Category Archives: Digital Modes

WRMI to showcase digital modes via analog radio

31-meter-Spectrum (Source: VOA Radiogram via Richard Langley)

WRMI, Radio Miami International, will showcase digital text and images via analog radio in a half-hour special broadcast to be transmitted nine times (at least), beginning Saturday, 13 August.

The broadcast will mostly be in MFSK32 centered on 1500 Hz. There will also be segments in MFSK64, MFSK32 centered on 2200 Hz, and Olivia 64-2000. The program will include MFSK images, examples of non-Latin alphabets, and an Flmsg transmission. You will also hear “co-channel” music.

To decode the modes on the WRMI broadcast, Fldigi software is recommended. Download it fromhttps://sourceforge.net/projects/fldigi/files/fldigi/ . The main Fldigi website is http://www.w1hkj.com.

And you will use the companion program Flmsg. Download it fromhttps://sourceforge.net/projects/fldigi/files/flmsg/ .

To make Flmsg work with Fldigi, in Fldigi: Configure > Misc > NBEMS > under Reception of flmsg files, select Open with flmsg and Open in browser, and below that indicate where your Flmsg.exe file is located – probably somewhere in Program Files(x86).

For correct decoding of the languages with diacritics, or using non-Latin alphabets, in Fldigi: Configure > Colors & Fonts > RxTx > in the Rx/Tx Character set menu, select UTF-8.

For Fldigi to automatically select the mode and the center audio frequency of the mode, select RxID (upper right of the interface) by left clicking. In newer versions of Fldigi, also right click on RxID and select Passband.

You can decode this WRMI special broadcast as it is broadcast, or from your recording.

TRANSMISSION SCHEDULE

Via WRMI’s transmitters at Okeechobee, Florida, except where noted:

Saturday 13 August 0030-0100 UTC on 7730 kHz (285 degrees azimuth)
Saturday 13 August 0730-0800 UTC on 5850 kHz (315 degrees)
Saturday 13 August 1330-1400 UTC on 11580 kHz (44 degrees)
Saturday 13 August 2200-2230 UTC on 5950 kHz (181 degrees)
Sunday 14 August 0230-0300 UTC on 11580 kHz (44 degrees)
Sunday 14 August 2130-2200 UTC on 15770 kHz (44 degrees)*
Sunday 14 August 2330-2330 UTC on 11580 kHz (44 degrees)*
Monday 15 August 2000-2030 UTC on 6070 kHz* **
Tuesday 16 August 2130-2200 UTC on 15770 kHz (44 degrees)

* Preempts DigiDX, usually heard at this time

** Via Channel 292, Germany

Many of these broadcasts will be heard outside their nominal target areas.

Reception reports to Jeff: info (at) wrmi.net

There’s a pattern in that noise!

Digital-Image-VOA-Radiogram

Many thanks to SWLing Post contributor, @K7al_L3afta, who just shared the image (above) and noted, on Twitter:

“I just discovered the noise at the start of [the VOA Radiogram has] a purpose!” 

That’s a brilliant discovery!

Click here to learn about the VOA Radiogram.

Click here to follow @K7al_L3afta on Twitter.

TDF Group to use DRM 30 as shortwave communications system

Click to enlarge. Source: TDF Group

Click to enlarge. Source: TDF Group

(Source: Radio Mag Online)

PARIS — The use of the medium and short wave bands can provide extensive coverage at low cost in inaccessible locations or for those at a disadvantage due to lack of infrastructure.

[…]France’s TDF Group has started a project they call SmartCast that aims to study and build a long range broadcast system, with potential interactivity where appropriate — by way of a low-speed wireless return path. Data including audio will be broadcast in a shared stream based on standard DRM 30 from Digital Radio Mondiale.

Work underway by TDF includes development of services and equipment focused on two markets:

  • Maritime Navigation, with a set of services designated as “NavCAST”.
  • International Broadcasting, with a set of services designated as “WideCAST.”[…]

Read the full article at RadioMagOnline.com

BBG, take note: Shortwave radio distributes smartphone apps

smart-phones

Many thanks to Andy Sennitt, who posted a link to this Mission Networks News article on Facebook.

Imagine being able to download an app…without the internet.

Well, it’s finally happened, thanks to shortwave radio.  Broadcasting Board of Governors (BBG), take note:  Faith Comes By Hearing (FCBH), a Christian organization that distributes Bibles in parts of the world where they are difficult to distribute, have a free smartphone app called Bible.is.  The only problem is, the app wasn’t available in countries where there is no access to the Internet nor where authorities block the app…at least, until now. By using Trans World Radio’s Guam shortwave transmitter site, they have successfully “downloaded” this app to multiple smartphones in Thailand:

[D]ue to a major recent breakthrough by Faith Comes By Hearing (FCBH), they were able to deliver the Bible to an unconnected smartphone using shortwave radio towers over 3,000 miles for the first time ever.

Troy Carl, Vice President of FCBH, explains, “Yesterday, we were able to transmit file casting data packets from Guam all the way to Thailand using shortwave frequencies, and we were able to do that in partnership with Trans World Radio. So it was really quite exciting! Basically what we did is created one-way internet access turning that tower into a super WiFi router. And that’s quite a story because it’s never been done!”

To put it another way, Carl wrote this description in a recent post:

Just like the one you use everyday in your house, where you connect a data source (internet cable) and a power source (you plug it in) and the little antennas broadcast internet around your house (say 500 ft.) and you connect to it with your phone to read/listen/see the data it’s transmitting.

In Guam, we took a HUGE antenna, (supplied by Trans World Radio), hooked up a data source (a Bible.is app device), turned the power on (250kw) and sent the data into the air bouncing it off the ionosphere over 3,000 MILES!

Our team in Chang Mai Thailand, hooked up to this giant router with a proprietary decompiler. Then sideloaded the Bible.is app with all its content to multiple smart phones using a simple wifi broadcaster!

As I wrote in, Does Shortwave Radio Have a Future?, I’ve always believed that the shortwave medium could be leveraged for international digital/data communications, and should be, especially in countries under repressive regimes such as North Korea. In my article, I focused on Radio Canada International (RCI), which was then dismantling their shortwave transmitter site:

[B]roadcasters should not dismantle their transmission sites as Canada is currently doing. Not only is the current service originating from these sites a more reliable form of emergency communications than the Internet, should a national disaster befall us; not only do they continue to provide a broad-spectrum mode of diplomacy; but should future digital communication modes find a way to take advantage of the HF spectrum as is now under discussion, this would be most unfortunate.

Imagine a wi-fi signal with a footprint as large as several countries, digital devices with tiny fractal antennas that receive this signal containing rich media (e.g., audio and video)––these are not science fiction, but highly plausible uses of these transmission sites, even within the next decade…

FCBH’s innovation is simply a first step in this direction. If it turns out that this method is both accessible and affordable, this could truly pave a new road on the mobile information highway.

Walt’s decoded image from “The Classics Experience”

Many thanks to SWLing Post reader, Walter Salmaniw, who comments:

ClasssicsExperienceI reviewed Paul’s excellent program this morning and worked on decoding the image broadcast during his 2nd hour.

Unfortunately the slant was all wrong! But gradually, working the slant on the Fldigi resulted in a nice image of his dog [see image on right], using about -6250 (Configure > Soundcard > Settings >RX Corrections.

Thanks for a great program, Paul!

Thanks for sharing the image, Walter!

Paul, I think it’s brilliant that you included your beagle in the show! Thanks for putting the great tunes and content on the air!