Swashplate; Gyro; Tail Curve; Mixing - Spektrum DX20 Instruction Manual

HELI (HELICOPTER)

Swashplate

The Swashplate menu option enables you to adjust the following:
• Swashplate Mix
• Exponential
• E-Ring
• Elevator Compensation
Use positive or negative Swashplate mix values as needed for
correct direction response of the helicopter.
Before making adjustments to the Swashplate mix, make sure the
throttle/collective pitch input moves the entire swashplate up or
down. If the servos are not moving in the same direction, reverse
them as necessary in the Servo Setup menu option.
When the entire swashplate moves up or down:
1. Adjust the mix value for the Aileron and Elevator channels. If
the servos do not move in the correct direction, change the
direction of the mix—for example, a positive value instead of
a negative value.
2. Adjust the mix value for the Pitch. If the swashplate does not
move in the correct direction, change the direction of the value
(negative instead of positive).

Gyro

The Gyro menu option enables you to assign a gyro gain value
to an independent switch or a Flight Mode. Assign the receiver
channel connected to the gyro, then assign the switch for gyro
options. You can also assign values to available switch positions
(from 1 to 4 rates are available, depending on the switch
assigned). Make sure the gyro operates correctly and compensates
in the correct direction.

Tail Curve

The Tail Curve function mixes tail rotor input with the throttle/
collective function to counter torque from the main rotor blades
when using a non-heading hold (tail lock) gyro or when using
rate mode on a gyro. See Pitch Curve for more information on
programming curves.

Mixing

Cyclic to Throttle
Cyclic to Throttle mix prevents rpm loss when aileron, elevator or
rudder inputs are given. This mix advances the throttle position
with cyclic or rudder control to maintain rpm. At full throttle, Cyclic
to Throttle mixing prevents the throttle from over driving the servo.
IMPORTANT: Do not use Cyclic to Throttle mix when using a
governor.
To verify that the Cyclic to Throttle mix is working properly and in
the correct direction, move the flight mode switch to one of the
active positions. Move the programmed cyclic or rudder channel,
noting the throttle position. The throttle position should increase.
If the throttle decreases, then the opposite value (positive vs.
negative) is needed.
SPEKTRUM DX20 • TRANSMITTER INSTRUCTION MANUAL
Always enable Expo when using a standard rotating-arm servo.
The Expo delivers linear movement of the swashplate from a
standard rotary servo. When Expo is inhibited, the arm on a
rotary servo moves on a curved path with decreased swashplate
movement at the extremes of the servo arm travel.
NOTICE: Do not enable Expo when using a linear servo.
Electronic E-Ring
This feature prevents over driving servos by limiting servo travel if
the sum of your cyclic and pitch inputs exceeds servo limits.
Swashplate
The Swashplate Mix typically corrects swashplate timing issues by
mixing Aileron to Elevator and Elevator to Aileron. When adjusted
correctly, the Swashplate causes the helicopter to roll and pitch
accurately with minimal interaction.
EN
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