ESP32 Codec2/OPUS DV Handheld Transceiver

Introduction

This project is amateur/ISM radio ESP32 based LoRa/FSK Codec2/OPUS DV handheld trasceiver, which is using 1W E22-400M30S (SX1268) radio module (UHF, 70cm band).

It is interoperable with https://github.com/sh123/codec2_talkie application.

It is based on https://github.com/sh123/esp32_loraprs modem, but uses additional peripherals:

• I2S speaker module MAX98357A + 4ohm 3w speaker (40mm diameter)
• I2S microphone INMP441
• PTT button
• Rotary encoder with push button
• Small OLED display SSD1306 128x32
• Battery voltage monitoring
• Powered from a single commonly avaialble 18650 battery
• Uses combined charge + 5v boost controller based on Hotchip HT4928S

Supports next features:

• Supports LoRa and FSK modulation with configurable modulation parameters from settings
• Supports Codec2 (low bit rate) and OPUS (medium/high bit rate) audio codecs, codec could be selected from settings
• Goes into ESP32 light sleep when no activity, so all power consumption is around 30-40mA when in RX, wakes up on new data from radio module or when user starts transmitting
• Settings menu on long encoder button click, allows to change frequency and other parameters
• Output power tunable from settings from ~1mW (for ISM toy usage) up to 1W (for amateur radio experiments)
• Experimental privacy option for ISM low power usage (check your country regulations if it is allowed by the ISM band plan before experimenting!)

Build instructions

• Modify include/config.h if needed
• Install platformio
• Build with platformio
• Upload with platformio

Picture