(Source: Radio World via Maichael Black)
Note that the excerpt below is only a portion of the full article. Read the full piece at Radio World.
Does Shortwave Have a Future?
by RUXANDRA OBREJA
When is the last time you heard a shortwave radio transmission? And why should you put up with possible crackly audio and some interference when we have now internet, satellites, FM and all forms of digital radio?
[…]Shortwave is just short of a miracle, actually. When it is beamed at an angle, it hits the ionosphere. A mirror around the Earth and then it falls like a ball at great distances, beyond the horizon. Thus these transmissions reach listeners over large areas, continents and beyond. Two or three high-power transmitters can potentially cover the entire world.
Shortwave is used not just by international radio stations or radio amateurs but is also essential for aviation, marine, diplomatic and emergency purposes. Shortwave signals are not restricted or controlled by the receiving countries and, as frequencies change in winter and summer, they need to be coordinated internationally.
[…]Digital Radio Mondiale was originally invented to offer medium (AM) and large coverage (HF) and the advantages of the good audio quality and extra multimedia services that can take shortwave into the 21st century. Maybe DRM was ahead of its time. The phasing in of digital broadcasts internationally was not in tandem with the production and sale of receivers, which remains a regional and national business. Since its birth DRM has proven that it is a suitable option for shortwave offering an good digital quality of audio and even short live video at great distance without fading and crackly sound.
Now, at last, there are DRM receivers capable of receiving shortwave, there are broadcasts and interested broadcasters. Quietly and surely shortwave is being re-examined and appreciated for the quality of broadcasts and its potential as a “crisis radio” too. It can become crucial in emergencies when local and regional radio stations, satellite and internet may be off the air due to damage. Broadband is getting cheaper but is limited, 5G will come but not just yet, digital shortwave is here.[…]
WARNING: long read ahead.
TLDR-version: the medium isn’t the problem, it’s the business model and format used that’s the problem.
I think DRM is a neat idea but the problem with it is that no one wants to pay the initial overhead that comes with changing from an analog system (simpler circuitry) to a digital one (more circuitry, so more costly). This is all while radio listening across the world is down. That’s not an error but rather a long term trend that will only get worse as long as the format of the medium remains the same. In theory, we could try to utilize HF for other purposes but it’s really a problem just with all media not willing to break from the mold of old formats. Just to give you example of how stubborn some companies are: CBS with it’s Internet only show Star Trek Discovery is released at a certain time in the week while Netflix and others have no problems dropping an entire season onto their services. That’s the kind of mindset plaguing radio as well. It’s a medium with an ossified business model and HF isn’t immune this problem. Like, I’d love to see short range (for HF) broadcasting along with some kind of data services being used with it. But it’s a royal pain in the rear to get any regulatory body to allow even a fraction of the spectrum to be used for such experiments. Imagine using 19 meter or higher for short range data services (tens to a couple hundred miles) that’s the kind of thing I think would revitalize the medium.
I would, actually, favour SSB over either AM and DRM in shortwave frequencies to reach maximum number of listeners. SSB can overcome much higher environmental noise levels and stronger jamming than either AM or DRM. In addition, SSB can deliver twice wider audio frequency range than AM when transmission bandwidth is kept unchanged.
I hope, future versions of dsp chips to have effective noise reduction techniques to further improve audio quality in reception of analog signals including AM and SSB.
As the balkanization of the Internet gets worse every day, people are looking back fondly at the shortwave bands as a way to get opinions and news in to countries that censor the Internet.
DRM on shortwave could be a component of that method. One of the funny things about a software defined radio is that they are inexpensive and that because they can use open source software they can be used to tune in any signal, regardless of where it is from.
The missing link is an easy to use piece of software that can run on a tablet or PC with common SDR platforms. That will do more to revive the DRM effort than anything else. But unfortunately, DRM was built upon proprietary codecs, so open source software is going to be a bit of a problem.
You just can’t win some days.
