Introduction

Imagine turning your Android phone into a fully functional Amateur Radio HF/VHF/UHF APRS-enabled digital voice (DV) transceiver. With Codec2 Talkie, this is now a reality. This innovative app enables Codec2 and OPUS voice communication over KISS, APRS UI frames, and FreeDV modes, transforming your phone into a powerful digital communication tool for amateur radio operators.

About Codec2 Talkie

codec2_talkie is an advanced Android application that supports digital voice communication using the open-source Codec2 and OPUS codecs. It facilitates seamless integration with radio modems, allowing for effective voice and data transmission over amateur radio bands. Whether you’re using LoRa, AFSK, or FreeDV, this app is designed to work with a variety of modems and transceivers, making it an ideal solution for ham radio enthusiasts.

Key Features

Voice Communication

• Send and receive Codec2 voice over FreeDV modes.
• Transmit and receive Codec2/OPUS voice over KISS.
• Encapsulate Codec2/OPUS voice into APRS UI frames for transmission.

Data Communication

• Support for APRS over various modulation schemes:
  • FSK 300 (HF, TX only)
  • AFSK1200 (VHF)
  • FreeDV OFDM (HF)
  • APRS-IS (Internet)
• Send and receive APRS position reports and messages.
• Maintain an APRS log with raw data.
• View APRS station information on a map.
• Act as an APRS digipeater and an APRS-IS RX/TX iGate.
• Enable APRS-IS internet tracking for APRS data over the Internet.
• Send and receive LoRa-APRS text packets over KISS.

Hardware and Software Integration

• Works with Bluetooth/BLE/USB/TCPIP KISS hardware modems, including LoRa, FSK, AFSK, etc.
• Supports KISS software modems like Direwolf.
• Can function as a sound modem using an external USB OTG audio adapter or the phone’s built-in mic and speaker.
• Compatible with FreeDV protocol voice communication over HF transceivers.
• Controls external transceiver PTT using USB serial CAT (or VOX if CAT PTT is unavailable).

Requirements

To use codec2_talkie, you need:

• Android 7.0 (API 24) or higher.
• A KISS protocol-supported modem or transceiver that processes Codec2 audio frames over serial Bluetooth, BLE, USB, or TCP/IP.
• An analog transceiver with USB audio and VOX/USB CAT PTT control (e.g., MCHF or ICOM IC-7×00 series).

This application can also be installed on Android network radios, such as the Inrico TM-7.

Dependencies

codec2_talkie integrates several open-source components for seamless operation:

• Codec2 codec: https://github.com/drowe67/codec2
• Android Codec2 wrapper: https://github.com/UstadMobile/Codec2-Android
• OPUS codec: https://opus-codec.org
• Android USB serial library: https://github.com/mik3y/usb-serial-for-android

Related Hardware and Software Projects

Hardware

• ESP32 LoRa APRS modem: https://github.com/sh123/esp32_loraprs
• ESP32 LoRa DV transceiver: https://github.com/sh123/esp32_loradv
• Arduino Micro KISS modem: https://github.com/sh123/micro_loraprs
• ESP32 Arduino Codec2 library: https://github.com/sh123/esp32_codec2_arduino

Software

• FreeDV TNC: https://github.com/xssfox/freedv-tnc
• FreeDV data modem UI: https://github.com/DJ2LS/FreeDATA
• FreeDV GUI: https://github.com/drowe67/freedv-gui
• M17 protocol version: https://github.com/mobilinkd/m17-kiss-ht
• Codec2 iOS wrapper: https://github.com/Beartooth/codec2-ios

Conclusion

codec2_talkie is a game-changing Android application that enables amateur radio operators to experiment with digital voice communication using low-cost hardware. Whether you are using LoRa, FreeDV, AFSK, or other KISS-enabled modems, this app provides an excellent platform for voice and data exchange over APRS and other digital communication modes.

With its support for Bluetooth, BLE, USB, and TCP/IP modems, along with APRS and FreeDV capabilities, codec2_talkie is an essential tool for hams looking to explore the future of digital voice communication.

For more information about FreeDV and Codec2 visit https://github.com/drowe67/codec2

For more information about OPUS codec visit https://opus-codec.org/

For detailed information about this project https://github.com/sh123/codec2_talkie