MMDVM - Mutli Mode Digital Voice Modem

  1. MMDVM Overview
  2. MMDVM - Multi Mode Digital Voice Modem
  3. Hardware and Firmware Support
  4. Building MMDVM on RPi from Scratch
  5. Pi-Star is the Web Interface to the MMDVM
  6. Zumspot MMDVM
  7. MMDVM NEWS from Ron, VE1CRA, Prince Edward Island, Canada
  8. Repeater Builder's STM32-DVM MMDVM
  10. Software Decoding Software

Related Pages:
  1. Pi-Star
  2. JumboSpot
  3. MMDVM_HS_Dual_Hat_Duplex Board
  4. Repeater-Builders-STM32-DVM


MMDVM Overview

This open source application consists of two peices of software and hardware,

This is often referened to as the "MMDVM" or "Mutli Mode Modem" and
this combined application has been adapted to several pieces of equipment.
They are essentially the same software application.

Examples of MMDVM implmentations


MMDVM - Multi Mode Digital Voice Modem

MMDVM is an open-source Multi-Mode Digital Voice Modem

The MMDVM Project is the brain-child of Jonathan G4KLX. The project is coordinated on the MMDVM Yahoo! Group. MMDVM is an open-source Multi-Mode Digital Voice Modem software application to allow for the development of homebrew hotspots. The source code for the MMDVM firmware supports

It runs on the Arduino Due, the ST-Micro STM32F407-DISCO and STM32F446-NUCLEO, as well as the Teensy 3.1/3.2/3.5/3.6. What these platforms have in common is the use of an ARM Cortex-M3 or M4 processor with a clock speed greater than 70 MHz, and access to at least one analogue to digital converter and one digital to analogue converter. A Cortex-M7 processor is prefered.

A must watch Video by Jonathan Naylor the author of MMDVM that was published 5th June 2017

A Video about the construction of the MMDVM Zumspot Libre Kit which is based upon the "Blue Pill" STM32 controller and assembled upon an adapter board.

The Brandmeister wifi has a homebrew MMDVM page that details tested radio transceivers:

The source code is available on github: - MMDVM source code on (github)

Detailed instruction from "F5UII – French Hamradio Station" on howto build the MMDVM hotspot on various ARM architectures. - Build your own homebrew MMDVM hotspot

And this site gives a list of the available MMDVM compatible shields: - MMDMV Shields

How To Make A MMDVM Digital Repeater by San Antonio Digital Radio:

Here is a comparison of various hotspots:


Hardware and Firmware Support

The MMDVM support site:

The MMDVM Firmware can be upgraded on the STM32 hat by using the Pi-Star flash utiltiy.
Firmware upgrade steps are: Source:


Building MMDVM on RPi from Scratch


Pi-Star is the Web Interface to the MMDVM

Management of the of the MMDVM is via a web interface called "Pi-Star".


Zumspot MMDVM

The Zumspot was an early hardware project of the MMDVM hotspot and most development appears to be done in and Canada and distributed by Bruce Given, VE2GZI. However, the Chinese clones are cheap (under $100 Australian) and have become very popular, dispite their lack of ongoing support. I guess they are almost a throw away item.

A popular Chinese clone of the Zumspot is called the Jumbospot and is available on many Ebay sites.
It has been often criticised as being unreliable but my unit has worked without fault.
See for details on the Jumbpspot: JumboSpot

This post appeared on the MMDVM blog site

I no longer sell anyEquipment/MMDVM Zumspot products this includes the Zumspot pi board, kits and the MMDVM-Pi
please check for more information
Please dont email me for any more information , As I will simply not reply
So long and thanks for all the fish!
Posted by VE2GZI and Company at 2:07 PM
That leaves us with the clone market.


MMDVM NEWS from Ron, VE1CRA, Prince Edward Island, Canada

Ron, VE1CRA's Canadian site has a great deal of history and technical information on the Zumspot and MMDVM in general.

Three links are particularly interesting: - Zumspot & MMDVM Demo page


Repeater Builder's STM32-DVM MMDVM

This is a STM32 based daughter board on a Raspberry Pi 3 Model B+.
It is supplied by Repeater Builders in the USA.
Details of the STM-32 MMDVM can be found here:
Repeater Builder's STM32-DVM MMDVM





Software Decoding Software


Configure a Pi-Star Hotspot for Multi-Networks (BM, DMR+ & TGIF)

Multi-Network Configuration:

Configure acpi-star hotspot for multi networks plus much more

Glenn Lyons VK4PK
Ver:gnl20190705 - pre published v0.9