They can still do that. The radios still exist, and people can still transmit. It doesn’t work as well, though, because countries can and do jam signals if they have such a large problem with them. It is harder to censor the internet because you can’t find every single page you might have a problem with. The main things will fail, of course, but it is possible to get some information in and for people to relay that to others. Shortwave transmission is only available to massive enterprises, and as such does not offer many types of information. I’m sure it is helpful in many areas, but I don’t know to what extent people trying to deal with censorship are considering shortwave as a solution.
Wishful thinking from a biased source anyway.
DRM is a solution looking for a problem.
But the problem is that SW is about govts, not hobbyists in this case.
And govt’s aint interested anymore.
Radio China on DRM is only broadcasting to 5 listeners, all of whom are only interested in seeing if the
button marked DRM works, and not the content 😉
Eh, I bet Romania has a small cadre of listeners to their DRM broadcasts, and of course New Zealand has been using it with good success to feed FM transmitters on remote Pacific Islands; people can tune in directly to that as well, and I understand it often reaches the west coast of the US.
Kuwait may still be doing DRM to Europe and the Middle East, and Nigeria has apparently turned their DRM back on and it’s reaching northern Africa and Europe, too. WINB has been testing a low bitrate DRM broadcasts to Europe and the US with some good success. Now that RNE has expanded their Spanish programming and has re-introduced English language shows, I have hope that they may resume a DRM broadcast to the US at some point.
I think DRM has always been a chicken-and-egg situation. No one wants to broadcast in it because there are no radios, and there’s no market for expensive radios when no one’s broadcasting in DRM. Plus, it’s a product that debuted at the tail end of the hobbyist era of SW listening. Still, with the (relative) ease that anyone tech-literate can set up Dream DRM decoder on a PC and use it with a cheap SDR to get DRM, it seems that the number of possible listeners is now higher than ever (albeit still very small).
Of course, those of us in the US are just spinning our wheels anyway since no one is really targeting us anymore. And DRM is definitely a thing that only works in the target zones, it’s not for weak signal DXing. But for Europeans and Asians listening, it can work if the radios can be manufactured at a reasonable cost.
Well said Tom.
However, while the number of possible listeners is growing, the number of possible listeners in the target audience is not. Most shortwave outlets want their signals heard in places where things are less developed, and people lack the electrical, computing, or network resources to simply tune in an internet stream. Without a standalone and inexpensive DRM receiver, these people won’t be able to use it. Therefore, the places broadcasting to them won’t consider DRM. Not that this is every broadcaster, but it does account for almost all of the big ones.
Mobile devices are becoming very common in these places, even while data service remains expensive or unreliable. If a person has a mobile device, and it’s new-enough to have USB host capabilities, a RTLSDR based SDR is as cheap or cheaper than a comparable SWL portable. It’s currently very much a hobbyist platform, but If there was a polished, commercially available mobile-SDR setup like this, it could provide free and reliable SWL-sourced content to existing mobile devices. DRM audio and digital text bulletins would both work nicely with mobile phones.
Interestingly, if the content was there, a SDR plus a low-cost single-board computer and hard drive could decode everything off-air (within it’s bandpass), “DVR”/archive it, and provide it all, on-demand to a small community over WiFi. Even with a few broadcasters, it wouldn’t take long to build a significant library of content.
The only question is: is it easier/cheaper/better to just provide internet connections to remote areas than build/upgrade all that SWL infrastructure.
Yes, there’s this strange belief that “less developed” = “poor” & “can’t afford any tech”. And it’s even stranger when some of the proposals to change that situation boil down to “if you buy our system that requires $300 devices, we hope that someday in the future they will only cost $50”.
Doubly so if the long-established already-existing technology only requires $5 devices – or that can even be built for ‘free’ with a bit of scrounging and some applied learning/experience.
And triply so if you actually look around and see what’s happening in those places – they’re all, in their own ways, in the process of leap-frogging from “almost no tech” to “modern tech just a generation or two behind so-called ‘developed’ countries”, developing their own solutions based on devices that only cost $10.
