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DXpedition retrospective: Singapore 2019

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Wednesday, June 17, 2020
Marina Bay Sands, Singapore. © 2019 London Shortwave
In August 2019 I visited Singapore, where I was able to test a pre-release sample of the AirSpy HF+ Discovery SDR, kindly sent to me by Youssef. Due to a very busy schedule I was only able to make two short outdoor radio recording trips, amounting to three hours in total. Needless to say, the advantages of portable shortwave spectrum capture manifested themselves fully in these hurried circumstances. I made these two trips on August 27th and 29th and I shall start with the latter outing as that was when I made my most prized recording to date.

East Coast Park, 29/08/2019


Spectrum capture QTH on 29/08/2019
East Coast Park is Singapore's largest and occupies 15km of the island's coastline. I chose this location because it was easily accessible and not particularly crowded on the day:


My recording set-up consisted of the GPDWin 5" mini-computer running Windows 10 and SDR# 1631, AirSpy HF+ Discovery and a long wire antenna:


I arrived at 1723 local time (0923 UTC) and after experimenting with reception on different bands for about an hour I settled on the 49 meter band and started recording it just before 1100 UTC (after grabbing a coffee from the large Starbucks situated right behind me). An hour later, as the beach became dark and windy, I packed up my equipment and went back to the hotel. Later that night I reviewed the spectrum capture file and the very first station I stumbled upon was one that had eluded me since I returned to the shortwave listening hobby in 2013: Myanmar Radio.

Myanmar Radio QSL card. Image from Pavel Zhuravlev
Below is a one hour recording of this station extracted from the spectrum capture. It contains a mixture of talk, traditional songs and national rock music. The 50kW non-directional signal on 5915 kHz  is listed as "Myanma Radio Naypyidaw Service in Minority Languages", although I have not been able to establish the exact language of this broadcast. Some time ago one Shortwave Radio Audio Archive contributor said that "this may be one of the most exotic countries still left on shortwave". I agree!


Radio New Zealand International (RNZ Pacific)



I have a special fondness for RNZI as it was my first bit of long-distance DX back in 2013 when I was staying in the Russian countryside. Receiving this station in Singapore would always have been a lot less challenging but it's still nice to hear this old friend from the Pacific on the airwaves, especially as it has been a harder catch in Europe in recent times. Below is a one hour recording RNZI's signal extracted from the spectrum capture file.



KCBS Pyongyang


This is the domestic arm of the North Korean radio service, which regularly makes it into Europe on 9665 and 11680 kHz (almost always faintly) but far less often on this 6400 kHz frequency. From NorthKoreaTech:
The Korean Central Broadcasting Station (KCBS) (Korean: 조선중앙방송, Chinese: 朝鲜中央放送, Japanese: 朝鮮中央放送) is the main domestic radio network in the DPRK. It sits under the Central Broadcasting Committee of the DPRK (called the Radio and Television Committee of the DPRK until 2009). 
KCBS broadcasts from 5am to 3am local time via a network of medium wave and shortwave transmitters that cover the nation. The powerful transmissions can easily be heard in neighbouring countries, including South Korea where some of its frequencies are jammed. 
A central program is broadcast from Pyongyang on most transmitters through the entire broadcast day, but some are reported to carry regional programming between 2pm and 3pm.
Below is a one hour recording of this signal. Note the militant style of the radio presenter and the rousing patriotic music.  There were lots of other North Korean transmissions available during both of my outings but I will avoid repetition here.



Echo of Hope


South Korea's clandestine counter-broadcast on shortwave, beamed into North Korea from Hwaseong but picked up very clearly in Singapore. There isn't much information available on this broadcaster online, although apparently a few listeners managed to obtain the station's QSL cards via South Korea's international broadcaster, KBS World Radio. Below is a one hour recording of their signal.


VMW Marine Weather Station, Wiluna, Australia


Australia Marine Radio Broadcast Areas. Source: The Australian Bureau of Meteorology
The Australian Bureau of Meteorology broadcasts marine forecasts and warnings to mariners over shortwave from Charleville (VMC) for eastern waters and Wiluna (VMW) for western waters. The transmitter specifications for the VMW broadcast state that it is powered at 1 kW (presumably non-directionally, based on the map above) and according to the schedule the forecast recorded below was supposed to be for Western Australia (Northern Zones: NT-WA Border to North West Cape) and the Northern Territory. This signal occasionally makes it into Europe in winter but I've not yet managed to pick it up in London.


