GRAUPNER mx-20 Hott Programming Manual page 277

After test-fl ying and trimming of the model, we
recommend reducing the trim travel for the elevator and
ailerons The model has signifi cantly less of a reaction
to a movement of the trim lever. "Overtrimming" can
be avoided, because with full trim travel, under certain
circumstances, the movement by just one trimming
step can have too strong of an effect: Therefore, the
model which previously pulled slightly to the left, hangs
somewhat to the right after the trimming. For this
purpose, switch to the menu ...
"Joystick setting"
... and reduce the number of trimming steps accordingly
in the "St" column:
Ch.1 GL 4 0.0s
Aile GL 2
0.0s
Elev GL 2 0.0s
Rudd GL 2 0.0s
Tr St
It may also be necessary to assign a corresponding
operating element to a specifi c input for the activation
of the retractable landing gear and the mixer movement
through the menu ...
"Control adjust"
... such as one of the ON/OFF switches to the Input 6
for the landing gear and one of the proportional rotary
controls, e.g. CTRL 7, to the Input 7. However, since
it involves fl ight-phase independent settings, leave the
standard default "GL" in the "Type" column:
Input 5
Input 6
Input 7
Input 8
The control travel of the operating elements must be
adapted and can also be reversed with a negative travel
setting.
(page 92) Notice:
A delay time for the extension and retraction can be
specifi ed for the retractable landing gear, which does not
work, however, for the landing gear servo C 713 MG,
0.0s
Order No. 3887.
0.0s
F3A models fl y comparatively fast and thus react
0.0s
"harshly" to the control movements of the servos.
0.0s
However, since small control movements and
corrections are not optically perceptible, because this
+
time
results in inevitable point deductions in competition, we
recommend setting an exponential control characteristic
of the joystick. For this purpose, switch to the menu ...
" Dual Rate / Expo "
Experience has shown positive results with values of
(page 96)
approx. + 30 % on the ailerons, elevator and rudders,
which you set in the right column with the arrow keys.
In order to be able to control the F3A model to run
smoothly and cleanly:
GL ––– 0%
GL 3 0%
GL Ct7 0%
GL ––– 0%
typ offset
(page 108)
Ail ––– +33%
Ele ––– +33%
Rud ––– +33%
EXPO
normal
SEL
(Some experts even use up to a +60 % exponential
degree.)
Since (some) combustion motors do not react linearly to
movements of the throttle joystick, through the menu ...
"Channel 1 curve"
... a "bowed" or, in other words, non-linear throttle
curve can be set. Four-cycle motors with Roots pumps,
in particular, such as OS Max FS 120, require a steep
ascension of the curve in the lower speed range.
However, the corresponding values must be adapted.
The C1 control curve for the motor could appear as
follows:
C1 Cur ve
Cur ve on
Input –50%
Output 0%
Point 1 0%
nor mal
Only three interpolation points, "L" at -100 %, "H" at
+100 % and "1" at -50 % give the control travel the
rounded curve above.
Detail program description - Control adjust
(page 116)
277