The DMR Tech Net team has a monthly show on Zoom called DMR Tech Net TV on the third Tuesday of each month from 8pm-9pm ET
- We have Steve Miller KC1AWV and Ed Wilson N2XDD to discuss the M17 Network Project & the WPSD Pi-Star hotspot interface tonight, May 21st
- Click the following link: https://us02web.zoom.us/j/84447664395?pwd=djZMbFZaWVRkRDRudkRFeWc2WWV4UT09 to join the DMR Tech Net TV Zoom meeting tonight on Tuesday, May 21st, from 8pm-9pm ET.
- Or point your internet browser to www.zoom.us and select “Join a meeting” in the top right-hand side. Then input the following to join:
- Meeting ID: 844 4766 4395 and Passcode: 370040
- To join with only your phones’ audio, dial (312) 626-6799 and input the following:
- Meeting ID: 844 4766 4395 Passcode: 370040
- We’re working to schedule Corey Dean N3FE of BrandMeister USA to go over his network, how to get the most out of using it, and best practices. Stay tuned as we work on finding a time and date convenient for him.
- If you missed previous DMR Tech Net TV broadcasts, you can watch them on our YouTube channel:
https://www.youtube.com/channel/UCq4TAnA-_yE7kdcuaKzw8rQ - If you have a topic or issue you would like discussed, let us know.
You can always chat with the DMR Tech Net team on TGIF talk group 31268, the DMR Tech Net channel or Brandmeister talk group 31266, the Michigan Nets channel.
If you have a comment or a DMR topic idea for the DMR Tech Net or DMR Tech Net TV, please share it with any of us. Send an email to: steve@dmrtechnet.net, stan@dmrtechnet.net, tom@dmrtechnet.net, dana@dmrtechnet.net, brian@dmrtechnet.net, or brad@dmrtechnet.net.
If you want to subscribe to this newsletter, send an email to subscribe@dmrtechnet.net and we’ll get you added to the list.
Here are the Michigan DMR nets we know about. Please join in & participate on them.
Saturday:
- 7:00pm Arrow DMR Net on BrandMeister talk group 3126
- 7:30pm DMR Trivia Net on TGIF talk group 31268
Sunday:
- 6:30pm UP (Upper Peninsula) Net on BrandMeister talk group 31268
Monday:
- 7:30pm DMR Tech Net on BrandMeister talk group 3126
- 8:30pm Michigan One DMR Net on BrandMeister talk group 3126
The DMR Tech Net team is helping Dustin N8RMA with NCS duties on the Michigan One DMR net on Monday nights.
If you would like to help out with our schedule of Net Control Station operators, send an email to dana@dmrtechnet.net.
Here’s the upcoming list of substitute NCS’:
- May 27 Dana KCØMYP (Yes, it’s Memorial Day and we will have both the DMR Tech Net & Michigan One DMR Net running)
- June 3 Steve KC8WXM
- June 10 Dustin N8RMA
https://www.michiganonedmr.net/
- When will we see a M17 Network radio?
- What is the M17 Project?
- If you have a pi-star hotspot, are you running the WPSD software?
- Why is it better than the standard pi-star version?
- Join us Tuesday night, May 21st on Zoom from 8pm – 9pm ET on DMR Tech Net TV as we discuss these questions with Steve Miller KC1AWV and Ed Wilson N2XDD. They will go over the M17 Project Network and WPSD software and answer your questions.
Click the following link for the DMR Tech Net TV Zoom meeting on Tuesday from 8pm-9pm ET: https://us02web.zoom.us/j/84447664395?pwd=djZMbFZaWVRkRDRudkRFeWc2WWV4UT09
M17 is a new digital radio protocol in development as an alternative to those currently available. It is being developed by and for amateur radio operators. The protocol’s voice mode uses the free and open Codec 2 voice encoder, which means there are no patents, no royalties, and no licensing or legal barriers to scratch-building your own radio or modifying one you already own. Applications and projects with M17 support include:
- OpenRTX – free and open-source firmware for ham radios
- DroidStar – digital voice client for Android
- SDR++ – multiplatform, open-source software defined radio receiver
- SDRangel – multiplatform, open-source software defined radio receiver/transmitter
- OpenWebRX – web-based software defined radio receiver
- mrefd
- rpitx
M17 (amateur radio)
From Wikipedia, the free encyclopedia
RF spectrum of the M17 protocol
M17 is a digital radio modulation mode developed by Wojciech Kaczmarski (amateur radio call sign SP5WWP) et al. M17 is primarily designed for voice communications on the VHF amateur radio bands, and above. The project received a grant from the Amateur Radio Digital Communications in 2021 and 2022. The protocol has been integrated into several hardware and software projects. In 2021, Kaczmarski received the ARRL Technical Innovation Award for developing an open-source digital radio communication protocol, leading to further advancements in amateur radio.