The last thing they – any country really, developed or less-developed – needs is a different technology that hasn’t really managed to establish itself beyond novelty status anywhere else in the last 15 years. And people in developed countries really need to actually _look_ at what’s going on in those places now, instead of projecting and creating “solutions” based on their ficticious or out-of-date beliefs about how things are in “less developed countries”…
(Not picking on you specifically, Lawrence N or Jason – just some general commentary riffing on points you both mentioned.)
Now, don’t get me wrong. I like the _concept_ of DRM. I like to _listen_ to DRM. But it’s practically a case-study in ‘how NOT to roll out a new technology & create a market for it”.
In my previous comment, I said that broadcasters were targeting places without “the electrical, computing, or networking capability” for internet streams. Those places are not the ones that are dramatically modernizing, with connections to the internet becoming widely available. That type of leap forward is already being handled by the availability of internet streams, at least as the broadcasters imagine it. For anywhere where people have mobile devices and connections are strong enough to provide WiFi, internet streaming is just fine.
The locations where radio is more needed is where one or more of these things are lacking. There are some places where people do not have phones or other modern technology for the simple reason that they do not have power. Without electricity, it is difficult to charge a phone. You can do it, but it’s much more power-hungry than other devices. Also, the lack of power usually means that there is little or no infrastructure for cell connections, negating the utility of the device for communications. However, the larger subset of the original group is a place that has some power, enough to run a phone and phone network, but little network bandwidth meaning that internet streaming is not feasible from a financial or buffering perspective.
On the suggestion of a phone and RTLSDR combination, not a chance. A shortwave radio can be ridiculously cheap. The ridiculously cheap ones are not very good; they look like the pocket transistor radios of the 1970s, but they work. For an RTLSDR phone solution, you need:
1. The RTLSDR itself (must be one with shortwave in frequency range, 4x price of basic radio).
2. A connector to the phone (very cheap, but I don’t know if those are frequently sold in local places, given that if I want an OTG adapter here, I usually have to buy it online).
3. An antenna that works with the RTLSDR, because basic ones are very bad. The cheap radios have an antenna, again, not a good one, but it works. The RTLSDR may come with an antenna depending on what you buy, but it only really functions at higher frequencies. For shortwave, you’re lucky to pull anything through with it. You need another antenna that can be attached to the SDR.
4. SDR software. I don’t know if they have a free one yet. The only time I looked, admittedly about two years if not longer ago, there was only one that seemed to work, and it was relatively expensive for a mobile app.
Even after you have all these things, the resultant device is a cobbled-together system that requires a lot of power, can’t be powered externally from a battery or mains because the USB socket for the phone is taken, and definitely cannot be pocketed. The cheap radios have none of these problems.
Nobody – even the DRM consortium – seems to address the fact that no DRM receivers have been made practically available to consumers. The Gospell is a bespoke radio that is exorbitantly priced and has to be specially-ordered from China and gets lousy reviews; the generic DRM DAB+ model on the DRM site appears to be a slapped together job of questionable quality only available in quantities of 1000 from alibaba; the other two (especially the Titus) are pure vapor ware.
Sure, there are SDR solutions like the ELAD and other software, but that’s for serious hobbyists.
As far as getting an audience, DRM is a technology with none, and they aren’t doing much to change that. These supposed not-for-profit consortiums need to wake up and realize they actually have to do some work to get the technology into the hands of listeners around the world. DRM can talk about paradigm shifts all they want – until an average person can pick up a DRM radio for a reasonable price at a retailer – or decent quality radios are injected into emerging markets, DRM ain’t gonna happen.
> until an average person can pick up a DRM radio for a reasonable price at a retailer …
The only way to achieve this would have been for DRM to be both Free/Libre and dead simple to implement. If Tecsun et al could add the decoding logic to a DSP chip and add DRM to their (SSB-capable) radios for little-to-no cost, you could bet there would be plenty of DRM radios available.
There’s no technical reason digital broadcast receiver capabilities has to be costly to add to modern receivers; it’s entirely due to ossified business models. They should have done everything they could to build an audience, and based their business model on the broadcasters wanting to reach that new audience. Of course, they wanted to extract their pound of flesh from both, and so have neither.