Display structure
Line 1 always displays the name of the selected servo (in
our example the Aileron servo). Above the graph the
channel number of the selected servo is shown (exam-
ple: SERVO: 1 ).
The numbers 1 ... 5 below the graph (X-axis) correspond
to the servo calibration points P1 ... P5 .
Parameter: REV. (servo reverse)
16.1.1.
To reverse the direction of servo rotation simply select
the REV. parameter and press the ENTER button or
one of the two 3D digi-adjustors. The cursor changes
to the value rev (servo rotation reversed) or nor.
(normal servo rotation). To reverse the servo's direction
of rotation simply press the REV/CLR button:
the curve is "reversed";
the value changes from rev
Parameter: P1 ... P5
16.1.2.
You can carry out several tasks by adjusting the servo
calibration points P1 ... P5 .
In detail these are:
setting the maximum working range of the servo. The
values P1 and P5 set here (servo end-points) are
never exceeded (limit values). This serves to protect
the servos from mechanical stalling at either end-
point / maximum travel;
setting symmetrical control surface travels;
matching the travels of multiple servos to each other
(e.g. two aileron or two elevator servos), so that the
control surfaces work exactly in parallel;
compensating for mechanical discrepancies in the
control surface linkage. Using the intermediate points
P2 and P4, for example, it is possible to match the
travel of two control surfaces accurately between
servo centre and servo end-point;
setting deliberately non-linear servo travel (= curve),
e.g. for the throttle servo in power models, in order to
obtain a linear speed change over the full range of
throttle control (throttle curve).
This is the procedure for calibrating a servo:
1. Servos which are operated directly by transmit-
ter controls e.g. Aileron, Elevator, Rud-
der, Throttle, L.gear , ...
Check first that the direction of rotation of the servo
matches the movement of the transmitter control.
If necessary, reverse the direction using the REV.
para-meter (
16.1.1.).
Important: if you subsequently reverse the direc-
tion of servo rotation, it will be necessary to repeat
the calibration process.
nor.
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ROYAL evo 7 - Instructions
2. Servos which are controlled by mixers
e.g. AILERON+ , DELTA+ , V-TAIL+ , ...
With these servos the direction of servo rotation is
initially irrelevant, as the correct direction for the
control surface movement will be set later during
the mixer set-up process.
Exception: the following servos in model helicop-
ters:
HEADle , HEADri , HEADf/r , TAIL , ...
3. Select one of the calibration points P1 ... P5 and
activate the % value using the ENTER button, or by
pressing one of the 3D digi-adjustors. Now press
the digi-adjustor assign button < F >.
Regardless of the position of the associated trans-
mitter control, or any control and mixer settings,
the servo now automatically adopts the position
corresponding to the percentage figure at the se-
lected calibration point. With one hand you can
now measure and check the control surface travel
easily and conveniently (ruler, venire calliper), while
the other hand remains free, so that you can alter
the value using the UP / DOWN buttons (
one of the two 3D digi-adjustors.
Multiple servos (e.g. all Aileron , all DELTA+ , all
HEAD servos, ...) automatically adopt the same posi-
tion; these should run in the same direction as the
selected servo after you press the digi-adjustor as-
sign button < F >. If this is not the case, the direc-
tion of servo rotation must first be reversed using
REV. (
16.1.1.).
When the travel is correct, press the digi-adjustor
assign button < F > once more. The servo now
takes up the position corresponding to the associ-
ated transmitter control.
Press the ENTER button or one of the 3D digi-
adjustors to conclude the set-up process for the se-
lected point.
The number of variable servo calibration points (min.
two, max. five points) varies according to the setting
you selected when you assigned the servo (
!
Note:
The servo calibration facility should only be used for
fine-tuning the system. We strongly recommend that
you start by carefully adjusting the mechanical system.
You should never reduce the servo end-points P1 and
P5 by more than about 10 ... 20%, otherwise you forfeit
a proportion of the servo's full power, servo accuracy is
reduced, and the effect of servo gearbox play is exag-
gerated. It is equally important that you should not
change the servo centre setting by more than about 10
... 20%, otherwise the servo will exhibit non-linear run-
ning characteristics in both directions.
TIP: Vertical reference line
The dotted vertical line in the graph is simply a guide,
indicating the current position of the associated trans-
mitter control. If you have activated a value using the
digi-adjustor assign button < F >, the vertical line
jumps to the corresponding point and remains there
until you press the assign button again, or move the as-
sociated transmitter control.
/
) or
16.2.).