How to easily connect a NRF24L01+ transceiver to your Raspberry Pi Pico - Coffeebreakpoint
2-Channel RS232 Module for Raspberry Pi Pico, SP3232EEN Transceiver, UART To RS232 - Melopero Electronics
How to Build a Raspberry Pi FM Radio Transmitter
Amazon.com: RS485 CAN HAT for Raspberry Pi 4B/3B+/3B/2B/B+/A+/Zero/Zero W/WH,Allow Long-Distance Communication via RS485/CAN Function Onboard CAN Controller MCP2515 via SPI Interface Transceiver SN65HVD230 : Electronics
Setup Raspberry Pi for Ham-Radio
2-Channel RS232 Module for Raspberry Pi Pico, SP3232EEN Transceiver, UART To RS232 - Melopero Electronics
Waveshare 2-Channel RS485 Module for Raspberry Pi Pico Incorporates RS485 Transceiver SP3485 Using UART Bus : Amazon.ca: Electronics