When HF collects new power for the autumn season, it’s time to thrown an ear onto VHF. I did so in May 2020, and the spectrogram at the top should give you an impression of the power and glory with with Sporadic-E fills the ORT band and the FM broadcast band. Having published some audio examples from both bands in the two recent posts, I now want to make some comments on this exciting propagation mode.
One signature of Sporadic-E is a highly selective propagation in respect to geographical regions – resembling a laser pointer. Please find below an example of just 90 seconds on 93.9 MHz on 29May2020, around 18:00 UTC (the vertical interruption at the last quarter of the audio spectrogram. It starts with a powerful-modulated, yet unidentified, Italien station with pop music. Then, Radio Constanine from Kef El Akhal (per RDS 2425) takes over with a distinctive (lower) sound, gevoerning the channel for a time, until the Italian comes through again. If play the audio clip and following its spectrogram in parallel, you surely will see what I mean.
Parallel listening on two channels is an essential tool to identify the same station on different channels. Place one (e.g. the left) audio channel on one frequency, and the other audio channel with a 2nd RX on the other (in this case: right channel). This can be done easily with SDRC V3 software. There will always be a time lag between both channels for at least two reasons: the main reason is that two frequencies are usually coming from two different locations, fed over different lines from the studio which causes a slight time difference. The other reason: different RXs in SDRC V3 software ore not phase-synchronized, so there is a small difference. Another difference might occur from different propagation time from two locations (300 km = 1ms!).
The screenshot below shows a typical setup: on 87.7 MHz a station in Arabic was heard. It was set onto RX1/left audio channel. To identify this station, RX2 was set to the right audio channel. Leaving RX1 on its frequency as the reference channel, RX2 was tuned to other channels with Arabic programme. The first hit was made on 87,6 MHz, second on 90,8 MHz, third on 92.5 MHz – all carrying the same programme. Hence, it was very likely SNRT Al Idaa Al-Watania from Morocco from four different locations at distances from 2312 to 2613 km.
The Radio Data System RDS provides an identifcation and often some additional information. First, you see the “Programm Identification Code – RDS-PI”. This is used to support an automatically scan of the receiver to tune always the best channel of this programme. Hence, it designates a programme which is used throughout a chaine of programmes. The “Programme Service Code – PDS-PS” needs a bit longer and gives, if programmed, additional information. As the RDS signal sits on edge of the channel and is quite slow, it is a bit delicate to receive from weak stations under interference. The first example below gives a full-blown RDS signal from a local broadcaster, followed by some RDS signals from DX stations.
Fading can be nerve-wrecking. Stations come and go. And they reliably go at top of the hour when the listener expects a station identification … Below I compared the signal from a still near-regional transmitter at a distance of 83 km with that of Radio Constatine/Algeria, 1802 km away. The grey block marks the limit, whre Radio Constanine can be demodulated.
Again, Sporadic-E reception. Now some examples from the FM Broadcast Band (87.5 to 108.0 MHz), as received in spring 2020 at my location in Northern Germany. See my former post for examples from the OIRT FM Band.
Non-official radio stations always attracted shortwave listeners who call them “clandestines”, follwing a mixture of mis-understanding and romanticism. The range of this class of stations is remarkably wide. Nowadays, the majority of them is renting time from major transmission centres like Nauen/Germany, Issoudun/France or Toshkent/Uzbekistan.
As all media, they are put into service to influence people and to sell something by propaganda. The difference between an official broadcaster, like Voice of America, and a “clandestine” like North Korea Reform Radio is not palpable – both are financed by the U.S. Congress.
With most broadcasters transmitting on a scale between facts (“white” – nearly only the BBC) and sheer disinformation (“black”), clandestines are placed on the darker third of this range. The separation between “clandestine” and “official” is rather artificial. There simply is no difference between e.g. the official World Harvest Radio and the clandestine Voice of Wilderness, both religious brodcasters, funded by Cornerstone Ministries International/USA – to take just two religious stations.
Today’s activity of clandestines is concentrated on Africa and Asia with especially taking countries like North Korea, China, Eritrea and Sudan into focus.
Some clandestines are jammed, mostly by official broadcasters of the target countries with more or less their usual broadcast; rarely by transmitters just carrying noise.
