Morse Trainer — CW You Can Hold

Morse code is learned with a key under the hand, in short sessions and through repetition. This battery-powered device keeps the phone out of the loop: it fits in a jacket pocket, accepts a straight key or paddle through a 3.5 mm socket and can be used silently while travelling.

Lessons support both a conventional sequence and the Koch method. Listening and sending progress separately, while three configurable training modes cover character recognition, keyed sending with live timing evaluation and continuous copy with synchronized text.

Five two-player games turn drills into competition, including a dog race, lighthouse signalling and a flood-control game. Progress and statistics for two users live on the microSD card, while a local Wi-Fi interface manages practice texts, settings and results.

Inside is a Waveshare ESP32-S3 touch board, LVGL interface, audio amplifier, speaker and 3D-printed enclosure. Timing, keyer, decoder and game logic are separated from the hardware layer so the core can be tested on a computer without the device attached.