Technical characteristics
Spectrogram of the M17 protocol transmission. Time is on vertical axis, advancing from bottom to top. There’s a 40-millisecond preamble visible at the beginning of the transmission.
M17 uses Frequency-Division Multiple Access (FDMA) technology in which different communication streams are separated by frequency and run concurrently. It utilizes 4,800 symbols per second, 4-level frequency-shift keying (4FSK) with a root Nyquist filter applied to the bitstream. Radio channels are 9 kHz wide, with channel spacing of 12.5 kHz. The gross data rate is 9,600 bits per second, with the actual data transfer at 3,200. The transmission, called stream, is divided into 40-millisecond long frames, each prepended with a 16-bit long synchronization word. A group of 6 frames form a superframe and is needed to decode the link information data. Protocol allows for low-speed data transfer (along with voice), e.g. GNSS position data. The mode has been successfully transmitted through EchoStar XXI and QO-100 geostationary satellites. The protocol’s specification is released under GNU General Public License.
Voice encoding
M17 uses Codec 2, a low bitrate voice codec developed by David Rowe VK5DGR et al. Codec 2 was designed to be used for amateur radio and other high compression voice applications. It is based on linear predictive coding with mixed-harmonic sinusoidal excitation. The protocol supports both 3200 (full-rate) and 1600 bits per second (half-rate) modes.
Error control
Three methods are used for error control: binary Golay code, punctured convolutional code and bit interleaving. Additionally, exclusive OR operation is performed between data bits and a predefined decorrelating pseudorandom stream before transmission. This ensures that there are as many symbol transitions in the baseband as possible.
Application functions
The M17 protocol was primarily designed for amateur radio use.
- Callsignencoding: 48-bit field holding up to 9 alphanumeric characters eliminates the need of a centralized user-ID database.
- Encryption:
- Bit scrambler encryption: a pseudorandom binary sequencecreated by combining an exclusive-or bitwise operation on the audio or data stream and a linear-feedback shift register using one of 3 feedback polynomials with 255, 65,535 and 16,777,215-bit repeat periods.
- AES encryption: 128-bit block encryption cipher operating in CTR modewith user-selectable 128, 192 or 256-bit key.
- Slow-speed side channel for short and repeated data transfers, e.g. GNSS position data or telemetry.
- Text messaging.
Hardware support
With a small hardware modification, TYT MD-380, MD-390 and MD-UV380 handheld transceivers can be flashed with a custom, free, open source firmware[12] to enable M17 support.
Bridging with other modes
Links between M17 and other digital voice modes and Internet linked networks exist, with several networks providing M17 access. Modes bridged include DMR, P25, System Fusion, D-STAR, NXDN, AllStarLink, EchoLink and IRLP.
M17 over IP
Access nodes and repeaters[19] can be linked using reflectors. Over 180 M17 reflectors exist worldwide (January 2024).
History
The project was started in 2019 by Wojciech Kaczmarski in Warsaw, Poland. A local amateur radio club he was a member of, was involved in digital voice communications. Kaczmarski, having experimented with TETRA and DMR, decided to create a completely non-proprietary protocol and named it after the club’s street address – Mokotowska 17. As every part of the protocol was intended to be open source, Codec 2 released under the GNU GPL 2 license, has been chosen as the speech encoder.
