The 3GX, with Version 4.0 software installed, fully supports DSMx protocol.
All versions PRIOR to V4.0 only support DSM2 protocol, however a DSMx receiver/Transmitter pair will work just fine, but in DSM2 mode.
To BIND your DSMx radio with DSMx satellites using V4.0, you install the bind plug on the setup as usual, BUT when you apply power to the 3GX setup, you have to hold the button on top of the 3GX as you apply power, to tell it to bind in DSMx mode.
This is clearly explained in the PC software that accompanies V4.0.
(While reading about binding, check out the options for failsafe setup, as well).
If you simply install the bind plug and apply power WITHOUT holding the button down, it will bind in DSM2 mode.
You MAY have to set your TX to 22 msec instead of 11 msec frame rate when binding in DSMx mode. (I've had the opportunity to bind a couple for some friends who own DSMx stuff, and as I remember, the frame rate of 22 msec needed to be chosen). I may be wrong on this particular point, however. If someone can clarify for me, please do.
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