AmateurRadio.com

David Rowe has released an early version of his low bit rate open source digital voice codec. Whilst this is certainly a significant achievement, I can’t get very excited about it for two reasons. First, it is incompatible with the AMBE codec used by Icom in D-Star, so it is never going to be able to work with existing D-Star equipment and it is not all that likely that it will be incorporated in future versions. And second, I still don’t see what benefits digital voice offers us as radio hams in the real world.

Digital audio gives you clear “fully quieting” audio up until the signal starts to be lost, when it quickly breaks up and you get nothing. Analogue audio experiences a gradual degradation as the signal gets weaker. Those who have used the two report that an analogue signal is usably copyable about 15 – 20% further out than a digital signal. I can understand that for some professional services nothing but clear copy will do. But we are amateurs who are supposed to be good at digging weak signals out of the noise. Is this really “progress”, in the context of what ham radio is used for?

The other reason for my antipathy to digital voice is that I question whether we need another voice mode at a time when VHF analogue voice operation itself seems to be in decline. Surely it would be better to be making more use of existing technologies like Echolink to create more activity for users of existing equipment than to introduce new digital modes that will have an even smaller number of users. I’ve seen D-Star radios up for sale because the original purchaser found there was hardly anyone to talk to, and D-Star has now been around for several years. I don’t see the availability of an open source digital voice codec changing that situation somehow.

Practical Wireless editor Rob Mannion G3XFD has been writing to radio clubs urging members to support a campaign to save analogue radio. However, the radio he wants to save is not ham radio but broadcast FM radio, which has been threatened with closure in the UK forcing users to switch over to the “new” Digital Audio Broadcast (DAB) system.

The much vaunted DAB was supposed to re-invigorate the UK’s radio industry, provide a raft of new and interesting IP based services to audiences, permit the launch of new national, regional and local radio stations and generate new marketing revenue for radio stations. However, DAB is almost dead on its feet, as users have been reluctant to buy expensive new radios which in many cases offer poorer reception and fewer stations than they can get on FM. If this reminds you of something more amateur radio related you can probably guess where I am going with this.

D-Star was supposed to re-invigorate VHF radio usage, deliver a raft of new, interesting IP based services like text messaging, DPRS and file transfer to users, permit international, national, regional and local contacts and generate new revenue for Icom. However it is struggling to gain acceptance as people have been reluctant to buy expensive new radios that will provide access to fewer repeaters and fewer local contacts than they can get on FM and have been underwhelmed by the new features offered. Nevertheless the creeping D-Starization of the VHF and UHF bands continues, with the regulatory authorities now apparently refusing to allow new analogue repeater proposals whilst fast tracking D-Star applications through the system.

It does not seem to me to be beyond the bounds of possibility for the powers that be to decide at some point that there will be a ham radio digital switchover, that all analogue repeaters should be switched off and sections of the bands previously authorized for analogue FM use will be allocated to digital.

Perhaps we amateurs need our own campaign to Save Analogue Radio before it is too late. If you oppose the D-Starization of the amateur VHF and UHF bands, feel free to use the “No D-Star” logo on your website, your forum avatar and anywhere else that people might see it.

Steve, GW7AAV, spotted a news item on the NZART web page which states that the authorities in New Zealand have become concerned about IRLP, D-Star, Echolink, APRS and similar modes as they do not appear to fit within the New Zealand license conditions. Their concerns include the use of unattended transmitters and unlicensed digipeaters for APRS and amateurs based overseas operating a NZ amateur station via the internet.

It’s easy to forget that other countries don’t have such liberal licensing conditions as we do in the UK, although I would point out that operating an Echolink, D-Star, IRLP or packet radio (including APRS) node is not within the standard license conditions here either – you are supposed to apply for special permission. I know there are many who feel that is a good thing, and even that internet linking is not amateur radio and should not be allowed anywhere in the world, at all, but my opinion is that prohibiting it devalues amateur radio.

This policy is probably one of the main reasons why the APRS RF network is broken for messaging as many people (myself included) who are unwilling or unable to comply with the requirements for obtaining permission avoid the problem by operating receive-only gateways. Consequently we have the situation where smartphone-based APRS using mobile internet connections are more useful than APRS over radio.

I certainly believe that the point of our hobby is to use radio wherever possible, but where the internet makes possible something that could not practically be achieved using RF alone I think that we should be permitted to use it.

The QRZ.com thread resulting from the news about the French petition to have D-Star made legal has not degenerated into the usual flame war. This afternoon it produced this interesting post by Gavin, G0LGB whe makes some observations that are quite jaw-dropping.

Gavin claims that “Repeater groups are being persuaded by financial incentives, free or drastically reduced equipment, fast-track applications via RSGB/Ofcom, to convert their under used repeaters to D-Star.” The logic of how converting an under used repeater to use a little-used digital mode will increase traffic escapes me. More likely it has to do with starting to establish a network by the back door in the hope of encouraging more users, after which the busy repeaters will come under pressure to change too. We are having D-Star forced upon us whether we want it or not!

