One of the most significant challenges digital has in ham radio is the multiple modes across manufacturers. D-Star, DMR, C4FM, P25 are all on the amateur bands across the United States, but could these digital modes we all know and use come to an end? If a new startup project has anything to say about it, the answer is yes.
The history of M17
The project is known as M17 and started in early 2019 to replace our current suite of proprietary digital voices modes. Amateur radio operators in Europe noted that there is no genuinely open, free-to-use digital radio system. M17 was born with over 100 ham radio operators and hackers around the world working on the project.
“The goal here should be to kick the proprietary protocols off the airwaves, replace DMR, Fusion, D-Star, etc. To do that, it’s not just good enough to be open, it has to be legitimately competitive.”
– M17 Project
The manifesto is simple. M17 wishes to provide:
- Open-Source community
- Freely available and modifiable digital radio protocol
- Open hardware designs
Technical specs of M17 protocol
So how does it differ from things like DMR? M17 uses Frequency Division Multiple Access (FDMA) instead of Time Division Multiple Access (TDMA). FDMA, in the case of M17, allows for two 6.25kHz simultaneous links to be established on one 12.5kHz channel at 3200 bits per second. It’s using a Codec2 vocoder that M17’s developers say outperforms current proprietary vocoders currently on the market. Check out the full protocol specifications for M17.
Users are registered with the network using User IDs generated based on their callsigns. Base40 is used to encode the callsign into a 48-bit value. The user ID can be translated to a DMR Radio ID equivalent utilizing a lookup table.
When you look at the M17 hardware, you’ll find the TR-9 HT. The TR-9 can use FM voice or M17 digital pushing 3 watts of RF power via an ADF7021 chip, which is specifically designed for 4FSK modulation.

Which digital ham radio protocol is best?
Those that have talked to me know I’m not too fond of the D-Star protocol. I find the voice quality not up to par, and the registration process is an absolute nightmare.
I’ve been a Digital Mobile Radio (DMR) user for nearly seven years, and it has the same hurdles of not being user friendly. Then again, DMR was never intended for ham radio — so that’s no fault to DMR. It’s become wildly popular because of the cheap radios that have flooded the market from China. The affordable entry costs have floated DMR and the Brandmeister network to the top of the digital heap.
Then you have C4FM/YSF, which I find to be very enjoyable. It’s easy to use, and you don’t need to worry about a 100-setting codeplug to make it all work. If you can program an analog repeater, you can do C4FM/YSF.
Yaesu has been smart in selling their analog/digital repeaters cheap to spread the protocol, which has helped its popularity, but DMR is still more active across the board.
Is M17 good for ham radio?
Ham radio operators have been trying to solve the issue of multiple protocols for years, and M17 is yet another effort. Look no further than the Colorado Digital Multiprotocol Network that bridges different protocols together in a single spot. But is that the long-term answer?
I would love to see a protocol emerge that all radio manufactures would get behind. The issue of differing protocols exists in public safety too, this isn’t just an amateur radio problem. We need to build a superior protocol and lobby the manufacturers to adopt it. Having protocols that use proprietary elements doesn’t help anyone — well, maybe the manufacturers.
I think the M17 is a fantastic project, and if you’re skilled and interested I would encourage you to get involved in the effort. M17 is looking for people with the following skills:
- C programming (Raspberry Pi, STM32, PC)
- PCB routing (preferably KiCAD)
- Familiarity with 3D printing, CAD/CAM
- Soldering, prototyping
- Open mind β concept testing
Let’s make digital ham radio great…. for the first time!
Looking forward to the development of a non-proprietary digital protocol for amateur radio. I will say that in my opinion, C4FM is the better of the digital protocols but I donβt like that you are tied to Yaesu equipment.
You are renaming DMR, why? to get rid of Motorola?
What does that mean dmr in nor motorola exclusive, mototurbo is just open dmr standard with a bit of motorola touch on it
What is it about M17 that is “renaming DMR”? DMR is TDMA, M17 is FDMA. DMR is 4FSK, where they don’t specify what M17 modulation is.
M17 uses 4FSK along with error correction
Actually, DMR has become internationally popular under the name “Digital Mobile Radio”. It has become the defacto standard for commercial digital radios around the world. Of course Motorola established the technology and protocol, but it has become popular because it runs on multiple hardware platforms. So for our ham radio purposes, Digital Mobile Radio is the correct name to use.
YADP (yet another digital protocol) to complicate things further. great
“… now we have 16 competing standards” (c) xkcd
Why are you asking about renaming anything? We don’t want to rename DMR, we propose a new DV standard. That’s all.
Not going to “kill off DMR, DSTAR and YSF on ham bands” will just become another mode, like P-25. Some will use it, some will not.
BOTTOM LINE: if digital doesn’t sound better than existing analog, no sensible person will use it. So far, nothing has offered that quality.
What if anything can this do with respect to data transfer. Voice is dead. Does this have a DRATS like interface to pass data files, pdf, jpg, xls, csv, Real Data, email, chat, txt, ? Does it have maping, ICS form transfer all the things that are needed in Emergency traffic? If you want to talk, get an FM radio. Get over voice, its not what Office of Emergency officials want or need. Fast data is what OEMs want. If Ham radio is to stay relevant in todays and future Emergency Communication the Ham Radio must send data first, voice second with less bandwidth. FCC will be mandating 6.25 Max bandwidth shortly. Conversations about voice quality are moot, they all sound like !@#$ compaired to FM, they are Digital. Move forward not sideways. N2KTO Dave
I HAVE BEEN A HAM FOR SIXTY YEARS. WHILE I DO NOT OPERATE ANY MODES OTHER THAN CW, SSB, AND FM, I DON’T SEE THE SENSE IN ADDING A NEW NAME FOR AN EMISSION TYPE ALREADY WIDELY IN USE – SUCCESSFULLY I MIGHT ADD. MANY FRIENDS OPERATE GREAT COMMUNICATION WITH THE CURRENT MODE(S). WHY TRY TO FURTHER COMPLICATE THE HOBBY WITH WHAT APPEARS TO ME TO BE ANOTHER NAME FOR THE SAME PRODUCT? ’73 KF9F
It’s always great to see something new created by Hams. It sounds intriguing. I applaud the effort. However, I doubt if Kenwood, Icom and Yaesu, with the investment that they have in D-Star and C4FM will just drop these protocols and support M17 anytime soon. I think that it will become an alternative to the present digital Amateur Radio, but I don’t see it “killing off” anything.
Plus, there are many repeater systems that allow for interconnectivity between the different radios
Best wishes and best of luck. 73 K3ZE