All known clandestines are official in the sense that the government of the transmitting country knows about their activity and, tacitly at least, is endorsing it. More often than not, clandestines are simply the grey/black arm of their governmental propaganda, like the South Korean “Echo of Hope”, presumably maintained by a (however, non-existing) “General Union of Overseas Compatriots” which in fact turned out to be the South Korean National Intelligence Service NIS.
If you want to look behind the veil, just “follow the money”. In most cases you will land at the U.S. Congress (see illustration below) or some other governmental entities of a third country. Yes, also take care of NGOs, as some (not all) of these “Non-governmental Organizations” are funded by – nothing more but governments of a third country; a system much reminding to money laundering or the game “three shells and a pea”.
The overwhelming number of clandestines orignates from “the West”. You can play bullshit bingo with their names or the names of their funding organizations containing: “freedom”, “democracy” and “independence” at the least. That they are running under false flags, gives the right impression of how some kind of journalism works in “the West”.
The authoritative World Radio TV Handbook has an own section of “Clandestine and other target broadcasts”. Please find below some examples out of their 2020’s edition (pp. 509) plus some examples following my a bit wider definition of a clandestine station: each station, which intentionally disguises their source. So you will find Azadradio, but not “Voice of America/VoA Deewa Radio”, although both are financed by the U.S. government.
All stations had been received between December 2019 and April 2020 in Northern Germany. Their reception quality, of course, is very different; for some of them you should put your headphones over.
The following 27 audio clips, appearing in their target countries’ order (or, the country to/against which people/government their transmissions are targeted), were made from wide-band HF recordings with Winradio’s Über-SDR Excalibur Sigma, connected to MD300DX antenna, an active dipole, hung vertical, with 2 x 5m legs; software: SDRC V3.
P.S.: I know, you must not scroll. But please allow me for an expcetion in this case.
AFGHANISTAN Azadradiowith their headquarters in Kabul is a branch of RFE/RL, a mouthpiece of the U.S. government. Transmitting towards Afghanistan in Pashtu and Dari.
AZERBAIJAN Voice of Free Talyshistan is transmitted by the Modus Vivendi Center, based in Yerevan/Armenia. Chairman of this non-governmental organization is Armenian lawyer, historian and diplomat Ara Papian. In an interview with TERT [an Armenian media] he supports Armenia’s president that “[land-locked] Armenia must divide [oil-rich] Azerbaijan [at Caspian Sea] as a political unit, cooperating with stateless nations”. One of this “stateless nation” are the Taliysh people, representing 1,4% of the people of Azerbaijan. Hence, Voice of Free Talyshtan is an instrument to separate a future and Armenia-friendly “Talyshistan” from Azerbaijan.
CHAD Radio Ndarason Internationale is based in N’djamena, the Chad’s capital. It is aimed to the people in the Northern Nigeria and Chad region and is directed against the islamic Boko Haram network. The programme is produced by Johannesburg-based Okapi Consulting, a “media consulting agency”, maintaining no less than five radio stations. Radio Ndarason is aired by BBC transmitters from Wofferton/UK and Ascension.
CHINA  [among others] Radio Free Asia was founded by the US Congress and is financed by the USA as part of their foreign policy. Part of its task is to encourage separating movements – e.g. in China with transmissions in Tibetian and Uyghur; the common pattern of this kind of stations, see also the Azerbaijan entry above.
Sound of Hope with headquarters in San Francisco/USA, is the broadcasting arm of Falun Gong. This organization covers a wide spectrum of religious, economical and political fields. It is controversly debated over in the West as in the East. In China, it is forbidden. SoH uses a couple of more or less low-power and frequency-agile transmitters from said locations in Taiwan; also Thailand is rumored. By errors in switching the audio onto a transmitter, I heard also the sound of Radio Free Asia’s Mandarin channel on some of their 100+ frequencies. China performs cat-and-mouse games to place one of their much more powerful transmitters on some of SoH’s active and ever-changing channels. Sound of Hope usually transmits some ±100Hz off nominal channels and also often outside the brodcasting bands to evade jamming. Funding is done by Falun Gong plus, presumably, also by the U.S. government via their USAGM.