Applications and projects with M17 support
- OpenRTX – free and open-source firmware for ham radios
- WPSD – digital voice software suite for amateur radio personal hotspots and repeaters
- DroidStar – digital voice client for Android
- SDR++ – multiplatform, open-source software defined radio receiver
- SDRangel – multiplatform, open-source software defined radio receiver/transmitter
- OpenWebRX – web-based software defined radio receiver
- mrefd – M17 reflector
- rpitx – general radio frequency transmitter for Raspberry Pi[
- dsd-fme – digital speech decoder
- mvoice – voice client and graphical repeater application (Raspberry and Linux)
https://en.wikipedia.org/wiki/M17_(amateur_radio)
The M17 Project
M17 is a community of open source developers and radio enthusiasts. We’re building understandable systems in support of the hackers and experimenters’ history of ham radio.
M17 is developing new open source hardware, software, and a digital radio protocol for data and voice, made by and for amateur radio operators.
M17 is about unlocking the capabilities that amateur radio hardware should already have.
Here you will find people working on radio hardware designs that can be copied and built by anyone, software that anyone has the freedom to modify and share to suit their own needs, and other open systems that respect your freedom to tinker.
https://m17web-new.kc1awv.net/ Buy a T-Shirt!
OPEN SOURCE DIGITAL RADIO
Our Current Goal
M17 is developing open source hardware, software, and offers a complete digital radio protocol for data and voice, made by and for amateur radio operators.
Our protocol’s voice mode uses the free and open Codec 2 voice encoder. This means there are no patents, no royalties, and no licensing or legal barriers to scratch-building your own radio or modifying one you already own.
This freedom to build, understand, and innovate is core to amateur radio, but has been missing from the commercially available digital voice modes. This is part of why amateur radio digital voice modes have largely stagnated since the 1990s and we’re almost wholly dependent on commercial products that aren’t well designed for amateur radio users.
M17 is about unlocking the capabilities that amateur radio hardware should already have.
Here you will find people working on radio hardware designs that can be copied and built by anyone, software that anyone has the freedom to modify and share to suit their own needs, and other open systems that respect your freedom to tinker.
Read the specification Get Started
Active Projects
The M17 Protocol Spec
Some quick text about the protocol specification
Module17
A digital voice ‘smart-mic’ to turn your existing 9600 baud capable analog radio into an M17 capable transceiver
OpenHT
Open source SDR (I/Q) handheld transceiver, capable of all-mode operation
M17 RRU
Remote Radio Unit, an FM/DV repeater designed for use at the top of a radio tower
Contact Us on: Discord, Matrix, Twitter, Mastodon, GitHub, YouTube, Ref M17-M17, M17 News
The M17 Project’s main chat service
M17 has a Matrix Space as an alternative to Discord
M17 Project’s presence in the Fediverse
The M17 team can usually be found on Module C
IN SUPPORT OF THE M17 PROJECT
Grants
Amateur Radio Digital Communications (ARDC) is a private foundation that exists to support amateur radio and digital communication science and technology. ARDC makes grants that support amateur radio, funds scholarships and worthy educational programs, and financially supports technically innovative amateur radio and digital communications projects.
ARDC awarded the M17 Project $250,000 in April 2021 for RF design and development, including test equipment, prototypes, and developer kits. They will also be used to provide bounties for solutions to particularly hard problems, and for the administrative work that is less likely to get done on intrinsic motivation alone.
In September 2022, ARDC awarded the Project $228,900 for further development and activities, including hardware proliferation, improvement of internet linking, standardization process, repeater maintenance, and other EU-based operations.
INCREDIBLE DONATIONS OF
Equipment
Ettus Research™, an NI brand since 2010, is the world’s leading supplier of software-defined radio platforms, including the Universal Software Radio Peripheral (USRP™) family of products.
Learn more about Ettus Research at their website, https://www.ettus.com/about/
ZUM Radio‘s mission is to develop and manufacture the highest quality communications equipment for amateur radio enthusiasts. They specialize in producing hotspots and digital mode repeaters – such as their best-selling ZUMspot and MMDVM-Pi products. They are also co-founders of, and regular contributors to, the MMDVM project.
ZUM Radio’s ZUMspot hotspots and MMDVM-Pi repeater boards support the M17 Protocol.
