Here the new MMDVM projects I, BG3MDO, am working on, which are based on
G4KLX, VE2GZI, KI6ZUM, CA6JAC, F5UII, SQ6POG’s work,
and also some great ideas from BD7KLE, BD7MXN, BH7NJF, and Sonic.
What it is, MMDVM?
The Multi-Mode Digital Voice Modem (MMDVM) is a combined hardware and software development of a modem to handle all amateur digital voice modes. Initially it will support D-Star and DMR, with System Fusion and P.25 coming later, as well as a built-in repeater controller. The MMDMV board is used to convert an analogue radio to a digital one, MMDVM hotspot is a board comes with RF, and used as an Internet radio gateway.
The hardware will typically be ARM based, with initial developments being aimed at the Arduino Due and Teensy 3.1, and the STM32 range is also supported.
BG3MDO MMDVM designs:
1. MDO MMDVM board is for Raspberry Pi or any USB enabled embedded Linux development boards, for converting an analogue repeater as a multimode digital repeater.
The board uses STM32F407 as the main controller, along with RTC, temperature sensing, relay, USB and online firmware update functions as the extras compared to the standard MMDVM.
2. MDO MMDVM Hotspot board is for Raspberry Pi or any USB enabled embedded Linux development boards, this board is a digital RF hotspot, used as an internet digital voice gateway, for digital handhelds or mobiles. It uses STM32F103 as the controller, and ADF7021 as the RF (VHF or UHF supported). Extra bits are the USB and online firmware update functions. For UHF board, it uses an PCB mounted ceramic antenna.