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desk-toy

USB‑C, hand‑solder desk toy that flashes an LED when it hears a sharp sound — a mic front‑end and a 555 timer fire a ~2.4 second "lightning flash."

A USB‑C powered, hand‑solder Morse code learning tool — taps on the capacitive touch pad like a telegraph key; an ATtiny85 decodes the dots and dashes, sounds them on the buzzer, and shows the message on a 5x7 LED matrix via the MAX7219.

USB‑C, hand‑solder desk toy that rolls two six‑sided dice — an ATtiny85 watches a light sensor and shows the result on a 12‑LED bar display.

USB‑C, hand‑solder countdown toy — an ATtiny84 drives a single 7‑segment digit and a piezo buzzer through a rocket‑launch countdown.