The Vaisala RS41 is the radiosonde which is operationally used by Deutscher Wetterdienst and Bundeswehr. In germany, the transistion from it’s predecessor, the RS92 happened in 2016 through 2017. Here, the RS41-SGP with barometric pressure sensor is used.
The sonde is better reusable than it’s predecessor. A GPS with full feature set is onboard, as well as a radio IC, which is capable of transmission in the 70 cm amateur radio band and in the 433 MHz ISM band. The MCu is a STM32, the power supply consists of 2 AA lithium primary batteries. For wireless groundcheck, there is a NFC interface.
Reverse Engineering of the sonde is organized in multiple GitHub-Repositories.
I hope to also provide PTU calculation and NFC interface at one day, but this is nowhere near finished yet.