Displaying eQSL Cards
Electronic QSL cards are digital versions of QSL cards for confirming QSOs, with the most popular service for exchanging these being eQSL.cc. Unlike other electronic/digital means of confirming contacts, like LoTW and QRZ.com, they have a traditional postcard style, which can be customised by the sender, often including images of where they live or their shack.
Unfortunately, like many digital images, unless you take the time (and money) to print them, they often don't get displayed anywhere. Digital photo frames are a solution to this, but then you have the time and hassle to keep a memory stick/card updated with images.
One solution to this problem is to have a device which acts like a USB memory stick, but with it's own WiFi connection, download the latest eQSL cards directly. This could then be used with any digital photo frame and operator autonomously.
Another goal was to make it simple so anyone could create one, with off the shelf parts if possible. Luckily, the LILYGO® T-Dongle ESP32-S2 Development Board was a ideal solution to this, offering SD card interface for storing images, USB-A port for plugging into digital photo frames, and added bonus of a TFT screen to display status messages.
Software has been created, using the Arduino development environment with ESP32-S2 core, using the eQSL API in order to fetch images, all running on the device itself. Other than the initial flashing and configuration (WiFi and eQSL credentials), the device operates independently, able to be powered directly from USB port of the digital photo frame.
Here is a picture of a dongle, showing it currently downloading a eQSL card:
And it in action plugged into digital photo frame:
The USB device is only around 15 USD, and as digital photo frames can be purchased cheaply second hand from sites like eBay; an auto-updating eQSL digital display can be put together for very low cost. The component list, installation instructions, and software binaries (and source code) can all be found on a GitHub repository if you are interested in making your own.