Radio World: “China Makes Its DRM Move”

Screen Shot from a China National Radio DRM test (Source: DRM.org)

(Source: Radio World via Michael Bird)

The nation becomes world’s leading Digital Radio Mondiale shortwave broadcaster in just one year

Hans Johnson

BEIJING — It appears as if China has jumped into Digital Radio Mondiale shortwave broadcasting with both feet. Some DRM infrastructure has been in place for over a decade, but up until recently had only been sporadically tested.

Just over a year ago, China had no regular DRM presence. Today, it is the world’s largest DRM shortwave broadcaster. China operates the most DRM transmitters in this band and has the most extensive schedule.

The initial broadcasts started in early 2018 from Beijing. Services continued to rollout over the year via various transmitter sites, often on the country’s periphery.

A DRM shortwave transmitter in Beijing targets north China almost 24 hours a day. A second Beijing transmitter targets east China for eight hours a day.

Another transmitter in Ürümqi in the country’s west targets central and east China for 14 hours a day, while a transmitter in Qiqihar, Heilongjiang province (the Manchurian plain), is on more than 11 hours a day and reaches south and southwest China. Dongfang on Hainan Island province is on eight hours a day on two frequencies for both north and southeast China. Finally, the DRM shortwave transmitter located in Kunming in the Yunnan province is on eight hours daily for south China. There is now a DRM network providing nationwide coverage.

By comparison All India Radio has 11.5 hours a day of shortwave time coming from a single transmitter. The Indian broadcaster has as many as three more DRM-capable shortwave transmitters but they are not on air at present. India does operate 38 AM (medium wave) transmitters for its domestic network, however.[…]

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

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Book Review: “Radio Reader: Essays in the Cultural History of Radio”

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Many thanks to SWLing Post contributor, Dave Kolesar, who shares the following review:

Just finished another excellent read: Hilmes and Loviglio’s collection “Radio Reader: Essays in the Cultural History of Radio.”

Very little scholarship exists about the cultural impact of radio in America, and this volume explores the history highlights (long partial list): the initial fight over the nature of broadcasting in the 1920s and 30s (educational vs. commercial), stratification of programming and channels with regards to representation of women, people of color, and gays during the Depression, WWII, and the pre-televison era, the discovery of the teenage market in the 1950s that led to the Top 40 format, the commerical Underground radio movement of the 60s, the creation of NPR and the associated decimation of student-run university stations, the rise of commercial (in everything but name) religious broadcasting and and its corrupting effects on the religious experience and political discourse, the 1980s male-dominated talk radio genre as an effort to roll back feminism, the 1996 Telecom bill and the creation of LPFM and the proliferation of pirate radio as responses to it, and finally, the digital radio future and its public service obligations.

For those who love the medium, this is a great reminder of why we work in it, how it’s succeeded and yet failed to live up to its potential, and what the future may hold as new technologies enter the audio landscape.

Thanks, Dave—sounds like this collection spans a wide variety of radio cultural histories. I did some searching and found that, of course it’s on Amazon.com, but also available used on a number of sites including Barnes and Noble.

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Shortwave Radio Recordings: Voice of Peace from Baghdad – December 29, 1990

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Gary regrets getting his refurbished Sangean PR-D4W

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You might recall this previous post regarding a limited number of refurbished Sangean PR-D4W units on Amazon.com. Gary notes that he regrets making this purchase:

“Sadly, my refurbished PR-D4W only worked well for a little over one day. Now, medium strength and weaker AM stations have a greatly reduced audio level. Before, they sounded fine. It seems like the AGC is faulty.”

Read his full reply on the Herculodge blog.

And sadly this is the issue with refurbished products.

I spoke with a radio manufacturer once about their process of refurbishing radios. They have a very specific check list, testing and burn-in period after addressing the reported issue. More often than not, refurbished radios come from an inventory of “open box” units where the customer took delivery, opened the box, but returned the unit without reason during the warranty period. Some radios, however, have reported issues and the technician addresses the issue, tests the radio, cleans it, then repackages it. On occasion, some issues slip through because the problem doesn’t show up during the burn in period.

This likely could be the case with your unit, Gary, and you did the right thing to solve it: return it to the retailer!

Thank you for sharing the follow-up!

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2019 Orlando Hamcation Flea Market Photos

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Many thanks to SWLing Post contributor, Rich Nowak, who kindly shares photos from the Orlando Hamcation Flea Market.

Click on each image to enlarge:

What an impressive amount of vintage radios! I’m planning to attend Hamcation next year (2020)–now I know I’ll need to bring my truck to haul back all of the boat anchors! 🙂

Thank you for sharing these, Rich!

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Top 10 DX Of The Year Contest Results!

US Navy finds ham radio training makes “workers better at their jobs”

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(Source: Southgate ARC via Mike K8RAT)

Can learning amateur radio make for better engineers and software developers?

Writing in C4ISRNET – Electronic Warfare, Eric Tegler says:

When a group of [US] Navy engineers and software developers took time away from their day jobs in December, they spent the time pursuing a task long considered passe: they became licensed amateur radio operators.

Some 23 employees from Naval Air Warfare Center Weapons Division (NAWCWD) took a week-long class in amateur radio at Point Mugu, California culminating with an FCC amateur radio license test. All passed and are certified at the “technician” level for amateur radio operation [permitted 200 watts on some HF bands, 1500 watts above 30 MHz].

Now, Navy officials say the move may make the workers better at their jobs. The staff gained an understanding of radio frequency (RF) propagation that’s essential to what they do, said Brian Hill, electromagnetic maneuver warfare experimentation lead and collaborative electronic warfare supervisor at NAWCWD.

Hill, who earned his amateur radio license in high school, noticed that while most of his department’s recent hires had degrees in computer science, many had little background in RF theory or operation.

“You can explain antenna patterns and concepts like omni-directional vs directional using Smith charts, but it’s helpful to add a demonstration to really convey the concept,” Hill said. “You can explain modulation as a concept, but for a demo… let them listen to how modulated digital signals with audio frequencies sound… For those who never knew the joy of hearing a 2400 bps modem connect over a telephone line, it was a new concept!”

These concepts are central to electromagnetic maneuver warfare.

“We need to be able to have awareness of all threats and opportunities from [zero frequency] to light within an integrated system,” Hill said. “Our adversaries are looking at the entire spectrum to use against us, and we need to do the same. Having awareness of how the atmosphere changes from daylight to night and how that affects propagation of [high frequency] is important.”

This can be critical for young developers/engineers whose experience is typically limited to the UHF/EHF-based systems now in vogue across communications, guidance and ISR technologies.

Read the full story at
https://www.c4isrnet.com/electronic-warfare/2019/02/06/can-learning-ham-radio-make-for-better-engineers-and-software-developers/