Model Helicopters - GRAUPNER mx-24s Programming Manual

Model helicopters

The continued development of model helicopters and
helicopter components, such as gyros, speed gover-
nors, rotor blades etc., has led to the current positi-
on where helicopters are capable of sophisticated 3-
D aerobatics. In contrast, the beginner to helicopter
fl ying needs a simple set-up so that he can quickly
get started on the initial stages of hovering practice,
and then gradually work up to more complex models
which exploit all the options provided by the
mx
The helicopter program of the -24s can cope with
all current model helicopters equipped with 1 ... 4 ser-
vos for collective pitch control.
Each model memory can include seven fl ight phases
plus auto-rotation (see the »Transmitter control ad-
just«, »Phase settings« and »Phase assignment«
menus).
As with fi xed-wing model aircraft, the standard timers
are included in the basic display, and additional timers
and a lap counter with stopwatch function can be se-
lected separately for each fl ight phase (»Timers (ge-
neral)« and »Flight phase timers«).
Apart from the collective pitch / throttle trim, all the
digital trims can optionally be stored separately for
each fl ight phase ("phase" setting) or "globally", i. e.
applying to all fl ight phases. The digital C1 trim provi-
des a simple means of returning to a pre-set idle set-
ting.
42 Model helicopters
The transmitter control assignment for inputs 5 ... 8
can also be set separately for each fl ight phase (see
the »Transmitter control adjust« menu).
During the test-fl ying phase the copy fl ight phase
function can be particularly helpful (see the »Copy /
Erase« menu).
"Dual Rate" and "Exponential" are available for roll,
pitch-axis (elevator) and tail rotor, and they can be
mx
-24s.
coupled together and programmed to provide two set-
tings in each fl ight phase.
It is possible to set up eight freely assignable line-
ar mixers, and four curve mixers can be programmed
and switched on and off separately in each fl ight pha-
se in the »MIX active in phase« menu. Four dual mi-
xers are also available.
Eight-point curves are provided in the »Helicopter
mixers« menu for the collective pitch, throttle and tail
rotor mixers, variable separately for each fl ight phase,
generating non-linear mixer characteristics. Two sepa-
rate swashplate mixers are also provided for the roll
and pitch-axis functions. Independently of this feature,
the control curve for the Channel 1 stick can also be
defi ned using up to eight points, separately for each
fl ight phase. These advanced features are not nee-
ded by the beginner, who will usually start simply by
setting the hover point to coincide with the stick tra-
vel centre.
Collective
Pitch Curve
Swashplate
Rotation
Roll Throttle
Pitch-Axis Throttle
Channel 1 Throttle
Pre-programmed mixers in the »Helicopter mixers«
menu:
1. Collective pitch curve (with eight-point curve)
2. Channel 1
3. Channel 1
4. Tail rotor
5. Roll throttle
6. Roll tail rotor
7. Pitch-axis
8. Pitch-axis
9. Gyro suppression
10. Swashplate rotation
11. Swashplate limit
The "Throttle limit" function (Input 12 in the »Trans-
mitter control adjust« menu) provides an effecti-
ve means of starting the motor in any fl ight phase. By
default, transmitter control 9 – the right-hand side-
mounted proportional control – is assigned to input
12, and the position of this "throttle limiter" determi-
nes the maximum throttle servo position, i. e. the side-
mounted proportional control governs the motor over
the idle range. The programmed throttle curves only
take effect when the proportional control is moved to-
wards full-throttle.
i
Roll Tail Rotor
Pitch-Axis Tail Rotor
Channel 1 Tail Rotor
throttle (with eight-point curve)
tail rotor (with eight-point curve)
throttle (with eight-point curve)
throttle
tail rotor