No. no. no. no, and NO. Is that clear enough? Do NOT mix DSMx and DSM2 receiver components in the same installation.
This is NOT a 3GX limitation, it is a SPEKTRUM REQUIREMENT.
No matter if you are using s standard receiver with satellites, a FBL system with satellites...you DO NOT MIX DSMx and DSM2 receiver components.
Although DSMx receivers are fully compatible with DSM2 transmitters (they will work in DSM2 mode), and DSM2 receivers are fully compatible with DSMx transmitters (they will work in DSM2 mode), DSMx receiver components are NOT compatible with DSM2 receiver components. DSM2 receiver components are NOT compatible with DSMx receiver components.
Spektrum goes out of its way to clearly state that you do NOT mix the two types of protocols in the same setup. You are pretty much guaranteed a crash.
If you have a DSM2 receiver needing a satellite, use ONLY a DSM2 satellite with it. If you have a DSMx receiver needing a satellite, use ONLY a DSMx satellite. If you have a multi satellite installation, do NOT mix satellite types.
Satellite receivers are full-range, full feature receivers. They lack the big connector block to hook up to servos, instead they communicate over a three wire serial data bus. The DSMx and DSM2 protocols and data on that 3-wire bus are not meant to operate in the same environment with each other at the same time.
For a moment, consider what will happen at binding time if your transmitter supports DSMx protocol. The DSMx satellite would be happy to bind in DSMx mode while the DSM2 receiver would want to bind in DSM2 mode. Which mode would the transmitter choose as it can't bind in both?
Those who have gotten away with a mix are living on borrowed time. Spektrum tells you NOT to mix them for a sound reason.
Also, when binding through the 3GX unit, there are two different binding procedures to use to tell the 3GX which protocol it will use. With a mix of satellites and a transmitter that could support either, again, which gets chosen?
Just say NO. Either two DSMx satellites, or two DSM2 satellites. Never one of each.
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