Dansy,
I am using the REX12 in the Default mode with the 900 as the back up. I only have one receiver to bind for the 2.4. So far it is a simple hook up and it works at the field I fly.
Once I was learned that the 900 has to be set at PPM + it worked brilliantly.

Custmachr,
The firmware for the central box at the two places I have found (Esprit and Jeti Model)
only list the FW 1.20 for the CB200. I only found FW update 1.27 for the Mezon speed control. Maybe I was looking at the wrong website?


I did have an M-Flow connected to the CB200 at first, I then wanted to reroute the extension so I unplugged it. I left it unplugged until I could make a new longer extension. And it was plugged in correctly. It was powered up for about 5 minuets but I never did check the CB200 in device explorer. Could a bad M-flow sensor temporarily knock the CB200? Just a thought I had. My apologies for not mentioning this in first post, at first I didn’t think it was or could be the problem. Then..... yes maybe it could be! Sometimes it seems as though the simplest things end up being the issues with the biggest headache.
So I have made some progress, I deleted the model in the transmitter and started over from scratch. So far the CB200 is now being recognized and is opening up. No ratchety servos. The 900 back up works as it should.
other than starting with a completely new model everything I did to bind and set up the receivers is exactly the same as the few times ( understatement).
I will not plug in any telemetry items until the set up is done, so I can verify that the system is still working correctly. I’ll keep this group informed as I continue.
Thanks