This blog is dedicated to shortwave radio listening in the 21st century: the art of tuning into the signals of radio stations that are transmitting from thousands of kilometres away without the use of the Internet. It can be viewed as a fun hobby but also as a way to maintain an alternative, independent means of obtaining information in our digital age. Posts cover topics including shortwave radio equipment and accessories, station profiles, program recordings and shortwave radio history.
On August 6th, 2018, while recording the 22 and the 19 meter bands outdoors using my ultra-portable spectrum capture set-up, I decided to dust off my trusty Tecsun PL-680, hook it up to a simple long wire external antenna and use this rather sensitive radio to venture out to the opposite end of the shortwave spectrum: the 49 meter band. After tuning around for a few minutes I came across Radio Fana on 6110 kHz, which is one of Ethiopia's national stations broadcasting in the Oromo language. Below is my recording of it, starting at 1800 UTC, which I have also shared on the Shortwave Archive.
Radio Fana's transmitter is located in Addis Ababa, Ethiopia. The transmission is non-directional and typically has a power rating of 100 kW. Reception improves markedly around the 30 minute mark in the recording.
At 1900 UTC China Radio International's blowtorch signal eclipsed Radio Fana's transmission, so I continued exploring the nearby frequencies. By chance, I stumbled across an English news bulletin from the Voice of America on 6080 kHz that alluded to what Radio Fana had just been reporting in Oromo (namely, the unrest in the Somali province of Ethiopia that resulted in the resignation its regional leader):
After listening to this news bulletin I decided to jump across to the 31 meter band and quickly found myself listening to this rather nice song on All India Radio's National Channel on 9380 kHz:
After spending the past few months mostly recording portions of the shortwave spectrum outdoors with my various software defined radios I had forgotten how much fun it is to use the Tecsun PL-680 radio, the sensitivity of which easily rivals that of most of the SDRs I have used so far. I'll be sure to use it more often to discover what's happening on the bands while I'm making outdoor spectrum recordings.
All India Radio, recorded outdoors on 11560 kHz in London, UK on 31/07/18 at 1658 UTC with GPDWin, AirSpy R2, SpyVerter 2 and Bonito GI300 and Bonito MA305 portable active antenna. Audio only:
Radio Japan, recorded outdoors on 15445 kHz in London, UK on 06/08/18 at 1833 UTC with GPDWin, AirSpy R2, SpyVerter 2 and Bonito GI300 and Bonito MA305 portable active antenna. Audio only:
Radio Oromiya (Ethiopia), recorded outdoors on 6030 kHz in London, UK on 11/08/18 at 1856 UTC with Gole1, AirSpy HF+ and Sony AN-LP1 portable active loop antenna. Audio only:
The Ghoul (UK pirate station), recorded outdoors on 6316 kHz in London, UK on 11/08/18 at 1902 UTC with Gole1, AirSpy HF+ and Sony AN-LP1 portable active loop antenna. Audio only:
Channel Africa recorded outdoors in London, UK on July 31, 2018 at 1700 UTC, on the frequency of 11885 kHz using GPDWin, AirSpy R2, SpyVerter 2, Bonito GI300 isolator and Bonito MA305 active antenna. The transmitter is located in Meyerton, South Africa. This transmission had a power rating of 500 kW and was directed towards Central and West Africa. The recording contains a news bulletin discussing contested election results in Zimbabwe and Mali.
Radio Japan in English recorded in London, UK on July 26, 2018 at 0500 UTC, on the frequency of 9860 kHz using, SDR#, AirSpy Mini, SpyVerter and DX Engineering NCC-1 phaser connected to two Wellbrook ALA1530S+ antennas (positioned indoors) to mitigate severe local man-made interference. The transmitter is located in Santa Maria di Galeria, Italy. This transmission had a power rating of 250 kW and was directed towards West Africa.
The recording contains the news bulletin announcing the execution of the six members of a Japanese doomsday cult, Aum Shinrikyo (including its leader, Shoko Asahara -- real name Chizuo Matsumoto), who were held responsible for the deaths of dozens of people.
Below is a 30 minute recording of a Digital Radio Mondiale transmission from Radio Kuwait. Roughly speaking, DRM broadcasts are the shortwave (long distance) equivalent of DAB radio, where the audio is encoded digitally to save bandwidth, and — in the case of DRM — improve audio quality. This DRM stream was decoded from an outdoor spectrum recording made on 20/07/18 at 1830 UTC using my ultra-portable spectrum capture set-up. The program starts with the news, followed by western pop music. The video contains diagnostic information in the form of the DRM signal-to-noise ratio (SNR) and dropped audio frames. Although DRM broadcasts are usually more challenging to pick up than their analogue counterparts, I would classify this reception as excellent.
This post breaks with tradition in that the news events it mentions are listed backwards in time. The post is a collection of recordings I made off shortwave, reflecting significant milestones in the North Korean nuclear crisis to date. The recordings were made between September 3, 2017, when the DPRK conducted its sixth and most powerful nuclear test to date, and June 13, 2018, when the North Korean state media reported the meeting between Kim Jong Un and the 45th US President, Donald Trump, one day after the event.
