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Detail program description - Helicopter mixer
vertical axis, observe the following:
The controls should have as little friction and 
"play" as possible.
There should be no "spring" in the control linkage.
Use a strong and comparably fast servo. 

When the gyro sensor detects a model rotation, the 
faster its response – a corresponding corrective 
change to tail rotor thrust – takes effect, the further 
the gyro gain adjuster can be moved without causing 
the tail of the model to start oscillating, and the better 
the model's stability about its vertical axis. If the 
response is slower, there is a risk that the model's tail 
will start to oscillate even at low gyro gain settings. 
Here, further reductions to gyro gain will need to be 
made to eliminate the oscillation.
If the model is fl ying forward at high speed or 
hovering in a powerful headwind, the net result of the 
stabilizing effect of the vertical fi n combined with the 
gyro may also lead to an overreaction that once again 
manifests itself through tail oscillation. To achieve 
optimum gyro stabilization under all conditions, you 
can make use of the option to adjust gyro gain from 
the transmitter using a transmitter control assigned to 
input "7", in connection with gyro suppression and/or 
the two settings on the Gyro NEJ-120 BB. 
Further notes on gyros with confi gurable multilevel 
gyro gain (e.g. NEJ-120 BB)
Since you cannot specify the gyro gain from the 
transmitter proportionally via the transmitter control, 
the gyro's own control 1 must be used to set the 
(weaker) gyro gain (e.g. for aerobatics) and control 
2 the stronger gyro gain (e.g. for hovered fl ight). 
Even though a proportional control is used for control 
function 7, only a switch-over between these two 
values takes place and the setting is therefore not 
proportional. 
You should therefore advance control 2 to the point 
where the model is on the brink of oscillating when 
hovering in calm conditions, and advance control 1 to 
SEL
Roll
Tail rot.
Nick
Throttle
0%
0%
Nick
Tail rot.
0%
Gyro suppression
0%
Gyro offset
0%
Normal
Based on these fl ight-phase specifi c (offset) settings, 
gyro gain can also be infi nitely varied by a transmitter 
control assigned in the "Gyr7" line of the »Control 
adjust« menu,
 page 116.
 Swashplate rotation
SEL
Nick
Throttle
0%
0%
Nick
Tail rot.
0%
Gyro suppression
0%
Swashplate rotation
Gyro offset
Normal
Some rotor head control systems make it necessary 
to incline the swashplate in a different direction from 
the intended inclination of the rotor plane when 
a cyclic control command is given. If your model 
features a four-bladed main rotor, for example, you 
may need to use this menu to set up a software-
driven 45° rotation of the control linkage to the right, 
so that the pushrods from the swashplate to the 
rotor head can be set exactly vertical, ensuring that 
the blade control system works correctly, without 
unwanted differential effects. This eliminates the need 
to make mechanical changes to the control linkages. 
Negative angles equate to a virtual rotation of the 
rotor head to the left; positive angles a virtual rotation 
to the right.
the point where the model does not oscillate with its 
tail even when fl ying at maximum speed into a strong 
headwind. Depending on the state of the weather 
and the fl ight program planned, you can also switch 
over the gyro gain from the transmitter – also with 
gyro suppression dependent on tail rotor defl ection if 
required.
  Gyro offset
Important notice:
The value of this option is identical to the offset 
value set in the "Gyr7" line of the »Control 
adjust« menu, page 116. For this reason, any 
changes made always affect the other menu 
directly – and vice versa.
Most of the latest gyro systems not only feature 
infi nitely variable proportional gyro gain setting, but 
also offer a choice of two separate types of gain 
mode on the transmitter. 
If the gyro in use has at least one of these features 
then this alternative offset setting provides an 
opportunity to preset both "normal" gyro gain as well 
as, as appropriate, to specify a "heading-lock mode" 
whereby, even within this pre-selection, gyro gain can 
be reduced by a particular gain type for normal, slow 
fl ight with maximum fl ight stabilization, fast circuit 
fl ights and aerobatics. 
To proceed as described above, use fl ight phase 
switching to enter different settings on the "Gyro 
offset" line. Values between -125 % and +125 % are 
possible: