D-STAR - WARC Web Site

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What is D-STAR?
Sourced from the FAMPARC Web Pages

Amateur Radio Digital has been around for many many years now, with modes such as DStar, DMR, Fusion and more.. A handful of WARC members use these Digital modes especially the well known DStar system. Our members use DStar to not only chat to local members but also interstate and around the world.
What is D-STAR?

D-STAR, which stands for ‘Digital Smart Technology for Amateur Radio’ is an open digital Amateur radio standard that offers users a number of ways to connect with other users globally via a worldwide network of digital amateur radio repeaters.

Just like other forms of Amateur radio, D-STAR has a broad appeal from those Amateurs wanting to communicate just for fun to those who would prefer to push their technical expertise.

The D-STAR protocol has rich, exciting opportunities for Amateur radio enthusiasts to experiment and build, utilising 21st century tools such as the web, networking, ethernet, TCP/IP and radio.

D-Star is innovative and is keeping radio Amateurs at the forefront of communication technology - Amateur radio has a great future and is moving forward right now with D-STAR digital technology.

Icom is reinvesting in D-Star technology and is now providing  4th generation D-Star radios with better codecs, better transmit and receive audio, better operational synergy and most of all, the same synergy and operational syntax is the same in all modern D-Star radios

Being connected to the gateway allows for connection to other users, locally, interstate, nationally and around the world via the internet.  You can connect to other users directly via callsign routing and by REF reflectors developed by Robin Cuttshaw AA4RC

You can do this with an Icom or Kenwood D-Star Radio via RF to Mt Dandenong VK3RWN or if you have one of the various types of modems, you can connect directly to Reflector 01C. The prominent worldwide reflector or Reflector 91C, based in Tasmania as a backup and for news services.

For other local and Repeaters further afield you can use your Smartphone using the App called Repeater Book.
D-STAR Features

  • Provides digital voice communication and data communication

D-STAR gives users the ability to connect via digital voice, it gives clear, crisp audio, on simplex.

D-Star facilitates slow speed data. This runs on the D-Star signal at 4800bps  This sends all the D-Star control data but also if your not using voice, allows slow data communication between ALL D-Star radios, when you hook them up to a PC using programs such as "D-Rats" You are able to send files, text messages and chat via keyboard, great for EM applications Slow Data can be used on all three bands... or modules C = 2m, B= 70cm and A-23cm.

  • Fast Data 1.2GHz 23cm)

In order to send and receive greater volumes of data and large files, D-STAR has the "DD Mode" or Digital Data Mode. The DD mode is only supported on the 1.2 GHz 23cm amateur band and is capable of sending a receiving data at a 128kbps rate.
No special or additional data modem is required to send and receive high-speed data on D-STAR on a 1.2GHz D-STAR radio all that is required is a standard Ethernet cable connection to your PC, via a router, using D-Rats, larger files like word, excel, JPG etc can be sent via fast data. It's suprising to see how fast a 1Mb file take to send ...only about 5 seconds.
Fast data was a hit with EM organisations after Cyclone Katrina in the US southern states, nearly all amateur radio EM units in the southern states are now using D-Star in their deployments  You'll need an Icom ID-1 or IC9700 to realise this operation.

  • Internet facilitated Global Connectivity

You can easily contact your friend directly  by putting in his/her callsign into your radio without knowing his or her current location or what D-STAR repeater they are on.

D-Star will log and remember where to route your call. You can also use reflectors. Reflectors are essentially a server that links repeaters , and shack based modem types such as DV Dongles, DVAPs, MMDVM's  Blue DV's Jumbo-Spots,  Dura-Spots, the list goes on, and high powered simplex repeaters to the same reflector via the Icom backbone.  

D-Star is NOT proprietory , any analog radio can operate as a node with a non proprietory D-Star modem, Kenwoods TH-D74 was wholly produced by Kenwood, and in truth one of the best handhelds ever

These days the cheapest and easiest modem to grab, if you not near a repeater is an MMDVM  (Multi-mode Digital Voice Modem). Many hams use them if they live right next door to the repeater as it gives them control, to go to different reflectors of their choice without upsetting current convo's on the repeater.  

MMDVM's have developed quickly with the introduction of Pi-Star software written primarily by Jonathon Naylor G4KLX.  MMDVM's have now gone to the next level as they allow your D-Star radio to connect to DCS and XLX reflectors. DCS reflectors work within the IRCDDB realm (VK3RMM) and XLX reflectors with these days are known as "Constellation" Reflectors

XLX Constellation reflectors have the abilty to transcode your DV signal into other protocols such as DMR, Fusion or P25. As an example  I can get on to the CQ-Wires UK Fusion Reflector by just putting  XLX922 Module E into my D-Star Radio and bingo, I come out at the other end in the UK on Fusion  A simple command  XLX922EL in the UR field on the radio. ( The L means link command) Thats it. !  Its not hard at all.