Radio Nikkei 1


Radio Tampa QSL card from the late 70s. Source: kusanagi1965
Radio Nikkei 1 (Radio Tampa until 2004) is a nationwide commercial shortwave radio station in Japan, operating from Chiba-Nagara at 50 kW since 1954, and was another first catch for me. Wikipedia's description makes it sound like a fairly unique station in today's shortwave world:
The station features the following four genres as the core of its programming: finance, JRA horse racing (weekends), health-medical, and culture.
Below is a one hour recording of the station's 6055 kHz signal extracted from the spectrum capture.


Voice of Vietnam National Channel 4

This is one of Vietnam's many domestic shortwave services, broadcasting non-directionally at 20 kW from Đắk Lắk and yet another first for me. Below is a one hour recording of this station extracted from the spectrum capture file.


BBC World Service transmitting from Kranji, Singapore


Kranji transmitting station. Source: Google StreetView
Amidst all of this DXing fun it would perhaps be easy to forget that Singapore is home to the Kranji transmitter site, which several international broadcasters use to reach listeners across South-East Asia. My QTH in East Coast Park was merely 20km away from Kranji and the video below clearly shows how strong the local 125 kW signal of the BBC World Service was on that day. The most surprising part was just how well AirSpy coped with having that monster signal next to all the weak transmissions I extracted above: at no point did it look like the ADC was anywhere near its saturation point. If I had more time I would have tried to visit Kranji and check out the transmitters; I hope to do so during one of my future trips to this country.


Pasir Ris Park, 27/08/2019


Spectrum capture QTH on 27/08/2019
Two days earlier I visited Pasir Ris Park on the other side of the island. The park is located right next to Singapore's Changi Airport. It's a great location for DXpeditions because overnight camping is allowed, albeit only with a permit obtained via the National Parks Board's website (something that I would also like to do during my next visit).


I arrived at the recording spot at around 1830 Singapore time and started capturing the 25 meter band 90 minutes later (at 1200 UTC). In retrospect this wasn't the most interesting band to record as it was mostly populated with services from China Radio International and China National Radio, which you can hear pretty much anywhere in the world. However, I did manage to extract a few interesting transmissions:

View from the recording location towards Serangoon Island. © 2019 London Shortwave

View towards Changi Airport approach. © 2019 London Shortwave

Voice of Vietnam's English language service to South East Asia and the Pacific


I have made many recordings of the Voice of Vietnam's English language broadcasts, which can be heard in Europe on 7280 and 9730 kHz at 1600, 1900 and 2130 UTC. What I didn't realise before catching this particular transmission is that the content of the international news bulletin depends on the region to which it is being broadcast. The European transmissions I pick up in London are typically focused on Vietnam-EU and Vietnam-US relations, while in the recording below, the news is Asia-Pacific-centric. To me, this shows that the Vietnamese government still take their shortwave operations seriously.


NHK World Radio Japan



NHK World is the international arm of the Japanese state broadcaster, NHK. The one-hour transmission below was beamed south-west in Japanese out of Ibaragi-Koga-Yamata, at a mighty 300 kW. Perhaps this was the next easiest signal to catch after the BBC World Service out of Kranji, but the reason I include this recording here is that by coincidence I stumbled upon the relay of ABC-Z's weekly program on NHK Radio 1. ABC-Z are a popular Japanese boy band who have been active in under various guises since 2001. You can catch their songs at 18:40, 36:26 and 50:48 in the recording below.

Members of A.B.C-Z


Republic of Yemen Radio (clandestine / Saudi Arabia)


Distance calculation by Google
Republic of Yemen Radio is a clandestine radio station broadcasting out of Saudi Arabia. It delivers programming reflecting the position of the Saudi-led coalition that participates in the ongoing Yemeni civil war. The precise location and power rating of the transmitter are not officially disclosed but are believed to be Jeddah and non-directional 50 kW, respectively. Given the 7,331 km distance to the transmitter site and the non-directional nature of the broadcast, this DX is still somewhat noteworthy.

Overall, I couldn't be happier with what I managed to capture with my portable SDR set-up in the limited time available. Although I wish I had spent more time on the lower bands, as that is where more of the local and exotic stations of the region reside, there's always the next time, and yet another reason to come back.

New Year, new endeavours: ultra-portable shortwave spectrum captures in 2018

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Monday, January 01, 2018
GPD Win, AirSpy HF+ and Tecsun PL-310ET
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