GRAUPNER mx-16 ifs, Programming Manual

Page: 113 / 132

113 Programming example: F3A model
You may fi nd it necessary to assign transmitter controls
to particular inputs to operate the retractable undercar-
riage and carburettor mixture adjustment. This is carried
out in the...
»contr set.« menu. (page 58)
For example, you may like to assign a particular trans-
mitter control – perhaps one of the ON / OFF switches
SW 1 … 4 – to the input “I8” for the retracts, and a
proportional control – e. g. the INC / DEC button CTRL
6 – to the input “I7”, for mixture adjustment:
I6
I7
I8
+
t r v
100% 100%
100% 100%
100% 100%
SEL SYM ASY
2
ctrl6
+ +
+ +
+ +
e m p t y
The retracts are extended and retracted when you oper-
ate the switch “SW 2”. You may need to adjust the travel
of the transmitter control, and perhaps reverse that
channel by setting a negative prefi x for servo travel.
F3A models fl y fairly fast, and respond very “solidly” to
corrective movements of the servos. However, in com-
petition fl ying it is vital that all abrupt control movements
and corrections should be kept to a minimum, as the
judges will invariably notice any lack of smoothness and
dock a few points, so it is advisable to set exponential
control characteristics on the stick functions.
Move to the ...
»D/R Expo« menu. (page 66)
Exponential values of 30% on aileron, elevator
and rudder have proved to be a good starting point, and
you can set them in the right-hand column of this menu.
These values provide smooth, well-defi ned control of
SEL SEL
typ fro to
M1
M2
M3 c1 5
?? ??
Tr
c1 el Tr
3I
3I
The mixers are activated using one and the same
external switch, e. g. switch No. “3”, which therefore has
to be assigned to
both mixers, with the same direction
of effect.
Move to
using the rotary cylinder, press ENTER
or the rotary cylinder to move to the mixer inputs on
the second screen page, and set the appropriate mixer
ratios. In both cases the mixer neutral point should be
left at the centre position of the Ch 1 stick travel.
For this reason you should now select the
ASY fi eld,
move the Ch 1 stick to the Idle range, and enter the
following values:
MIX 1:
-60% … -80% and
MIX 2: -5% … -10%.
Example of MIX 1:
MIX 1 c1 5
trv
– 66% +
0%
0% offs
SYM ASY
This completes the basic set-up for a typical F3A model.
Correcting model-specifi c errors
It is an unfortunate fact of life that even very carefully
built models exhibit minute faults and inaccuracies which
produce unwanted deviations when the model is fl ying;
the typical F3A model. Many experts use higher values;
even up to +60% exponential.
SEL SEL
100%
100%
100%
33%
33%
33%
aile
elev
rudd
DUAL EXPO
+
+
+
Since F3A models generally have two aileron servos, it
has proved useful to defl ect both ailerons
slightly “up” for
the landing. In most cases this causes the model to fl y a
little more slowly and with a more stable attitude on the
landing approach.
To achieve this you will need to program mixers in the ...
»free mixer« menu. (section starting on page 89)
Both ailerons are usually required to defl ect “up” as a
landing aid, in parallel with the movement of the throttle
stick, but only from the half-throttle setting in the direc-
tion of idle. From that point on, the further the stick is
moved towards the idle position, the more the ailerons
defl ect up. The reverse occurs when you open the
throttle: the ailerons are returned to neutral to avoid the
model suddenly ballooning up.
A little down-elevator must usually be mixed in to ensure
that the aeroplane does not climb when the ailerons /
fl aps are extended.
To meet these requirements you need the two mixers
shown in the illustration below.