GRAUPNER mx-20 Hott, Programming Manual

Page: 168 / 296

168 Detail program description - Control adjust
per fl ight phase) by up to 6 points, termed "reference
points", placed at any point along the joystick travel.
The reference points are defi ned, adjusted and erased
in the usual way, as explained in the previous section on
the collective pitch curve. Start by defi ning the throttle
curve with three points, namely the points "L" and "H"
at the extremes, plus the Point "1" still to be set in the
control center in order to match the motor power curve
to the collective pitch curve. Helicopter with carburetor or electric drive system
with speed CONTROLLER
This setting relates only to the control curve of the
throttle servo or the speed controller .
Setting the throttle curve to suit a helicopter equipped
with a speed
governor is discussed in the following
section.
As with the confi guration of the collective pitch curve
(see previous page), the throttle curve can also be
defi ned by up to 6 points.
In each case, set the control curve so that when the •
throttle/collective pitch stick is in its end position,
the carburetor is fully open or the controller of an
electrically-powered helicopter is set to maximum
(except for auto-rotation fl ight, see page 178).
For the hover point, which is normally at the control
•
center, the carburetor setting or power control for the
speed controller must be matched to the collective
pitch curve so that the correct system rotational
speed is obtained.
At the minimum position of the throttle/collective
•
pitch stick, the throttle curve must fi rst be confi gured
so that a glow motor runs at a speed considerably
higher than idle speed and the clutch is fi rmly
engaged.
The starting and stopping of the motor – whether
glow or electric – always takes place using the
throttle limiter (see below) within the respective
fl ight phase.
This makes it unnecessary to program the two fl ight
phases that may be familiar to you from using other
remote control systems – namely "with idle-up" and
"without idle-up", and with the associated "waste" of a
fl ight phase for this purpose – since the
mx-20
HoTT
program offers a much more fl exible approach to fi ne-
tuning and optimizing increases to system rotational
speed below the hover point than the "idle-up" approach
taken by older
mc
radio control units.
Ensure that the throttle limiter is closed before you start
the carburetor motor, i. e. so that the carburetor can
be adjusted within the idle range only by using the idle
trim. Ensure that you follow the safety instructions on
page 177 at all times. If the throttle is set too high when
switching on the transmitter, you will receive audible and
visible warnings!
STARLET
#02
2:22h
Stop
Flug
K78
0:00
0:00
5.5V
5.2V 99%
«Nor mal »
M
Throttle
too
high!
The following three graphs show (typical) 3-point throttle
curves for various fl ight phases, such as hovering
aerobatics and 3D fl ight.
Sample throttle curves for various fl ight phases:
+100% +100% +100%
-100% -100% -100%
Output Output Output
2 3 4 5 1 2 3 4 5 1 2 3 4 5 1
Control travel Control travel Control travel
Hover Aerobatics 3D
Notes on using the "throttle limit" function:
You should make use of the throttle limit function as •
a general rule (menu " Control adjust " , page 104).
This will fully isolate the throttle servo from the
throttle curve with the throttle limit proportional rotary