There has been quite a lot of discussion regarding the relatively new (to the Amateur Radio Community) Digital and Internet linked communications technology. Systems such as D-STAR, DMR, Fusion and NXDN and P25 which use Internet Linked reflectors and VoIP platforms such as Zello, TeamSpeak and EchoLink which also utilise Internet as the carrier for communications. Many people accross the Globe use these systems in one form or another on a regular basis and derive great pleasure and satisfaction from it. These systems have their detractors though.
Let’s look at each sector of Internet Linked Voice Comms, starting with those modes generally accessible with a dongle such as the DVMega, MMDVM or Openspot. These systems usually consist of a Modem which takes the RF signal from a suitably equipped digital radio and converts it into a PC or Raspberry Pi for redistribution via a server. This communication is then decoded by other users in reverse order and received by their digitally equipped radios. The hotspot will typically run at a few milliwatts and a range from the transceiver typically around 30 or 40 metres is achievable. With the Internet link Global communications can be effected, thereby negating the need for complex antenna arrays, making this mode of comms ideal for those not in a position to erect towers or string wires over great lengths, such as people who live in flats or apartments and those more elderly operators who find themselves living in sheltered accommodation or nursing homes.
RoIP (Radio Over IP) systems such as AllStar and EchoLink work in a similar way to digital hotspots. A node, consisting of a radio, connected to a computer running the appropriate software picks up an analogue RF signal and distributes it in much the same manner, the received signal being relayed via the operators node to their analogue radio.
This brings us to Network Radio systems such as Zello and TeamSpeak. These are programs for PC or apps for a mobile phone or other VoIP device, which utilise the mobile or fixed internet and servers to distribute the comms. A typical Network Radio would run the Android operating system, Zello being the platform used to distribute the communication. Although not exclusively reserved for mobile devices, a computer or tablet can also be used.
Is it Real Radio?
Yes and no. Yes, in the sense of a WiFi router or mobile phone sends data via RF, either to a cell tower or on 2.4 or 5 GHz. Yes in that some form of PTT is used to speak. No, in the conventional interpretation of “radio”. Amateur Radio is mostly considered to be RF point to point communications, but that description is based upon old conventions.
Let’s consider the commercial application of VoIP. Many businesses use VoIP for their communications, mainly because a costly licence can be avoided due to the fact that they use mobile data on frequencies covered by the providers licence. Also a conventional mobile phone can be used, negating the necessity for expensive radio equipment (although dedicated cellular PTT devices are available). In the UK the Police Service use TETRA, essentially a VoIP system which uses a mobile data connection to provide essential communications. This system is due to be replaced by ENS, which works on similar principles, one major difference being an enhanced data service to provide almost constant coverage which is important for such vital communications.
What happens if the Mobile Data service is switched off? For security reasons the Government might require the mobile phone service to be inaccessible - for instance, in the case of a serious Terrorist threat or a natural disaster disables the service. Essentially there would be no alternative but to use point to point RF comms - that’s why Network Radio will NEVER be a total replacement for conventional RF. My standpoint on Network Radio and other Internet Linked communications is that it is supplemental to conventional radio. It’s not a replacement, merely another aspect of the communication hobby which complements the established systems that we have. In this case it’s no threat to what we already have, in fact if use of Network Radio encourages people to study for and attain an Amateur Licence (and there is evidence of this) then it can only be a good thing for the hobby in the long run.
The disappointing thing for me is that some within the Amateur community are decrying Network Radio and representing it as the Devils Work. For a hobby that has innovated from day one with the developmental history of radio and all the changes and advances over the 100 plus years of its existence, I find it dismaying that some people are still stuck in the mid 20th Century. Is Netflix real TV? Are MP3 tracks real recordings? Tuberculosis was around until the 1950’s, that didn’t make it a good thing. As technology advances we either go with it or let it pass us by. In Victorian England, would anyone ever have thought that International communications could take place with devices that fit in the palm of a hand? When railways first became commonplace the detractors said that travelling at high speed would kill you. My point is that instead of dismissing something, take the time to try to understand it instead of writing to RadCom and pulling the whole thing down, due in no small part to the stubborn ignorance and refusal to accept that progress is made, not only in communications but in all walks of life - and especially in medicine, something that many of the more senior detractors should be happy to embrace.
I will still be out and about with my portable HF gear, I will also still call on simplex frequencies and repeaters on V/UHF. I will still build aerials and other equipment and at the same time I will have my DMR hotspot and my Network Radio to supplement all of the above. I will always be a Radio Amateur and nothing will ever change that for me.
73 de 2E0ENN
Whilst not abandoning my interest in Hotspots and Digital Communications, I have recently been using my Network Radio equipment more just of late. I have used Zello for a few years but not to any great extent. I recently became aware of Network Radios Channels on Zello and decided to give it a try. To say that I’m impressed by it would be an understatement. Six channels, open to both Licenced and Non-Licenced people, there is activity all day long. There are some very knowledgeable people who participate, not only in th Amateur Radio field but also SWL’s and Android gurus. The conversations are informed, interesting and conducted in a very civilised manner. The Moderators are fair and attentive and the whole experience is very good. In light of this new found positivity, I have purchased two more Network Radios recently. 
In my attempts to set up the ultimate in a digital and internet linked station, I have been flexing my Debit Card recently. The first acquisition was a second hand dual band DVMega. This was obtained at a very reasonable price but the firmware was quite out of date which meant that it couldn’t be used with MMDVM Host software under Pi-Star. Instead of using MMDVM I selected DSTAR Repeater as the host and used it for a while for DSTAR only. I got to thinking that the firmware just had to be updated but I was daunted by having to solder a wire jumper to the delicate Pi Hat. In a rare moment of bravery I took the plunge and broke out the soldering station and magnified “helping hand” project stand. Taking the attitude of “nothing ventured, nothing gained” I proceeded to solder the jumper wire in place. This went with surprisingly little drama. I re-installed the Pi Hat to the Raspberry Pi and rebuilt the case. Following excellent directions from the Pi-Star Users Group, I set about the procedure of updating the firmware. The first attempt was not a success - I had missed a line in the code, but on correcting the error and ensuring the firmware version was correct it flashed successfully. So I now have a bargain DVMega, with the firmware update jumper installed, working with Pi-Star, just as it should. 
I keep on doing it. I can’t help it. I can’t resist a bargain when it comes to radio equipment. As if the recent purchases of DMR radios wasn’t enough, I’ve bought another two radios this month. Both are DSTAR radios, an ID-880 mobile and it’s handheld counterpart the IC-80. Both were very reasonable used bargains. This brings the number of DSTAR radios to four. 
It’s been a while since my last blog but things are a little different here at the home QTH. My station is now almost exclusively Internet linked, with the exception of a couple of local repeaters, mobile on V/UHF and portable ops on HF.
I now have access, via Hotspots, to both Phoenix and Brandmeister reflectors. I have two Hytera MD785 mobile radios, one VHF and the other UHF. The UHF radio is used for Phoenix, with a DV4 Mini and the VHF radio is used with a dual band DVMega RPi, using Pi-Star software. I still use the venerable TYT MD380’s, both VHF and UHF, for the same purpose. I also use a Radioddity GD77 dual band handheld for both. For portable/mobile use I have the DVMega/Bluestack, running BlueDV for Android, with the very useful Hytera PD365 radio.
