OpenTX Trims to subtrim

[Fletch]

When I setup my tricopter with the integrated naze last week none of the sticks were reading 1500ont the clean flight setup page, even with the aticks physically centred, they were all just a few digits out. 

So I trimed the transmitter then wanted these changes to stick permanently
So started hunting down subtrim options ... found this video
https://youtu.be/0JK94n7gFLs

Hadn';t heard about this before and thought it may be handy for somebody else in the future

[kilby]

Took me a while to find on the Taranis, though once you find it its a doddle