CHINA  Voice of Tibet is producing from Dharamsala/India and promotes Tenzin Gyatso (Dalai Lama), living in exile in just this city. He himself considers the radiostation, as it “… allows us Tibetans to comment on events of Tibetan interest from our own perspective”. Voice of Tibet is funded by a Norwegian charitable foundation (Stiftelsen Tibetprojekt). It is mostly transmitting ±1 kHz off an designated channel.
Radio Televisión Martí is produced by the Miami-based Office of Cuba Broadcasting, a branch of the U.S. Agency for Global Media, USAGM. This, in turn, is part of the U.S. federal entity “Broadcasting Board of Governors” – the usual matryoshka concept of a puppet in a puppet in a puppet, all firmly hanging on the strings of their government. They mention “democracy”, “independant”? Bingo!
ERITREA Radio Erena is produced by Eritrean journalists in Paris and is supported by by Reporters without Borders.
Radio Fardawith their headquarters in Prague/Czech Republic is a branch of RFE/RL, a mouthpiece of the U.S. government. Transmitting towards Iran in Farsi.
KOREA [North]  Furusato no Kaze/Ilbon-ui Baram is officially brodcasted by the Japanese Government “to Japanese people who have abducted by North Korea and are still trapped in North Korea”. They are the same stations with Furusato no Kaze (Wind from the Homeland) is broadcasting in Japanese, whereas Ilbon-ui Baram (Wind from Japan) transmits in Korean. Both IDs are presented by each an audio clip.
Korea [North]  Voice of Wilderness is produced in Seoul/Korea by the religious organisation Voice of Wilderness Ministries, based in “Tamil Nadu/South India”. As far as I understood their sermon, they believe in “a second coming of Jesus” – excactly the problem, that mankind and especially the targeted people in North Korea are interested in most. They seem to be affiliated to Cornerstone Ministries/USA and Korean Reconciliation Initiatice and Network, wanting to “restore the church” in North Korea.
Korea [North]  Echo of Hope claims to be produced by the otherwise non-existing “General Union of Oversea’s Compatriots” which is an echo of South Korea’s National Intelligence Service NIS, in turn being an echo of the South Korean Government.
Korea [North]  North Korea Reform Radio maintained by the so-called NGO North Korea Development Institute which in financed by the U.S. foundation “National Endwonment for Democracy”, funded by grants from the U.S. Congress.
Korea [North]  Voice of the People, operated by the South Korean National Intelligence Service by another yet unknown organization, dubbed “Korean Workers Union”.
NIGERIA Dandal Kura Radio International, funded by USAID, an organization under the US Department of State. It is aimed to the people in the Northern Nigeria and Chad region and is directed against the islamic Boko Haram network.
PAKISTAN Mashaalradio with their headquarters in Prague/Czech Republic is a branch of RFE/RL, a mouthpiece of the U.S. government. Transmitting towards Pakistan in Urdu.
RUSSIA [among others] Radio Free Europe/Radio Liberty, now only a shadow of itself, was in nearly all aspects a role model of this kind of propaganda radio. Founded in 1949/1953 by an organization fully funded by the CIA (until 1972), it played a major role in Cold War’s “War with Waves”. It remains an United States Government-funded media agency until today with still a few outlets on medium wave and HF, covering East Europe as well as Russia, Iran, Central Asia, Caucasus, Southeast Asia and the Balkans.
SOUTH SUDAN  Eye Radio is operated by Eye Media Ltd. and was/is supported by USAID, an organization under the US Department of State.
SOUTH SUDAN 
Radio Tamazuj is produced by the organization “Free Press Unlimited”, which is largely (89%) funded by the government of the Netherlands. Additional 8% of the budget comes from the Dutch Postcode Lottery. Targetting the people on both sides of the border between South Sudan and Sudan.
SUDAN Radio Dabanga is produced by the organization “Free Press Unlimited”, which is largely (89%) funded by the government of the Netherlands. Additional 8% of the budget comes from the Dutch Postcode Lottery. Targetting the people on both sides of the border between South Sudan and Sudan.
TURKEY [among others] Radio Dengê Welat is the third metamorphosis of what started in 2012 as Radio Dengê Mezopotamya, to be changed fived years later into Radio Dengê Kurdistanê. It transmits in four Kurdish dialects to Kurdish people. Their headquarters are said to be in Belgium in Denderleeuw near Brussels. It is backed by Uppsala-based Stiftelsen Kurdisk Media.
