind-up.

This design will be ready in 2020, available for any radio manufacturer to licence and incorporate into its own products. We’re doing our bit to make affordable radios for every corner of the globe!

Click here to read this post at the Cambridge Consultants website.

Michael also shares this piece from Radio World regarding this project.

I must admit: there have been so many proposed low-cost DRM receiver designs that never came to fruition, it’s easy to be skeptical. I assume the $10/9 Euro design will be for the receiver chip only–not the full portable radio, of course. They plan to bring this to fruition in 2020, so we’ll soon know if they succeed.

Hungary conducts low-power DRM tests

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Budapest, Hungary (Photo by @DNovac)

(Source: Radio World via Michael Bird)

BUDAPEST, Hungary — Digital Radio Mondiale transmissions began from Budapest, Hungary, last June. Although two Hungarian broadcasters previously tested DRM on medium wave, the transmissions are the country’s first DRM trials on shortwave.

The Department of Broadcast Info-Communications and Electronic Theory at the Budapest University of Technology is conducting these latest trials. Csaba Szombathy, head of the broadcasting laboratory, is also head of the project, which will last for at least 12 months.

While the 11-meter 26,060 kHz frequency is well known for use in local broadcasting, it’s rarely implemented for international broadcasting. […] Researchers have also performed tests in this frequency to measure coverage and determine optimal mode and bandwidth on various occasions in Mexico and Brazil. The new Hungarian trials will add to this research.

Szombathy initially operated the transmitter with just 10 W of power into a 5/8-inch vertical monopole. Radio Maria, a Catholic station, is providing a 25-hour program loop, while a Dream DRM software-based encoder broadcasts the signal using AAC encoding. In spite of the low power, the program was reportedly received in the Netherlands.

In early September, Szombathy moved the antenna and transmitter to a slightly different location to improve coverage. He increased the power to 100 W.[…]

Click here to read the full article at Radio World.

FCC to consider allowing AM broadcasters to transition to digital

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(Source: Radio World)

All-Digital on the AM Band? The FCC Might Allow It Soon

AM radio station operators in the United States may soon have the option of switching their transmissions to all-digital.

It’s not a done deal; but the concept is about to take a step closer to reality, because the Federal Communications Commission will consider a proposal at its next meeting that would start a process. It will take comments on whether to allow AM band licensees to make the switch if they want.

Ben Downs, VP/GM of Bryan Broadcasting in Texas, petitioned the FCC in March to initiate a proceeding to authorize the all-digital mode of HD Radio.

Allowing stations to use all-digital transmission is an idea that some broadcasters feel could give business-challenged AM stations in the United States new life or at least another option. Turning off their analog signals would mean that most existing receivers could no longer pick up that signal; but many AM broadcasters are currently heard on FM translator simulcasts now. And adding the all-digital AM option could open up new possibilities for them as the number of digital receivers in the marketplace continues to grow.

[…]Chairman Ajit Pai described the proposal in a blog post Monday: “Just as the FCC is trying to keep pace with changes in the market, so are AM radio operators, and the commission wants to give them as much flexibility as possible to compete in the digital age,” Pai wrote.[…]

Read the full article at Radio World.

Click here to read the proposal (PDF) that will be discussed at the November FCC meeting.

The Radio World article mentions WWFD in Frederick, MD–a station that has been broadcasting AM digital for over a year. We posted a note about this last year and I even included a short recording/video with reception when traveling through the area.

DRM: a solution to the “medium-wave problem”–?

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(Source: Radio World)

Is medium wave in decline? Some people think so.

In the 1950s radio was declared mortally wounded by TV. But then FM with its new music rescued it, becoming one of the most successful technologies and platforms ever. Radio survived and thrived but AM should have died at the hands of the nimbler, younger and more attractive FM.

Only it did not and the medium reinvented itself by using presenter-led programming, commercial music and sport. In the United States it took until the end of 1990s for the FM and AM audiences to be equal and to this day the big AM stations are going strong, bringing in the ad dollars.

