CRT BOY Combines a Tiny CRT and ESP32 into the Coolest Game Boy Ever

Small displays these days are astoundingly affordable, and even the cheapest LCDs are thin, light, power-efficient, and have decent resolutions. With tech like that at our fingertips, it’s hard to imagine a CRT ever being remotely practical. Luckily, practicality isn’t a constraint makers need to concern themselves with, and so we get fantastically cool builds like luni’s CRT BOY.

Some of you may remember Luni, of the YouTube channel bitluni’s lab, from his ESP32 composite video project that we featured earlier this year. That build proved that it’s not only possible, but relatively easy to output composite video from an ESP32 to an analog CRT television. The CRT BOY takes that concept to its logical conclusion in the form a portable CRT Nintendo Game Boy.

This project started when Luni received a miniature black and white CRT from a fan, which was originally part of an intercom system. Surprisingly, the CRT was manufactured in July 2007, and has straightforward inputs for the power and video signal. The only other connections are to adjust the brightness and contrast of the display.

Connecting the ESP32 to the CRT followed the same basic process as Luni’s ESP32 composite video project. The CRT’s 12V power comes from a LiPo battery, and a regulator brings that down to the 5V required for the ESP32. From there, Luni just loaded up a Tetris clone for the ESP32, connected an NES controller, and he was gaming on a CRT handheld console! Now all he needs to do is design a 3D-printed case for the CRT BOY.