The evolution of D-Star has been massive, blinkers down and ignoring the noise from all the other agenda based groups. The first Australian international D-Star contact via VK3RWN and GB7IC Kent UK  repeaters on the 7th of November 2007.  Icom knew they had a game changer. Icom invited all manufacturers to produce D-Star radios, Kenwood came on board and others felt that their  totally proprietry Wires X system were superior, in their own honest opinions and at this stage DMR was still a land mobile protocol
Open System

As we said prior  D-Star is an OPEN system Voice is converted to a digital format using audio encoding software referred to as a CODEC.

The CODEC code is embedded on a microchip produced by DVI systems that ALL manufacturers may purchase. Part of the noise is that Icom produces it, This is incorrect. Most digital radio manufacturers purchase the AMBE chip which encodes and decodes the audio signals into and out  as Icom does  The only proprietory part of the D-Star system is the backbone. But do your research so is Fusion, DMR, P25 and most other minor protocols.
Hopefully after reading this you'll be able to switch off the noise

  • Good Quality Audio
The quality of the D-STAR voice signal is better than FM especially with the clubs new IC-9700 There is no degradation in the signal quality that is found with traditional analogue voice modes and no squelch tail at the end of every transmission.
Why is it better ? All digital protocols are written with an algorithm. The codec only understands voice, it does not understand extraeneos sounds like for examle wind
I dare you to have a conversation with somebody in your car with the microphone  in the wind at your window. It will be crystal clear at the other end

  • Efficient Data usage
Many data communications needs don’t require high-speeds, particularly for emergency communications. D-STAR combines voice and low-speed data into a single channel simultaneously.

  • D-Star goes further
D-Star and other Digital protocols will go 10% further than analog signals . Like any digital signal it will hold its signal to the 'Digital Cliff" Then dissapear, rather than a slow painful analog signal's degredation.

  • Spectrum Efficient
If you’ve tried to use a repeater channel on 2-meters or 430- 440 MHz in any city, you know how crowded the bands can be. The D-STAR voice and low-speed data signal offers a significant improvement in spectrum efficiency, requiring only a 6 kHz channel instead of the 20, 25, or even 30 kHz of analogue wide-band FM. D-STAR repeaters can be interleaved between existing channels or multiple repeaters deployed in the spectrum of only one analogue FM repeater.
How do I get involved with D-STAR?

There are a number of ways that you can get involved with D-STAR. The first major requirement is that in order to use the D-STAR system is that you must be a licensed operator. If you aren’t a licensed Radio Amateur, the best place to start is with your local club, where you will find information about the hobby and how to get into it.

Secondly you must register with D-Star.

D-STAR (Radio only)

You can use your handheld or mobile radio to connect with a local D-STAR enabled repeater and then use it to link to talk to people elsewhere in the world.  You must be registered to do this . All digital systems, you must be registered, its a licensing requirement with the ACMA

No D-Star Repeater?

Dongles and DVAPs
These modems are D-Star Old school, almost a decade old with little development, a dongle will plug into your PC and with the right FTDI drivers and Software "DV Tools" you'll be able to get on the gateway to any REF reflector and use your PC Mic and work the world, The  beauty of Dongles is that its just a little plug-in for your laptop and if you've got WI-FI they work well. An absolute must for a "Stealth Traveller"
DVAPS  plug into a USB port, red ones are VHF and Blue ones are UHF, same deal with the PC and software. They are old school but extremely reliable, easy to set up, all you need is a D-Star radio of any type and they work well

  • MMDVM  
An  MMDVM,  or Multimode Digital Voice modem is a vastly different device to the above devices. Its modern, cheap, well supported and the most popular offering. MMDVMs are far superior as they have moved with the times. Through Pi-Star Software you can program to do other protocols like DMR, Fusion, P25 but they do D-Star the best. That explanation for another day. They can link you to all the different REF, DCS and XLX reflectors. These days a neccessity.  They are cheap, all you need is a Raspberry Pi 3B+ and a hat, that plugs into the GPIO connector on the Pi a 16Gb SD card and that's it  Program the SD and you should be  on the air in minutes. I run four here , I set them on low power and they are all on 70cm with no noise or interaction They are by far fantastic.

