From Alex Wulff on Hackster.io:
MorseCard – A Tiny Telegraph Station
This small PCB lets you learn Morse code and communicate with friends. Set up a telegraph network in your very own home!
The source code is shared on GitHub:
AlexFWulff/MorseCard
AlexWulff has shared the project on OSH Park:
MorseCard LiPo
OSH Park 