YEMEN [and others] Radio Al-Azm is a branch of the Saudi Arab Broadcasting Authority with their programme aimed to Saudi military personnel in southern Saudi Arabia and Yemen
Okay, the birthday flowers are already letting hang their heads – but better late than never: Happy birthday, Radio Xinjiang, XJBS!
It was founded in the same year as the People’s Republic of China itself. Only the 1957 edition of the authorative World Radio Handbook took a first notice of their shortwave transmitters at Ürümqi. One of these frequencies, namely 4500 kHz, is still active today.
Among DXers, Radio Xinjiang is a welcomed signal from their transmitters at Ürümqi-Hutubi and at Ürümqi-Changii, some ten kilometeres northwest of Xinjiang’s capital Ürümqi, all in the north-west corner of China.
XJBS’ shortwave transmits in Uighur, Kazakh, Mongolian and Mandarin (“Chinese”) to serve the majority of listeners in each their mother tongue. Please find below their station’s announcement in each of those language. I especially like the “Nĭ hăo, Xinjiang” of the Mandarin recording at second 20. The announcer must have seen Good Morning, Vietnam, undoubtedly echoing Adrian Cronauer [the late Robin Williams]. Just for conaisseurs: in the YouTube clip, Adrian mentioned “Hanoi Hannah”, or Trịnh Thị Ngọ, a popular radio announcer at Radio Hanoi from 1965 airing three shows per day in English, directed towards US GIs. She left microphone only in 1973, after the USA fled from her country.
The following audio clips from my 25MHz/24h recording of December 16, 2019, received with Winradio’s Über-SDR Excalibur Sigma, connected to MD300DX antenna, an active dipole, hung vertical, with 2 x 5m legs.
I will come back to this interesting station with an analysis of their alltogether 24 HF frequencies between 3950kHz and 13670kHz here in Northern Germany in December 2019, as well as in early April 2020.
P.S. Below a QSL of this station, from 1984 on 4735kHz.
The news about the death of HF Broadcast are greatly exaggerated. The map on the top presents 574 active stations, scattered all over the world. This interactive map has been made with free Tableau Public software: simply click onto the map, an in another tab of your browser it pops up. Now you can point your mouse to a mark and see some data.
There even is more: as some transmitting sites are used by several broadcasters, this fact is shown by different colors. Your mouse will tell.
The best thing of this map is the fact that it is strictly geo-referenced. If you zoom into a station, you should directly see the transmitting site form above – depending, of course, from the resolution of the underlying OSM satellite map.
After having scrutinzed all sources (HFCC, WRTH …) available, I finally decided for ILGRadio. Only these data are concise, complete and precise – a great achievement of Bernd Friedewald since decades! [To keep things simple, only one transmitter’s power is noted for each site]
This map, together with ILGRadio (see below), works as a promising starting point of future work, e.g. band scans in the light of the 21st century …
IRAN INTERNATIONAL is transmitting in Farsi via their relay station just at the outskrits of Uzbekistan’s capital, Toshkent, with 100kW on 6270kHz from 12:00 to 04:00 UTC, directed towards Iran.
I received this station in winter as in spring. In winter (namely 16DEC2019), the whole transmission from sign-on to sign-off can be received, wheras in spring (namely 02DEC2020) a considerable part of the transmission after sign-on has been lost in the noise, plus the time towards sign-off in the morning largely coinciding with fade-out; though still celarly visible.
You see also a clear greyline enhancement at least on the fade-in. Sunrise and sunsetset for both locations can be seen from the bar chart below in the diagram..
The graphs are based on 2 x 86’400 points each, providing a time resolution of one second. To make things more clearly, the bold blue and yellow lines represent a smoothed version (moving average: 601).
This is just one example of how the actual signal strength of a station differs from season to season. With 24 hours’s recordings of the whole HF on both dates, it is easy to compare also other stations and frequency ranges. If I have time, I will add some more examples in the future.
BTW: I passed the big transmission center southwest of Toshkent left-hand, riding M39 on the way to Samarkand; it was not encouraged to take any photos …
The evening transmission of the Voice of Broad Masses from Asmara-Selae Daro in Eritrea signs on around 14:06 UTC and signing off around 18:30 UTC. Figure 1 shows the signal levels with a resolution of one second, marked by red points, and the smoothed level, yellow line, with a moving average of 601 points, or 10 ten minutes. Smoothed levels span a range from -106 dBm/Hz to -80 dBm/Hz.
