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I have a plane with two elevator servos and have mixed elevator with aux 2. The issue is when i use the elevator trim it only trims the elevator input side. How do i get the slaved elevator to trim with the master? Thanks!

The radio has a built in dual elevator setup that will make the trim work. You'll need to change some things in your setup. First is to go into the system menu and basically inhibit all the channels above #4. Then do the model setup with the dual elevator servos selected. The radio will select the second channel and mate it to the primary. Sorry but I do not remember what is the default second channel for the elevator.

You need to do all the primary control setups first this way as if the channel the radio want's to assign is not "Inh", it will see the channel as in use and not available. Also, certain mix numbers will allow certain channel combinations and they are not all the same. Last, some switches can be assigned to almost any channel while others are restricted to certain channels.

Zeeb is correct, the way to set that up is called mating that way any mixes or trims applied to the master will apply to the slave equally

Got it. It is working perfectly now! Thank you!