The other worrying claim Gavin makes is that the repeater keeper has the ability to ban users, not just from the repeater but from the D-Star network as a whole. This would be fine if it was simply used to ban miscreants – though why someone would pay £500 for a radio just to swear or play music is also a mystery – but apparently people have been banned just for voicing opinions unpopular with the repeater owners (somewhat reminiscent of my own experience with the ROS digital mode!) This is possible because the system is digital – all packets of audio or data originating from you are stamped with your call so the network knows who you are and where you are (or at least which repeater you are in range of.)

I think that, regardless of the merits or otherwise of using digital voice on the VHF bands, D-Star is not the way to go. It vests too much power in the hands of one manufacturer, Icom, and in individual repeater owners. It’s just unacceptable to have a situation that could result in you being barred from your hobby just because a repeater owner disagrees with your views. I suspect that the people who find APRS too much like Big Brother won’t like this either.

Steve, GW7AAV, was quick off the mark to post about the announcement yesterday on the website of DR@F, the French association of amateur digital mode operators, that D-Star has been ruled illegal in France. The reasons for the ruling, if I understand correctly, are that D-Star permits a radio to be connected to the internet (which is apparently illegal in France) and that it breaches rules prohibiting encrypted communications on grounds of national security because parts of the patented proprietary AMBE codec are undisclosed.

The group is appealing for all European amateurs to sign a petition to the European Parliament against the ban. No doubt this will have as much of an effect as the two petitions to the British Parliament to get interference-causing internet-over-mains-wiring devices banned. Issues like this illustrate what a hopeless idea the European Union really is as it attempts to harmonize things between member states while countries (especially France, which started the EU but implemented only the directives that suited it) stick tenaciously to their own different rules and regulations when they want to.

I’m not sure if it is true that French amateurs are not permitted to connect radios to the internet, as if it were, Echolink nodes and APRS gateways would also not be permitted, and a quick check of some relevant websites show several of each with F callsigns currently operating. As for the argument that transmissions are encrypted, whilst the closed and proprietary nature of the codec does prevent someone from designing their own decoder, the chips (and indeed D-Star radios) are readily obtainable allowing anyone who wishes to do so to monitor communications.

I am not, as regular readers know, a fan of D-Star, but this looks to me a bit like the result someone who is also anti D-Star trying to abuse their position to get it made illegal in France. I hope our French comrades are successful in getting this ban lifted.

Kudos to Lynn KJ4ERJ, developer of the brilliant APRS client APRSISCE. Yesterday he read my comment that the program doesn’t support transmit through the soundcard based AGWPE software yet, and today it does! So now my APRS beacons are braaping out over the Cumbrian airwaves.

I have noticed a bit more APRS activity round here in the last few weeks. Today I noticed another new station mobiling around the north-east of the county – G7NZR. The info for this station showed that he was actually using DPRS, the digital version of APRS, and was being gatewayed through MB6CA. This is a D-Star simplex node set up by G7NZR. Its coverage map shows that MB6CA can’t be heard in Cockermouth or Workington, so for the time being at least West Cumbria is still a D-Star free zone.

When I looked at the MB6CA coverage map I was reminded of a map I saw some years ago showing the spread of grey squirrels across the county. Overseas readers may not know that the grey squirrel is an illegal immigrant – from the US, no less – and it has been gradually wiping out our indigenous red squirrels, so that there are now only a few pockets of them left.

Will D-Star be the grey squirrel to analogue FM’s red, gradually increasing its territory as more and more people are persuaded to make the switch, until Icom ends up with a virtual monopoly over the VHF and UHF bands?

In a comment to an old posting about D-Star in G4VXE’s blog, Lee N2LEE accuses me of being closed to new ideas. Does it matter that the AMBE codec is patented if it is the best one for the job, he asks? And how can you compare Echolink/IRLP to D-Star when D-Star is an digital end to end system with routing, linking and networking built in to the system so you can just enter someone’s callsign and the network will find them automatically?

To me, ham radio is not and never has been about reliable point to point communication. Communication is just the end-product of a process of experimentation and construction, or a pastime (think contests, DXing) where the unreliability and unpredictability of it is what makes it a challenge.

D-Star’s use of a proprietary codec closes that aspect of the system to experimentation. It doesn’t even permit interested amateurs to look at the code and see how it works. This is contrary to the spirit of amateur radio and the openness that has facilitated most developments to date by letting one idea lead to another. But to be honest I’m not all that bothered about the issue because codec technology, whether proprietary or not, is a closed book to most. I am more concerned about the possibility that digital voice modes might one day make analogue modes obsolete so that building a simple phone transmitter using SSB, FM or AM becomes a pointless activity. Ham radio does not have to slavishly adopt new technology, especially if that technology forces more of us to become appliance operators by making simple rigs that anyone can build obsolete.

As for digital end to end routing, why do we need it? We already have a system that can do that. It is called the mobile phone network. I didn’t get into ham radio in order to be able to do something ordinary people can already do. I want to be able to do things that they can’t. The unpredictability of propagation and the uncertainty of who you might work on a given band at any time are what makes a ham radio contact more interesting and more of an accomplishment than making a phone call. D-Star may be very clever technology but what it delivers is not what ham radio is about.

If the time ever comes when I think to myself “why am I struggling to make this contact on 20m SSB or whatever when I could simply type the guy’s call into my D-Star radio and have a comfortable chat” then that is the day I will give up the hobby for good. And I make no excuses for resisting the adoption of technologies that will bring that day closer.