Operation Manual

ROYAL SX
20
9.5. Plastic stick top with three but-
tons: installation and functions
If your model features important supplementary func-
tions, the long stick top with push-button / switch
(# 7 5303, supplied with the transmitter) may be use-
ful, as it provides a fast, simple and reliable method of
operating such functions without having to let go of
the stick.
Fig. 9.5.1. Fig. 9.5.2.
The top button KTa has a momentary function.
The two side-mounted buttons to-
gether form the switch KSw.
This stick top is connected to the
transmitter electronics by means
of two wires. The button and the
switched function can be assigned
to transmitter controls and
switches using the same pro-
cedure as for the other buttons (H
and M) and switches.
Fig. 9.5.3.
Fitting this stick top is quick and simple, and requires
no soldering:
a. Switch the transmitter OFF and remove the stick
top.
b. Locate the two connecting wires attached to the
stick top with the push-buttons, slip them through
the locking nut and the stick shaft ( Fig. 9.5.4.),
then install the stick top exactly as described in
Chapter 9.4.8.
 Tip:
You will find it easier to thread the wires through
the stick shaft if you curve the cable ends slightly
and hold the stick in one corner position.
c. Clip the wires from the stick unit in the holders de-
signed for them. Check that the cables have plenty
of ‘elbow room’ when you move the stick, are
never under tension, i.e. they cannot become
trapped at any position of the associated stick.
d. Locate the appropriate screw clamp terminal block
on the main circuit board, and run the bare wire
ends to the clamps ( Fig. 9.5.5; small slot-head
screwdriver required) from the transmitter battery
side; you will need to remove the battery before
doing this. The two wires can be connected to ter-
minals C and D either way round.
Fig. 9.5.4. Fig. 9.5.5.
!
Note: calibrating the stick buttons
When a stick top with push-buttons is first connected
to the transmitter, the software carries out an auto-
matic calibration process. If you need to replace the
stick top for any reason, a re-calibration must be car-
ried out; this will only occur if you reset the original
calibration using the PC program “ROYAL SX-
DataManager” ( 20.2.). For more information on this
procedure please refer to the instructions supplied
with the “DataManager”.
9.6. Digital trims
9.6.1. General information
The term “trimming” refers to the following procedure:
For example, you want your model aircraft to fly
straight and level when you leave the sticks exactly at
centre. If this is not the case, and the model always
tends to turn in one direction, you can adjust the neu-
tral point of the corresponding control function (in our
example Rudder) to “trim” the model accurately.
The ROYAL SX features digital trims on all four axes
of the primary sticks.
The ROYAL SX exploits the “Centre Trim” principle,
i.e. trim corrections only affect the area around the
centre point of the transmitter control, without affecting
the end-points of the travel. Compared with “standard
trims” this offers the advantage that full transmitter
control travel (and thus servo travel) is always avail-
able, because no reserve has to be provided for trim-
ming:
Dead zone
not
accessible
Centre Trim principle
Trim
Untrimmed
Standard
trim
Top
end-point
Bottom
end-point
Stick travel
Servo travel
Standard trims:
If you move a stick with standard trims to the right, the
servo reaches its upper end-point before the stick
reaches its own end-point, as shown in the diagram
above. This means: a dead-zone at the stick.
KSw '
KSw #
C D