There occur considerable peaks around 14:30 UTC, 16:15 UTC and 17:30 UTC. Raytracing the signal, transmitted by a Quadrant antenna HQ1/.25, will help to reveal some mechanics behind the curve.
Figure 2 shows a four-hop propagation via F1 layer at 140-160km with a relative steep elevation of about 22°. The much shorter hops, reflected at the E-layer at a height of about 100km, are of less to no importance. The signal gets through, but very weak. The path itself still is in full sunshine, see Figure 3.
There is a very short, but distinctive peak at 14:30 UTC. This coincides with a similar short time of three-hop propagation (Figure 4) from a very low azimuth of 3°. Of course, the full path still is in daylight.
Just after 16:30 UTC and near sunset at the transmitter (16:37 UTC), there is reached the bottom of kind of a “Hillary Step” before the last run to the peak. The way to a (quite short) plateau starts around 17:00 UTC. There we have a textbook-like two-hop propagation (Figure 5) with the greyline covering just more than half of the great circle path (Figure 6). There, an elevation of under 5° is needed.
Propagation on HF differs from day to day. The nine diagrams at the top show the signal strengths of China Radio International’s Kashi transmitter, 500 kW, beaming to Romania; 08:58 UTC to 09:58 UTC from March 15 to March 23. The basic resolution (black grey points in the background) is 100 milliseconds, whereas the blue line marks the moving average with 601 points. The “moving average” can be best understood as a lowpass filter, revealing possible trends on a coarser scale. In this case, you cannot see such a trend.
If you compare a part of each transmission on a much finer scale, you even see sheer chaos, as the Figure below is showing:
There seems to be no visible correlation on any scale in this case. There are other cases where, however, some correlation can be found – to which I will come back in some future entries.
The last diagram at the bottom of this pages shows a much more forgiving picture of the signal: the average level changes not more than ±4 dB between best and worst days. This so-called box diagram illustrates best the actual receiving quality of the broadcast, demodulated with an synchronous detector to largely avoid severe distortion by selective fading. The difference of deciles 90% and 10% marks the fading range, a key figure in describing the quality of reception – see “Ionospheric Radio” by Kenneth Davies [London, 1990/96, pp. 232].
Analyzing signal strenghts, is an interesting tool to get to know more about propagation. I will continue this topic – stay tuned!
Today’s SDRs plus able software allow for some new insights into propagation. The figure at the top shows but one example: greyline enhancement. It follows the signal levels on 4750 kHz with a resolution of one second. Smoothing this cloud of points, reveals the more general course of signal level. Here we see, after sign off of Bangladesh Betar, the 10 kW transmitter of People’s Broadcasting Station at Hulun Buir coming up. Most interesting is its short-living enhancement just after sunrise at Hailar in China’s Inner Mongolia, squeezed at their borders to Russia and Mongolia.
This greyline enhancement can be observed regularily on frequencies under, say, 10 MHz: at sunrise at the transmitter’s site, first the F2 layer of the ionosphere is building up, being responsible of the signal of, here, about 5 dB. The lower and attenuating D-layer needs a bit more time to build up, leaving a short-living window for an enhanced signal.
This is to encourage also other HF aficionados to to use this technique.
With some iteration, as described in the PDF, the former unknown site of a CIS-12 transmission on 6.465 kHz has been disclosed as the Russian Navy from Baltysk, Kaliningrad.
The stunning direction finding tool on the KiwiSDR net has hit the community. Most people are enthusiastic about the new horizons, some some smart people had opened for free.
A few people, however, reported some disappointment as they couldn’t pinpoint each and every transmitter with expected high precision.
To avoid this disappointment, you have to know what you are doing. The TDoA tool for direction finding indeed delivers automatically stunning results. But you have to think a bit about the setup, and also do some iteration.
I wrapped up my first experiences with TDoA in this PDF. You may simply download it by double-clicking the link, and open it in a PDF reader. It consists of 22 pages and 37 instructive figures. I greatly stressed the practical part of direction finding with this tool – with 13 explicit case studies from 2,6 MHz to 15,6 MHz.
The idea is to have more fun by getting the most reliable results.