In this tutorial video I go through the process of setting up a quadcopter with flight modes and switch sounds on your TX16S in OpenTX Companion and on the radio. This may not be exactly the same set up you want but I think it is a good starting point. Remember this is on the radio side of the set up you still need to go through the Betaflight settings.
I purchased my TX16S from the Flying Robot Co in Cape Town. This is not an affiliate link but I want to share where you can get yourself a RadioMaster TX16S in South Africa.
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