This board must cooperate Raspberry Pi PI3, orange cake, a variety of school development board do use. This board was used in GM300 GM3188 3688 950I 338 Vitex DR-1X, other types of repeaters and car stations should be studied independently. MMDVM ma to be a multimode open source digital voice modem that uses the power of an ARM processor and a simple analog interface card. Multi-Mode Digital Voice Modem is a combined development of do modem hardware and software to support all amateur digital voice modes. Initially, it will support D-Star and DMR, and later System Fusion and P.25, as well as the built-in FM repeater. MMDVM is designed for Arduino Due, Teensy 3.1/3.2 and mbed platforms, the only requirement for the hardware is support for ARM Cortex-M3, M4 or M7 core and do raw interrupts and ADC ports according to and digital signaling ports. Specification: Size: about 6.6*5.7*2cm/2.6*2.24*0, 79 inch Green color Material: PCB List of packages: 1 * relay board for Raspberry Pi 1 * Moto cable 2 * Adapter 1 * User Manual