This Project began to explore the use of the DVSI AMBE 2020 voice compression chip and also the ADF7021 single chip VHF RF Transceiver from Analog Devices.
The most likely direction is a re-spin of the board to add more user inputs like a key pad as well as split the RF section onto another board. This would be a more modular approach and allow a simple CMX589A modem chip to be used to interface to non-Icom FM radios.
Another output from this project will be a more detailed low level D-Star format description and open source code that others can use or build upon for their own projects.
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