Repurposing Vaisala RS41 radiosondes for amateur radio high-altitude balloon tracking

Repurposing radiosondes for amateur radio high-altitude balloon tracking was a presentation I gave at VUSHF2022, the 42nd Nordic V/U/SHF meeting held between 26th and 29th of May 2022 at Kristalliranta, Säkylä, Finland. The presentation describes the hardware of Vaisala RS41 radiosondes, discusses why they are useful for amateur radio hobbyists and, finally, gives instructions on how to find your own radiosonde - an STM32 microcontroller board fallen from the sky! The presentation slides are available here for download.