Search for SP-VONT radiosonde

Last Sunday took to stratospheric heights. An SP-VONT stratospheric radiosonde took off from Malé Bielice Airport near Partizánske. Its launch was organised by the Slovak Organization for Space Activities and the agency placed a number of experiments on board. The whole flight was organised in cooperation with the Valašské Meziříčí Observatory and VZLU Prague. Our radio club ensured the collection at the landing site and handing over to the owner.

Radiosondes are used to measure the atmosphere. During flight, they measure the pressure, temperature, humidity, direction and the speed of wind and send this data to the ground. A radiosonde is suspended under a balloon, which is filled with hydrogen or helium and can reach an altitude of up to 30 km. However, in addition to the radiosonde, a load can also be suspended under the balloon. This is mostly a special measuring device for data collection within a research project. The SP-VONT radiosonde carried a device for the collection of dust particles from decayed meteorites. At high altitudes, there is a lot of dust coming from the open space. Experimental electronics and a special particle detectorwere also on board.

After launch, the radiosonde flew in the southeast direction. The preliminary impact site was calculated to be around the village of Tokaj, near the town of Miskolc in Hungary. The radiosonde transmitted its location using the FSK – RTTY modulation, thanks to which we knew its position and height. To receive the signal, we used a 10el antenna on the 432 MHz band, a YAESU FT857 radio station and a dl-fldigi program to decode the signal. Despite the signal failure before landing, we were able to successfully track the radiosonde and help deliver the experiments to the laboratory on time.

It was a new experience for us, and we are pleased to have been part of this mission. Based on this activity, we decided to build an autonomous receiver station for radiosondes with automatic data sharing on the Internet. Finally, a few photos from the collection of the radiosonde.