Receiving Meteorological Weather Balloon / 

Radiosonde using RTL-SDR.

 

In Mumbai, meteorological weather balloons or Radiosonde is launched twice daily at 5AM and 4:30PM IST. It can be received using RTLSDR at around 402MHz.  Received signal is very strong and any external VHF antenna would suffice . Weather balloon transmits information in digital format and requires PC with software like Sondemonitor  to decode information. This software also allows us to track weather balloon in real time using Google Earth ie using its GPS data. Flight time is roughly around 2hours.

Everyday flight report of weather balloons launched all over India by IMD can be checked here.

Tutorial for receiving weather balloon using RTL-SDR can be found here.

Few screen shots of my reception shown below, using cheap RTL-SDR, costing 7$ on ebay,com and VHF (QFH) antenna.

I received Weather balloon signal using my both setup. RTL-SDR &  UHF receiver

RTL SDR directly connected to antenna (VHF Pre-amp bypassed). 

Tested using UHF receiver. Please note frequency for most of the time in Mumbai is 402.8625MHz and Modulation is  "FM" & NOT "NFM"

Listen to audio file. Please reduce volume of your PC.

   

 

                                               Radiosonde Ascending & Gaining Altitude

                           Tracking Radiosonde in real time using Google-Earth

     Radiosonde almost reached altitude of 38KM and started descending after burst

 

                                          Other parameters from Radiosonde