Carl Goldberg GPMA1956 Eagle 2 ARF - Manual (Page 33)

33
The transmitter is the part of the radio that the pilot holds.
It usually consists of two sticks that can be moved in 360°
circles, along with slide tabs that help center each move-
ment of the stick for each servo. The following diagrams
illustrate how the radio stick movements control the servos
and the movements of the control surfaces on the aircraft. SERVO MOVEMENTS
As mentioned in the introductory section of this book, radio
systems with "servo reversing" simplify radio installation.
With a non-reversing system, each pushrod must match its
corresponding servo's rotation. With "servo reversing,"
pushrods can be hooked up to either side of the servo's
output wheel, and after checking the control response, a
servo responding in the wrong direction is easily switched
to the correct action. See your radio manufacturer's
instructions for more detailed information.
The following procedure will help you set up and fine tune
your radio system.
First, remove all servo arms and wheels.
THROTTLE SERVO
1.
Turn on the transmitter (Tx) and receiver
(Rx).
2. Move the left stick of your Tx all the way
up to the top of its movement. This stick should have a
ratchet feel to it and will stay in any position, up or down,
in which it is placed. In addition, move the trim tab, locat-
ed to the right of the throttle stick, all the way to the top of
its movement.
3.
Move the throttle pushrod until the engine
carburetor is open all the way.
4.
Remount the servo arm back on the throt-
tle servo, but do not put the screw back in the center of the
arm at this time.
5.
Move the transmitter throttle stick all the
way to the bottom of its movement and observe the open-
ing in the carburetor. The opening should be 1/16" to 1/8".
If, on the other hand, the carburetor is full open, find the
radio's servo reversing switch (see radio instructions) and
switch it.
If the servo is moving in the right direction,
but the movement is not enough, change where the
pushrod is mounted on the servo arm so that the amount
of movement that the pushrod gets from the servo is more
or less. The farther out from the center of the arm that the
pushrod is mounted, the greater the movement. For
example, if the carburetor opening was greater than 1/8"
when the throttle stick was all the way down, the pushrod
needs to be mounted further out on the servo arm; if the
opening was less than 1/16", the pushrod needs to be fur-
ther in on the servo arm.
In addition, most engines have two holes
on the throttle arm, where the pushrod is hooked up to the
carburetor. The farthest out hole gives the least move-
ment when the pushrod is moved.
6.
When the carburetor is opening correctly,
move the trim tab all the way down to the bottom of its
movement. The carburetor open should be completely
closed. This safety feature allows the running motor to be
turned off
RADIO, ENGINE & AIRCRAFT SET-UP