I ordered some new RFD900X radios for some new copters.
I discovered that RFDesign upgraded the hardware - there are now V1 and V2 hardware versions.
I loaded the latest firmware for each - and found that they won’t connect to each other.
The version numbers can be seen in very small letters - a kind fellow send me a photo to show where to find the markings:
I’ve sent a message to RFDesign to see if there is a way to address this problem.