In order for the Turnigy9X radio transmitter to work with the Pixhawk flight controller, there are two main settings that need to be set; the first is the AUXILARY CHANNELS and then the MODE TYPE (Heli, Acro, Glider). By default the auxilary channels (channel 5 through to channel 9) are set to NULL and must be changed to be activated. Secondly, the Pixhawk flight controller only understands the signals from the mode type, "ACRO" or airplane, so if you make the common mistake of setting the radio to "HELI" or helicopter (which makes sense to quadcopter pilots), the radio won't work with the Pixhawk and you'll begin to think that the Turnigy9X radio is not compatible with the Pixhawk flight controller, which is not the case at all!
Setting the Auxiliary Channels
When you first power on your Turnigy9X transmitter by default you are brought to the welcome screen (above photo). To setup the AUXILIARY CHANNELS, we must go to the function settings. To do this press the MENU button on the right of the screen and then press the UP key on the pad to the left of the screen to highlight the function settings or FUNC SETTING (below photo) icon.
Once the function settings (FUNC SETTING) icon is highlighted, press the MENU button to go to the function settings (FUNC SETTING) menu options. Press the DN (down) key on the keypad to the left of the screen and move through the menu selections until you come to the [AUX-CH] option (above photo). Press the MENU button on the right to enter into the options for this selection. By default all of the auxiliary channels (channel 5 through channel 9) are set to NULL (below photo) and need to be setup.
Press the "+" (plus) key on the keypad to the left of the screen and move through the selections (GEAR, PIT TRIM, HOV THRO, HOV PIT) for channel 5. Select, "GEAR". (If you go too far along use the "-" (minus) key on the pad to move back to the previous setting.) Once GEAR is highlighted, press the DN (down) key on the pad to move to channel 6 and so on. As you move through each of the remaining channels, set each to GEAR. Once each channel has been set, you must press the MENU button again until you are returned to the previous menu. If you press the EXIT button, you will also be returned to the previous menu BUT your settings will not be saved. You must use the MENU button to exit and save your settings! Once you have returned to the function settings menu options (the highlighted [AUX-CH]), use the EXIT button on the right of the screen to return to the first function settings menu (below photo).
Now we are ready to setup the mode type in the SYSTEMS SETTINGS.