A radio amateur (ham) has posted details online of how he used low-cost kits to develop an image transmission system to receive images from a balloon that operated at 30km.
He used the Slow Scan Television (SSTV) system, which is usually used by hams to transmit images over long distances, albeit at a low frame rate; typically 30 seconds to 2 minutes per frame.
The transmission system comprised a cheap walkie-talkie set operating on unlicensed spectrum and an ESP32-Cam to process and acquire the image, with the ESP32 encoding the image in the Martin 1 format that was developed by a ham named Martin (G3OQD).
The ham who posted the invention said the technique could be used in any situation where the sender wants to transmit an image over a communication medium.
