Long Range Arduino Based Walkie Talkie using nRF24L01
Amazon.com: Gowoops SX1276 LoRa Radio Wireless 862-930MHz 915MHz UART Serial Module LoRaWAN Transmitter Receiver + 915Mhz 3dBi SMA Antenna, Compatible with Arduino STM32 51 Single Chip Microcomputer : Electronics
LoRaSerial Hookup Guide - SparkFun Learn
Make your own very crude Walkie-talkie with an Arduino - YouTube
Iron Man Walkie-Talkie (Two-Way Radio) for Texting w/ LoRa - Hackster.io
Amazon.com: SX1262 LoRa HAT for Raspberry Pi 915MHz Frequency Band Data Transmission up to 5km Support Auto Repeating to Transmit Longer Wake on Radio Wireless Config Carrier Sensing Communication Key : Electronics
Build Your Own Mini Walkie-Talkie with ElectronicTricks' SnapOnAir PCB - Hackster.io