Learn more about ZUM Radio, Inc and their products at https://zumradio.com
WE LOVE THESE FOLKS
Sponsors and Partners
Open Collective Foundation (OCF) is a fiscal sponsor dedicated to providing a simple, open, lightweight path for charitable Collectives and communities to operate through a 501(c)(3) charitable entity.
You can donate to the M17 Project through Open Collective here.
OCF is the fiscal sponsor of the M17 Project.
OpenRTX is a free and open source firmware for digital ham radios, top-down designed with modularity, flexibility and performance in mind.
OpenRTX supports the M17 Protocol with firmware that includes TX and RX capabilities for popular HTs, mobiles, and custom-built Amateur Radio hardware to help get Amateur Radio operators on the air with M17.
Mobilinkd – Highly mobile packet radio
Mobilinkd, LLC specializes in portable packet radio devices, such as the TNC3, and NucleoTNC. Mobilinkd’s TNCs are easy to use, and compatible with most HTs and mobile radios.
Mobilinkd supports the M17 Protocol on the TNC3 and NucleoTNC. Mobilinkd also supports the M17 Project with assistance developing the M17 Protocol, and with providing voice and packet mode applications for mobile devices.
DARC – Deutscher Amateur Radio Club e.V.
The Deutscher Amateur Radio Club e.V. (DARC) (in English, German Amateur Radio Club) is a national non-profit organization for amateur radio enthusiasts in Germany. It acts as our fiscal sponsor for Europe-based endeavors.
M17 Project Team
Wojciech SP5WWP, Founder and Lead Developer
Bare-metal software developer. Radio amateur since 2016. Open source and hardware movement enthusiast.
Steve KC1AWV, Systems Administration and Integrations, Web Developer
Senior Systems Administrator for a non-profit based in Boston, Massachusetts. Enjoys coding, tinkering, and playing with radios!
Ed N2XDD, Community Manager, Primary NCS
Old school analog radio enthusiast living in a digital radio world. Recently retired and rarely found without a large cup of coffee in hand. Radio Amateur since 1993.
Chip W0CHP, Hotspot & Client Software Development, Systems Administration
Retired IT executive & engineer of 28 years. Serial entrepreneur, unapologetic life-long gearhead, F/OSS developer and ham operator since the 80’s. Founder and principal developer of the WPSD project; the first digital voice hotspot & repeater software distribution to natively and fully support the M17 protocol. (WPSD is an official M17 project)
Mathis DB9MAT, Hardware Development, Module17
Research associate in mobile communications. Part time PhD student, full time tinkerer. Open hardware enthusiast
Morgan ON4MOD, Hardware and Software Development
Research Engineer in embedded systems and radio communications. Loves Open-Source as well as learning new things. Bakes waffles.
Rob WX9O, Software and Hardware Development
Fintech Software Engineer & Founder of Mobilinkd LLC. Enjoys digital signal processing, embedded systems, and electronic design. Still trying to master the FPGA.
Doug AD8DP, Software Development – DroidStar
Automotive powertrain electronics engineer. Open source hardware & software enthusiast, GNU/Linux advocate, and self proclaimed ‘Gadgeteer’. Radio amateur since 2013.
Tom N7TAE, Software Development, Protocol Networking
Retired Physical Chemist. Now a radio amateur and open source software guy interested in digital comms.
https://m17project.org/about/team
Hardware
M17 is currently experimenting with existing hardware, and developing new hardware for use with the M17 Protocol.
Module 17 is a smart-mic module that plugs into existing 9600 baud capable radios (such as the Kenwood V71 and D710, Motorola Waris (CDM/GM), and others)
digirig is ‘a tidy digital modes interface for ham radio’ that can be used to transmit and receive M17
- A detailed how-to by Rob K9OJ regarding the digirig and a Yaesu FTM-200 can be found at his site robrobinette.com
ADF7021 Module is an experimentation module for the prolific ADF7021 RF chip, commonly used for DV hotspots.
NucleoTNC developed by Mobilinkd as an open-source TNC platform that supports the M17 Protocol.
TNC4 also developed by Mobilinkd is a commercial TNC that supports the M17 Protocol.
OpenRTX is a free and open source firmware for digital ham radios (TYT MD3x0 and clones, Ailunce HD1, Module 17, and more) that supports the M17 Protocol.
https://m17project.org/get-started/hardware