A retro shortwave dial for your pocket, built on Cardputer ADV

RADIO DAYS turns an M5Stack Cardputer ADV into a 1980s-style internet radio. A physical rotary dial tunes 42 stations across seven world locations.

Build sheet

Device page: M5Stack Cardputer-Adv →

Can I build this?Intermediate · AI 4/5 · $50–80

Difficulty: Intermediate
AI-buildability: 4/5
Time: A weekend
Cost: $50–80

Parts

M5Stack Cardputer-Adv M5Stack U135 rotary encoder 3D-printed tuning knob 3D-printed stand

Tools

3D printersoldering iron

Starter prompt

Based on "A retro shortwave dial for your pocket, built on Cardputer ADV" on Afterware: https://afterware.xyz/p/a-retro-shortwave-dial-for-your-pocket-built-on-cardputer-adv

Write Arduino firmware for an M5Stack Cardputer ADV that uses an M5Stack U135 rotary encoder as a radio tuning dial. Show a list of internet radio stations grouped by region, with a tuning scale and signal meter on the 240x135 screen. Turn the encoder to step through stations and stream the selected station over Wi-Fi.

Estimates based on the original write-up. How AI-buildability is scored. Building with an AI assistant? Connect it to Afterware (free MCP server).

Story

The tuning knob is the hook. Instead of picking stations from a list, you turn a physical dial, and the Cardputer's screen answers with a tuning scale, a signal meter and animated radio towers. A globe interface groups the 42 stations into seven locations, and the sky shows day or night with a sun or moon.

The build pairs the Cardputer ADV with an M5Stack U135 rotary encoder. A 3D-printed knob sits on a 3D-printed stand that holds the Cardputer and encoder together. Firmware is on M5Burner for standalone Wi-Fi playback, and a companion relay app on macOS or Windows can play the stream through a computer over USB instead.

It started as a side effect of the author's Cardputer Media Jog project, which also uses the U135 as a media controller. The idea is simple to steal: any encoder on a small screen can become a dial, and a dial makes browsing feel like searching for a signal.

Resources · 3

GitHub repository RADIO DAYS Web version Cardputer Media Jog hardware

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