This real-time Morse decoder and trainer uses the Goertzel algorithm to detect a CW tone of 708 Hz. The program then analyzes the detected tone patterns in order to recognize and decode Morse characters.

The decoding is flawless if the input signal is itself flawless in every aspect. The speed can exceed 50 standard words per minute (WPM). However, on the always noisy HF bands the decoder is clearly inferior to a trained human ear. Still, at any given time one will find real CW transmissions that can be decoded with some success, although the results may vary from minimal to 100% accurate text.

The purpose of this decoder is not to discourage operators from learning Morse code but, on the contrary, to stoke their curiosity and give them a fun learning experience.

The decoder automatically adjusts to the transmission speed. 

The training mode helps the operator acquire a good sending style. The LCD indicates the speed and the characters sent (if correct). 

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