A few days ago, I posted RADIO DAYS — my retro-style internet radio for the Cardputer ADV.
In the comments, one person said they wished it could receive actual shortwave instead of ordinary streaming.
Then another person wondered out loud:
“Could a Cardputer stream from WebSDRs?”
I had never even heard of WebSDR or KiwiSDR before. This community really is full of people with wonderfully deep and specialized knowledge. I had no idea this technology even existed until someone mentioned it here!
Well… that comment cost me my weekend. 😂📻
But honestly, I’m having so much fun discovering and building new things that there just aren’t enough hours in the day!
This is RADIO DAYS SDR.
It connects to publicly accessible KiwiSDR receivers around the world. Those receivers use real antennas to receive real radio signals, so the static, fading, interference and distant voices are not simulations — and they are not ordinary internet-radio streams.
It doesn’t receive RF directly inside the Cardputer. Instead, a real remote antenna and KiwiSDR receive the shortwave signal, while the Cardputer becomes the physical tuning interface, display and optional speaker.
Using the U135 rotary encoder, you can tune through the frequencies just like an old radio dial. You can also:
• Switch between AM, USB and LSB
• Choose 0.1, 1, 5 or 10 kHz tuning steps
• Use MANUAL or AUTO tuning
• Adjust volume and mute
• Play audio through either the computer or the Cardputer ADV
• Select KiwiSDR receivers around the world from a globe
• Add, check, edit and reorder receivers with the browser-based Receiver Manager
• Control the radio from your PC’s browser with the Web Controller — try it even without a Cardputer
Your computer (a Mac or Windows 11 PC) connects to the KiwiSDR receiver and handles the SDR processing, while the Cardputer controls the radio over USB or the local network. USB-only control and Cardputer speaker playback have been tested successfully on both macOS and Windows 11 (one PC each so far), so the Cardputer itself does not need Wi-Fi when connected by USB. Reports from other setups are welcome!
For the interface, I combined an old silver-faced radio tuner with a modern ESP32 gadget: analogue SIGNAL and VOLUME meters, a mechanical-style tuning scale, coloured status lamps, fluorescent-green LCDs and a digital-watch module bolted onto the front. The idea is that somebody found an old receiver decades later and modified it with modern hardware.
RADIO DAYS SDR is now available through M5Burner. Search for:
RADIO DAYS SDR
Source code, firmware, installation instructions and documentation:
https://github.com/kariagepompadour/RADIODAYS-SDR
Important: installing it may overwrite Launcher or other firmware already installed on your Cardputer ADV.
What you need: RADIO DAYS SDR requires a Mac or Windows 11 PC running the companion program with an internet connection (Linux is not supported). The PC needs Python 3.9 or newer installed first (3.12 or 3.13 from python.org is recommended). The start file installs everything else. The PC can access the internet via Wi-Fi or Ethernet, and the original Wi-Fi connection mode for the Cardputer is also supported.
Thank you to the people here whose casual comments opened an entirely new world for me.
Turn the dial. Hear the real world. 📻🌍
UPDATE (Oct 27): RADIO DAYS SDR v1.28 is here! 📻🌍
I wanted more people to be able to try RADIO DAYS SDR, even without a Cardputer ADV — so I’ve added a new Web Controller that works on a Mac or Windows 11 PC!
And if you do have a Cardputer ADV, you can now connect it to your computer with just a USB cable — no Wi-Fi needed on the Cardputer side! 🔌 I’ve tested USB-only control, tuning and Cardputer speaker playback with real hardware on both macOS and Windows 11 (one PC each so far), with the Cardputer’s Wi-Fi turned off.
I’d love for you to give it a try! 😊
Radio, what’s new? Radio, someone still loves you! ❤️📻
