E-flite Ultimate 20-300 10 ARF - Manual (Page 33)

33 E-flite Ultimate 20-300 Assembly Manual
Control Horn Length
This length is also very critical. The closer the pushrod
attachment is to the surface the LESS mechanical advantage
you have on the surface.
In the case of the Ultimate these lengths have been set for you.
In general, practice never set the control horn any shorter than it
needs to be for the surface to have full deflection at the servo's
full travel.
Travel Adjust
The travel volume of the servo is not only controlling how far
the servo travels. It also has a large impact on the resolution
of the servo. On any precision/3D airplane you want to keep
the travel adjust percentage at 100% minimum. However, it is
more optimal to have the final throws of your servo to be set
around 125–135%. This will increase the resolution and torque
delivered to the surface and improve the feel of any airplane.
To set up the Ultimate properly when using the Spektrum DSP75
digital servos, it will be necessary to use the Spektrum Digital
Servo Programmer (SPMDSP). This programmer allows you to
increase and optimize the maximum allowable travel of the
servo (the stock programming of the servo does not allow for
enough travel, even when 150% ATV is used).
Please follow the steps that follow to achieve the correct and
optimum servo and linkage setup for Ultimate 20-300.
Note: The correct servo arm lengths and control surface
travels are listed below these steps.
 1. Set the nylon screw lock connector at the correct
position/length on the servo arm according to the
measurements on the next page.
 2. Attach the pushrod and clevis to the outer-most hole
on the control horn.
 3. Center the servo and attach the servo arm so it is
parallel to the hinge line.
 4. Insert the pushrod into the screw lock connector.
Center the control surface and tighten the screw down
to hold the pushrod in place.
 5. Connect a battery and servo to the programmer.
 6. Use the programmer (according to the instructions
included with the programmer) to set the center and end
point travel of each servo. Use the measurements listed
for the throws set by the programmer
Note: You are not setting the full and final control
throws/deflections at this time. The full control throws/
deflections will be adjusted by the use of the travel
adjustment in your radio in the next step because there
is a difference in the amount of travel achieved with the
programmer and transmitter.
 7. Now plug each servo into the receiver and use the
travel adjust function of radio to increase the travel of
the servos to the final control throws/deflections. This will
allow you to raise the travel adjust percentage in your
radio to the suggested 125–135%.