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Old 04-02-2021, 02:30 PM   #3 (permalink)
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Hello in my spektrum dx9 black edition if i I press the elevator stick in one direction, in the section monitor the cursor it moves one way.
Now if i press trim elevator in the same direction as the stick, in the section monitor the cursor moves in the opposite direction.
So if I press the trim the servo moves in the opposite direction.
I have memory helicopter with flat 120 degrees.I fly in mode 1.
Help me please
With the DX9's "Swashplate Type" set to "3 Servos 120" implies you are flying a flybar equipped helicopter.
If you don't have a flybar and are not using an Align 3GX, "3 Servos 120" would be the wrong DX9 "Swashplate Type" to use for almost any modern FBL flight controller.
Assuming you are flying a flybar equipped helicopter, "3 Servos 120" should not change how the trim works in relationship to the collective or cyclic stick's function.

If you are looking at the DX9's "Monitor" screen, you are seeing what the servos are doing and not what the functions are doing.
That seems confusing, but you have to understand that the 3 servos that are connected to the swashplate are NOT the elevator, aileron and pitch servos.

The transmitter is reading the movement of the collective and cyclic sticks and then mixing the 3 swash servo channels together to move the swashplate to match what the sticks are commanding.
EG: If you pull back on the "elevator" stick (aka: "back cyclic"), 1 of the servos will move "up" and 2 of the servos will move "down" to tilt the typical swashplate backwards.

Look on Wikipedia for "RC helicopter eCCPM" (electronic Cyclic, Collective, Pitch Mixing) for a more complete description.
The "collective" and "cyclic" are functions that are assigned to sticks on the transmitter and not directly related to the servos on the helicopter.

Keeping in mind that the "Monitor" screen on the transmitter is showing you the servo directions, and with the typical swashplate servo setup, it is likely that 1 or 2 of the swashplate servos may have needed to be reversed when the heli was initially setup and that may cause more confusion.

So it is possible that moving the "cyclic" or "collective" trim may cause 2 or 3 servos to move but some may move up and some may move down (as seen on the "Monitor" screen).

The real question is: What is happening on the swashplate when you move the Collective or Cyclic sticks and trim levers?
If everything looks right and it flies okay, then all is good.
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Last edited by ticedoff8; 04-02-2021 at 02:55 PM..
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