Catch the RAJ9

The python script we used to track the RAJ9 High Altitude Baloon from OK1RAJ (https://ok1raj.cz/) during Maker Faire Prague Online 2020 (https://www.makerfaireprague.online/). It can send the gathered information to a specified telegram channel or show the possition in a live map.

NOTE: The thing is pretty hacky, we wrote it overnight. We just thought we would put it out there in case it could be useful to someone.

Requirements

• Software Defined Radio - RTL-SDR or similar
• SDR control program - GQRX or similar
• FLDIGI or even better dl-fldigi for uploading to habhub.org at the same time
• the script also relies on the awesome pyfldigi, crccheck and optionally python-telegram-bot and selenium python modules.

Setup

1. connect RTL-SDR
2. start GQRX and configure the correct frequency and modulation
3. start FLDIGI/DL-FLDIGI
4. set the correct decoding parameters in FLDIGI/DL-FLDIGI settings, in case of RAJ9 set the following parameters:

Modem/TTY/Tx:
       Carrier shift: Custom
       Custom shift: 540
       Baud rate: 100
       Bits per character: 7
       Stop bits: 2
       Filter Adjustment: 1.3

5. configure the XML-RPC API in FLDIGI/DL-FLDIGI settings:

    On fl-digi latest:
       Miscs/TCP-IP sessions:
           Lock: false
   On dl-fldigi:
       Rig/XML-RPC:
           Use XML-RPC program: true

6. It should work now! Start the script.

If you want to use the telegram feature, you will have to set a valid bot key in the program. If you want to use the live map view feature, you will have to get a geckdriver executable.