# project — Open Hardware Directory

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**2 project listed.**

## Armachat LoRa Doomsday Communicator Build

Build guide for the original Armachat pocket LoRa communicator by Bobricius, featuring a QWERTY keyboard, TFT display, RFM95 radio module, and 18650 battery for off-grid messaging up to 4km range.

[Details](https://openhardware.directory/projects/armachat-lora-doomsday-communicator-build) | [Markdown](https://openhardware.directory/projects/armachat-lora-doomsday-communicator-build/md)

## Zephyr RTOS — Scalable Real-Time Operating System for IoT

Open-source RTOS under the Linux Foundation supporting 500+ boards across ARM, RISC-V, x86, and Xtensa architectures. Features multi-threading, BLE 5.0 mesh, native networking stack, and power management for resource-constrained IoT devices.

[Details](https://openhardware.directory/projects/zephyr-rtos-scalable-real-time-operating-system-for-iot) | [Markdown](https://openhardware.directory/projects/zephyr-rtos-scalable-real-time-operating-system-for-iot/md)