This is a PCB that allows you to build a small very LoRa tranceiver for long distance sensor and tracking applications. The board is very easy to build with only a small number of components needed. The board is powered by the Seeeduino XIAO SAMD21 or XIAO RP2040 processor boards, which are tiny, powerful and low cost microcontrollers with plenty of memory that you can program with the Arduino IDE. The LoRa module can be a Hope RFM95, RFM96, RFM97 or RFM98.

Note this is the supply of the PCB only, you will need to supply other components, including your own XIAO and RFM9X modules, wires and solder.

The XIAO is fitted to the board with the pin headers that came with the XIAO and the RFM9x can be surface mounted or soldered in place with 2mm pin headers. There is very little other assembly to do, just solder some wires add pin headers for connections your done.

You can fit a 0.1" screw terminal for the battery and a reverse supply protection diode, D1, and a polyfuse, FS1, if needed. You can fit connectors for I2C devices, serial UART devices such a a GPS, an OLED display and a connector for an external SD card. The documentation repository has Arduino sketches for using the board as a very compact GPS tracker transmitter or receiver with display. Also there are examples for using a BME280 for remote temperature, pressure and humidity monitoring and data logging.

There are I2C pull up resistors that can be fitted for external I2C devices, but these are often not necessary. On one IO pin you can fit a resistor for driving an external LED or or use a pair of resistors for as a voltage divider and read external voltages.

You must check that you can program the Seeeduino XIAO board with the Arduino IDE before soldering it to this board. For details on how to install the Arduino IDE for the XIAO see the Seeeduino provided documentation.