Products of G4FON Software
Naturally, with the Koch method, you'll be copying random groups of characters, rather than words, until you've mastered the entire character set. These groups of are of random length, rather than a constant stream of five-character groups, to ease the transition from random groups to actual words. Yes, there is a difference in the rhythm.
Freeware download of G4FON Koch Method Morse Trainer 9. 2. 2004, size