Repeater Systems: ATV | Digital Voice | EchoLink & IRLP | Repeater Rules | WX
Digital Voice: DV Modes | D-Star | DMR | C4FM
Comparison of DV Modes available on W6CX-DV
Thinking of getting into Digital Voice but can’t decide which DV mode to go for? They are all good, but here is some info to help you decide.
D-STAR
D-STAR was built for amateur radio, so the identifier is your callsign. For that reason, your callsign always travels along with each transmission and you actually don’t have to id verbally (though you should, to retain the habit). There is a moderate learning curve, but simpler than DMR, particularly when programming a new radio. Radios are really good, but quite a bit more expensive than DMR radios. Most are made by ICOM , but Kenwood has a really nice HT.
D-STAR as designed by ICOM supports only connections using Callsign Routing. It sounds neat – the network remembers where you were last heard (a repeater or a hotspot), and your friends can route their transmissions there using your callsign. The problem is many, many D-STAR users world-wide have not really learned how to respond to callsign-routed calls, so it is much less useful than you’d think.
That is why REF reflectors were invented. Your repeater or hotspot can be linked to a reflector and can hear and talk to all the others on linked-in repeaters or hotspots. There are now 4 different types of reflector protocols (DPlus for REF reflectors, DExtra for XRF, DCS and XLX). Hotspots can access all of them, and some repeaters can too (including W6CX-DX), but many repeaters only access the most popular type, those named REFxxxxx.
Bottom line – D-STAR is first class and versatile. The networks offer a huge variety of places to connect and talk.
DMR
DMR was developed for commercial land-mobile – police & fire, corporate mobile communications, etc. The identifier is a 7-digit DMR id which any ham license-holder can request and put into their radios, so this is not a big deal, though in the US you do need to id every 10 minutes. The two really important features of DMR are:
• DMR radios are made by many manufacturers which compete on price, so competition means you can get a good DMR radio for much, much less than a D-STAR or Fusion radio.
• DMR networks connect to TalkGroups. These end up being like reflectors, except the user of the radio decides which talk group to transmit on (as opposed to having the repeater or hotspot be linked to a reflector). The difference leads to a lot of flexibility, but also some complexity. The programming info for DMR radios is saved in a file on your computer and is called a codeplug (Motorola term).
DMR’s complexity goes back to it having been developed for a commercial/government market where the end-users were not asked to do anything technical – police officers should not have to become technical experts. So Motorola designed the radios and programming software to be done by professionals who could configure the radios to the organizations’ needs, then install them. These pros are trained and have become experienced in all things DMR. It stands to reason programming a DMR radio is not all that simple. That is not to say hams can’t master it. My recommendation is to get a working code-plug and use that as your starting point. Just realize it will take more time to get up and running than D-STAR or Fusion.
Bottom line – DMR radios are less expensive than other DV mode radios. And there are many varieties of talkgroups that you can choose to talk to. It is an excellent DV mode, as long as the extra setup-time is acceptable to you.
Fusion
Yaesu’s DV mode is called Fusion and is architecturally different from both D-STAR and DMR. They have their own network (Wires-X) and each meeting place is called a room. But rather than asking people to store info about the network and available rooms in each user’s radio, Fusion expects the network to store that info. So you basically have almost no DV-settings to worry about. Like analog FM, you just need to have a memory that gets you to your target repeater or hotspot, and from then on, you can search for rooms by having the radio ask the network to do the search. That means setup and learning curve when getting a new radio are very quick and easy. This is a big deal and a big advantage.
In my experience, compared to both D-STAR and DMR, there are fewer possible places to make connections, but there are still a lot and many are interesting.
Yaesu radios are relatively expensive, especially compared to DMR radios, but they are well-designed and well-built. So the overall experience is good.
All three DV modes have good, intelligible audio. Yaesu Fusion supports both narrow and wide band. Of course, wide is better audio quality, but even narrow is very slightly better (in some hams’ opinions) than the other 2 modes. Still, the difference is slight and all DV modes are excellent and intelligible.
Wrapping Up
We purposely did not cover bridges and transcoding. It is possible to use a radio for a given DV mode and connect it to a network bridge to another mode’s room, talkgroup or reflector (for example, use a Fusion to DMR room to bridge those two modes). Hotspots can now do a lot of that too. That is all useful for those who want just one DV-mode radio. So you should be aware of this capability, but it is recommended to just pick your mode and radio-type first, and learn about bridges later on.
No matter which mode you go with, you will have fun. Many people start out with a DV radio and access repeaters to get started. Most repeaters make it easy for users to connect the repeater to other network places when the repeater is not otherwise busy, but at some point, some get even more enthusiastic and get themselves a hotspot so they have full control over linking/connecting, without bothering others. And hotspots these days support most or all the DV modes.
For example, some hams may start with D-STAR using their nearby repeater. Then the following year they get a hotspot and use it just for D-STAR. Then they break down and buy a DMR radio and configure their hotspot for both DV modes. And some then get a Fusion radio, etc. But, of course, many others start with DMR or with Fusion. It comes down to personal choice.
Lessons Learned
Thank you Jim Moen K6JM and others for your work rebuilding W6CX and speaking about it at the June, 2021 meeting. Thank you Jim and Trevor Hall WA6JAU for repairing the repeater antenna after a storm in Feb, 2023.