REASONS

Still, it’s undeniable that the whiff of decline has enveloped AM in the past two decades. The reasons are well-known: Analog medium wave doesn’t always deliver the best sound, it can suffer from interference, it can behave annoyingly different by day and night and even by season. Medium wave mainly appeals to a maturing population (a global phenomenon, considered shameful by some!) using aging receivers (this is bad!).

[…]

THE SOLUTION

Recently cricket fans were able to enjoy an open-air demonstration of three different DRM programs on one frequency ahead of an important match in Bangalore. The fans also received data (stock exchange values) available on radio screens. This demonstrated that digital DRM is a game changer for medium wave.

In DRM the crackling audio disappears as sound is as good of that on FM. The electricity consumption and costs decrease, the spectrum is trebled and reception, even in cars (as available in over 1.5 million cars in India currently) is excellent, too.

If it is so good then why isn’t DRM medium wave conquering the world faster? Maybe it’s about confidence in a new platform. Broadcasters and governments need to market DRM digital radio once signals are on air in their countries.

As for receiver availability and their costs, let us remember how many receivers were on sale in the 1970s when FM was taking over the world. Nowadays, many listeners consume radio in their cars rather than sit in front of a retro looking wooden box. Digital receivers (DRM alone or DRM/DAB+) are a reality and a bigger push for digital would help with volumes sold thus bringing down the prices.[…]

Click here to read the full article at Radio World.

Radio World: “Historic Woofferton Boasts a Modern Twist”

“North Korea Resumes DRM Broadcasts”

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(Source: Radio World via Michael Bird)

North Korea has returned to digital radio broadcasting after an absence of nearly two years.

The latest Digital Radio Mondiale (DRM) shortwave transmissions began mid August. The country has had periodic DRM broadcasts for many years.

It appears unclear at this time however whether the current series of transmissions will soon end or be the start of a regular service.

Thus far, all of the latest test transmissions have taken place on 3560 kHz, which is actually allocated for amateur radio use.

According to radio enthusiasts in the region, the signal has been clear and very audible.[…]

Click here to read the full article at Radio World.

History of the Armed Forces Radio Service

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Humphrey Bogart and Lauren Bacall being interviewed by the Armed Forces Radio Service (Source: Wikipedia)

Many thanks to SWLing Post contributor, Ron, who shares this article from Radio World:

We can’t fully appreciate the importance of news from home to those who served in World War II. In the Pacific campaigns, G.I.s, sailors and Marines fought bloody island-hopping battles; as each island was cleared, garrison troops and hospitals moved in and carried on their own war against mosquitoes, isolation and boredom. The island fighters were fortunate if dated mail caught up with them before they moved on to the next target. Timely personal-level communications were pretty much absent.

Radio programming from America was available but only on shortwave. And shortwave radios were not generally available. The fortunate few had been issued “Buddy Kits” that included a radio, a small PA system and a record player for discs sent by mail. But for most there was no way to receive short-lived information such as news and sports. They were left with enemy radio propaganda such as Japan’s “Orphan Ann/Annie” (aka one of several Tokyo Roses) and the “Zero Hour” program.

No wonder that the idea of having a local island radio station doing “live from home” was so fiercely supported. Enlightened commanders saw the idea as a terrific morale-builder. The only problem was how to pull it off.

A solution, not uniquely, came from within the ranks. It started with the work of some bored but talented soldiers in the Panama Canal Zone who in 1940 built a couple of 50 W transmitters and put them on the air without authorization, labeling them “PCAN” and “PCAC.”

In Alaska, 7,500 miles northwest of Panama City, what started as programming through a loudspeaker system became a bootleg radio operation at Kodiak. Coming on the air in January 1942 and calling itself “KODK,” it delivered a whopping 15 watts to the troops. Sources with hindsight later said that the Armed Forces Radio Service (“AFRS”) was born here, when one of its progenitors visited the Alaska operations and “came up with the idea.”[…]

Click here to continue reading the full article at Radio World.