13/06/18: North Korea finally reports the meeting between Kim Jong Un and Donald Trump
Voice of America's news bulletin, captured immediately following the above broadcast. 15580 kHz recorded outdoors in London, UK on 13/06/18 at 1400 UTC using a Tecsun PL-310 radio and a clip-on long wire antenna.
12/06/18: the North Korea summit in Singapore — the world media react (apart from North Korea)
Below is a 50 minute recording of a music programme broadcast on China National Radio's Kazakh service (a.k.a. CNR channel 17), consisting entirely of Kazakh songs.
The other day, while recording portions of the shortwave spectrum out in the park, I stumbled across a faint Voice of America broadcast in Somali with lots of music, which I rather liked.
Below is the full recording for your listening pleasure. Voice of America (Somali), recorded outdoors on 15620 kHz, on 30/12/17 at 1325 UTC using AirSpy R2, SpyVerter 2.0 and a 2x6m dipole.
Hello and Happy 2018 to all the readers of the London Shortwave blog!
This post comes after a relatively long hiatus, as new work commitments starting last summer reduced the amount of time I could spend on shortwave radio listening. Longer working days and commute periods gradually encroached on the time slots that I had previously allocated for going to the park to record parts of the shortwave spectrum. (On the other hand, owing to continuously increasing urban RFI, my indoor reception conditions have deteriorated to the point of being essentially unsuitable for any serious radio listening).
However, just as I found myself under these new time constraints, my friend Thomas Witherspoon contacted me to tell me about his new initiative, The Spectrum Archive, and kindly invited me to become part of the team (which I gratefully accepted!). From the project website:
The Radio Spectrum Archive (RSA) allows listeners to experience radio history as it happened. It offers listeners the ability to tune through a radio band, listening not only to individual stations, but to all the stations in broad swathes of recordings, providing richly relevant radio context from the time.
[...]
The Spectrum Archive team actively creates new spectrum recordings and maintains existing spectrum recordings for current and future use by, among others, historians and researchers.
The opportunity to contribute to this unique project renewed the impetus for me to find a way to create outdoor shortwave spectrum captures on the go without having to make return trips home to drop off my relatively bulky recording equipment.
PocketCHIP and FunCube Dongle Pro+ (September 2017)
My first attempt at this was to use the PocketCHIP portable computer and the FunCube Dongle Pro+, together with the Sony AN LP-1 foldable active loop antenna:
The idea was to have a spectrum capture set-up that could fit into the side pocket of my laptop bag and be quickly deployed in any open space.
PocketCHIP runs Linux, for which there are plenty of SDR applications, however, because of CHIP's limited CPU capabilities it is difficult to get any of them to run glitch-free. As a result, it's possible to inspect the spectrum visually prior to starting the recording but it's impossible to do both at the same time and there is currently no way of monitoring the audio while the recording is underway.
On Linux, FunCube Dongle Pro+ can be accessed without any SDR application running in the background (a big advantage given PocketCHIP's limitations): the dongle uses the sound card I/O interface and a simple audio recording utility such as ecasound can be employed to record the I/Q data stream to disk. However, the main drawback of this dongle is that it can only capture 192 kHz at a time, making it impossible to record an entire shortwave band in one go. On the other hand, PocketCHIP's battery life is around five to six hours, far longer than that of any of my laptops or tablets.
GPD Win and AirSpy HF+ (November 2017)
In November I received a sample of AirSpy HF+ — a very sensitive, compact SDR, capable of recording an entire shortwave band in one go. I used it to form an alternative ultra-portable capture set-up: the antenna is still the Sony AN LP-1 compact loop but the PocketCHIP is replaced with a similarly-sized GPD Win: a fully functional 5-inch (!) Intel PC running Windows 10:
AirSpy HF+ is tightly integrated with SDR# — a Windows application — which ended up being the main rationale for getting one of the most portable Windows computers out there and putting it to the test. After a bit of tweaking and experimentation (which I'll describe in detail in one of my next posts) I managed to get it to work. GPD Win's CPU is capable of running SDR# without any problems, its battery lasts around 4 hours when recording the spectrum and the Sony loop antenna proved to be very sensitive indeed:
The above two recordings were made with the GPD Win / AirSpy HF+ / Sony loop combination on Christmas eve in a London park, and the quality easily rivals that of the captures I have made with my regular outdoor set-up under similar propagation conditions.
I hope the greater portability will allow me to continue making outdoor spectrum recordings under increased time pressure. Thanks for reading and wishing you all a great year with lots of interesting radio catches!
GPD Win, AirSpy HF+, Bonito GI300 isolator and the Sony AN LP-1 loop antenna preamp out in the field
This blog was started on a hot and sunny afternoon in July 2013, while enjoying listening to some distant signals with a Roberts R9962 shortwave radio.
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