DRM30 on a Smartphone: KTWR Shows Us The Way

Image via the KTWR Blog

Many thanks to SWLing Post contributor, Dan Van Hoy, who writes:

[Regarding the reception of DRM via smart phone,] I happened to find this KTWR Guam post about decoding DRM30 with a smart phone, app, and an RTL-SDR:

Convert Smart Phone to DRM 30 HF receiver!

We are pleased to report successful use of an SDR Dongle used to directly receive and Decode DRM 30 over HF today.

The SDR Dongle is an RTLSDR v3 type connected to an android smartphone using an OTG cable (phone or tablet must be OTG capable).

The Software used:
1. Android driver (free)
2. DRM+SDR Android App ($4.99)

The Frequency of the HF broadcast is directly assigned within the DRM+ SDR app with two settings
1. Frequency in Hertz
2. RF Gain (0-512)

Demonstration video showing Clean DRM decode of AAC Audio and Journaline data along with live metadata.  (our signal was very strong, so only a short wire used for Antenna, DX’rs will need an appropriate Antenna)

Now anyone with a smartphone and a $20 SDR can receive DRM 30 HF broadcasts…

Click here to read this post on the KTWR blog.

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2020 Radio Prague QSL Cards

Many thanks to SWLing Post contributor, David Iurescia (LW4DAF), who writes:

“These are the new 2020 QSL Cards from Radio Prague International.
The theme of this year is “Transmitters” (Antennas):”

(Source: Radio Prague)

The three letters – QSL – constitute one of the codes originally developed in the days of the telegraph. All codes consisted of three letters beginning with “Q”. Later some of these “Q” codes were adopted by radio-telegraphists and radio listeners. QSL means “contact confirmed” or “reception confirmed”.

The expression “QSL card” or just “QSL” gradually came to be used among radio-amateurs and then more broadly as radio began to develop as a mass medium. Radio stations were keen to know how well and how far away their programmes could be heard and began to send their listeners “QSL cards” in return for reception reports. The card would include letters making up the “call sign” of the station – the system still used in the United States – or the broadcasting company’s logo or some other illustration. The card would also include a text stating the frequency and the transmitter output power, and a confirmation of when the listener heard the station.

Domestic broadcasters do not tend to use QSL cards these days, but their popularity remains among radio stations broadcasting internationally. They are still keen to know how well they can be heard in the parts of the world to which they broadcast. In the era of shortwave broadcasts Radio Prague sent out QSL cards for reception reports received. After curtailing our shortwave transmissions as of February 1, 2011 we will continue issuing QSL cards for reception via the Internet.

Here you can look through our current and past series of QSL cards:

Click here to view all of the new QSL cards from Radio Prague.

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External FM antenna for Android phones/tablets

Many thanks to SWLing Post contributor, Adid, who writes:

Check this little gadget for android phones or tablets

https://www.aliexpress.com/item/32976847250.html

If they have the FM app installed than this will come handy.

One needs to select speaker and not earphone as expected.

It works fine here. (I don’t know if Apple phones have an FM module)

Thank you, Adid! Very cool! This little antenna costs $0.90 USD–an insanely low price.

If you have an old set of earphones lying around the house (I probably have two dozen that ship with various radios) you could also snip off the earpieces and use the pigtail as a wire FM antenna.

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Ham CAP and VOA Prop: Fixing SSN look-up files

VOA Prop

Many thanks to SWLing Post contributor, Paul Evans, who notes:

Users of these two propagation prediction programs will find that they don’t work beyond Dec 2019 because the SSN look-up files didn’t go any further.

I noticed this 2-3 years ago and added to the end of the files required. I entered guesses for solar activity values, but with auto mode turned on they will fetch current values. At least this will get you started again. Or my guesses might be right!! 🙂

For Ham CAP use: http://w4.vp9kf.com/SSN.dat

For VOAProp use: http://w4.vp9kf.com/ssndata.txt

Download them and swap them into the directory where the application is located.

Thanks or the help, Paul!

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An app to decode DRM?

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

Many thanks to SWLing Post contributor, Richard Langley, who shares this story by Hans Johnson at Radio World:

Can an App Solve the DRM Receiver Problem? (Radio World)

The Digital Radio Mondiale standard for digital broadcasting in long, medium, and shortwave bands offers the possibility to transmit audio, text and pictures.

A few broadcasters use DRM for both domestic and international transmissions. DRM’s largest problem is lack of receivers, especially affordable standalone ones.

Some listeners use an SDR, computer and free Dream software to receive the DRM signals, but this audience doesn’t make up the mass audience that broadcasters are looking for.

[…]AlgorKorea didn’t develop the apps with the intention of solving the DRM receiver issue. They developed them to resolve a problem with FM hearing aids used in classrooms.

So how do they work? The DRM+SDR version couples the popular and inexpensive RTL-SDR to an Android device with a USB OTG adapter.[…]

Click here to read the full article at Radio World.

 

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Shortwave version of the Southgate ARC News

Many thanks to SWLing Post contributor, Harald (DL1AX), who shares the following message from the Southgate ARC:

Southgate News is now on ShortWaveRadio

We now have a regular Sunday morning news broadcast on ShortWaveRadio.de
So tune in every Sunday at 10am UTC on 3975 and 6160 kHz.
The programme is repeated at 14:00 UTC on 6160 kHz and 16:00 UTC on 3975 kHz

Thanks Harald! Southgate is a wonderful source of radio news. I look forward to checking out their shortwave broadcast!

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Encore – Classical Music – New Broadcast time Europe – Saturday 11:00 UTC

This weekend Encore – Classical Music on Radio Tumbril will be broadcast again at the NEW TIME in Europe of 11:00 UTC on SATURDAY on 6070 kHz.
This is instead of the Sunday broadcast at 15:00 UTC.
There is much less interference from adjacent channels at this time – indeed we have had several reception reports from India.
For now – the 6070 kHz repeat will continue to be on Friday evenings at 19:00 UTC – as usual.
WWCR Nashville will broadcast the Encore on Saturday at 21:00 UTC as usual on 9350 kHz. The propagation is very good over the US and much of Canada and the signal carries to parts of western Europe too.
WBCQ Maine will send out the show on 7490 kHz at 01:00 UTC Monday to the US. (Early evening Sunday local US – obviously.)
NB – trial broadcast of Encore on 7440 kHz Sunday 09:00 UTC Channel 292 – Sunday 19th
Do let us know how well you can pick up Encore at your location by emailing to [email protected]. We try to reply to all emails and will send eQSL cards for full reports – though a brief report is fine.
This week’s programme is chock full of interesting and provocative classical music – listen in and see if you agree.
The playlist is on the website and will be updated soon after Saturday’s broadcast of the new show by Channel 292 at 11:00 UTC.
Both Channel 292 and WBCQ as well as WWCR can be pulled live off the internet if the reception is poor in your location. Easy to find their sites with a google search.
In the meantime – thank you for spreading the word about Encore – Classical Music on Shortwave. And thank you to everyone for letting us know how well the signal is received where you live.
Brice Avery – Encore – Radio Tumbril.
Regular Broadcast times are:
11:00 – 12:00 UTC Saturday on 6070 kHz and repeated 19:00 – 20:00 UTC Friday on 6070 kHz Channel 292 (Germany).
21:00 – 22:00 UTC Saturday on 9350 kHz WWCR (Nashville).
01:00 – 02:00 UTC Monday on 7490 kHz WBCQ – (Maine).
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