If you want more infomation on MMDVM's contact  Glen VK4NGA, look up "Dura-Spot" they are of high quality and you get aussie support. Otherwise just search MMDVM on Ebay. If you want one for DMR make sure you get a "duplex" MMDVM .. It will operate  with two antennas, two time slots

  • Hotspots
Hotspots are very similar to the MMDVM although they are of different construction
The PCB does not have a radio and antenna A hotspot is different to an MMDVM because an MMDVM outputs roughly 10mW. A node radio for a hotspot can have an output of "anything" depending on the RF abilities of the node radio
They are a PCB that runs with a raspberry Pi The PCB has an assortment of cables to match your Node Transceiver Icom, Kenwood and Yeasu are normally DIN plugs that plug into a radio Motorola are like little PCB's that plug into the radio

If you want to build a hotspot, check out  www.bi7jta.com on the web, he sells kits for all types of amateur radio equipment .
Getting set up with D-STAR

The absolute first step is to get yourself registered on the D-STAR network. D-STAR Gateways enable users to connect from a local D-STAR repeater, equipped with a D-STAR Gateway, to any other Gateway equipped D-STAR repeater.

Once an Amateur is registered with a repeater gateway, it can connect to D-STAR users beyond the local repeaters. You do not have to be registered with a gateway to use a local repeater, only if you want to make use of the D-STAR network. You only have to register with one gateway as your registration information is propagated to all other gateways and reflectors in the D-STAR network.

The second step is to make sure you actually have a local repeater that supports D-STAR. Not all repeaters are ICOM, Like Micheal VK5ZEA / VK5LN at Port Lincoln SA, his D-Star repeater  is built with Motorola GM300's

If you are not near a D-Star repeater. It Doesn't matter Just register your callsign say and away you go,
Program your radio, program your MMDVM. You're on air.

To find out which D-STAR repeaters are in range and active in your area go to http://www.dstarinfo.com.
How does D-STAR work?

There are a number of ways you can communicate on the D-STAR network. These include using D-STAR enabled radios that are capable of 3 digital communication streams.

1. Digital voice
2. Control data
3. Data messaging

The occupied bandwidth of the digital signal is smaller than that needed in analogue transmissions and therefore more digital channels can be provided in a given bandwidth.

To enable the repeaters to communicate with each other over the internet the repeater is connected to a PC running a LINUX operating system and Gateway software. This software connects to other gateways and keeps the user lists up to date and connects the digital streams between repeaters.

All of the information is distributed within a network that is managed by a ‘Trust Server’. We are currently in the same net as America,UK and Canada

D-STAR repeaters can be operated in the same way as existing analogue repeaters except that they communicate using a digital transmission from the transmitting radio through to the receiving radio. Unlike other systems that have been developed that use the web for linking distant stations together, D-STAR treats all repeaters in exactly the same way. A local repeater is no different to a repeater 3000 miles away, you just have to route your call to the distant repeater. You can connect to a local repeater and a repeater across the internet and all participants will be treated as though they are on the same repeater.
Components of the D-STAR Network D-STAR repeater system

A D-STAR repeater system is typically composed of a repeater controller, 1.2GHz, 70cm or 2mtr digital voice repeater, digital data repeater and the Internet gateway PC.

The D-STAR repeater operates similar to an existing analogue repeater. That is a simple relay of transmit and receive communication within or across the 2m, 70cm or 23cm bands. When D-STAR repeaters are connected with the Internet gateway, the D-STAR system relays the received data over the Internet. Your message will get through virtually to anywhere in the D-STAR system.
D-STAR registry
As authorised users make their initial transmission to a D-STAR system, the call sign information attached to the digitised voice packets is recorded by the repeater controller. The controller then shares the information with other D-STAR systems through the D-STAR gateway registry.

The registry is maintained on gateway servers located around the world. When an authorised D-STAR user makes a call to a call sign not currently registered on that repeater system, the registry allows the repeater controller to route the call to the repeater on which the targeted user was last registered.
D-STAR reflector?
A reflector can be considered to be similar to a repeater, but with no RF capabilities. Reflectors are Internet connected servers, generally in data-centres, which receive a transmission from a connected gateway (via the Internet) and send it out to all other connected gateways for retransmission, via RF in the case of a repeater.

Reflectors are basically a conference bridge for D-STAR. They allow multiple D-STAR repeaters and MMDVM, Dongle and DVAP users, from around the world, to be joined together and whatever information is transmitted across one of the repeaters is repeated across all of the connected repeaters of that reflector or constellations that link refectors. Google  'XLX 500'
Conclusion D-STAR provides a whole host of opportunities for the Amateur radio enthusiast to challenge themselves with tools from the 21st. Century. As with all forms of radio, you can dip your toe in the water for just plain old communication or delve further if you are interested in setting up repeaters and send data as projects.

It might not be everyone’s cup of tea but this area of the hobby is growing with more and more repeaters and users being added all of the time... good luck in your digital journey!
There are many websites to find further information, ideas and support on this fascinating new part of Amateur Radio.

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