different horns to achieve that.
3) Fine-tune by adjusting
Servo Mid
such as to obtain 90° orientation of the servo horn.
4) Switch the gyro into rate mode and fly your heli at the desired head speed. Move the tail servo
and/or adjust the link length such that the tail is steady in hover. However, no need to overdo
here, minimizing the tail drift is sufficient, the goal is to avoid a too off mechanical setup.
Comment #1
: Strictly adhere to point (1).
Comment #2
: If your tail shows a small drift but you are too lazy to change the mechanical
setup, then you might think that it's a good idea to adjust
Servo Mid
a bit. This doesn't harm, but
in heading hold mode there is absolutely
NO
advantage of doing this, it's irrelvant.
Sometimes a more involved setup is of advantage. It needs some understanding and is hence
suggested only to experienced pilots. On a TRex450 there is a significant asymmetry in the tail
mechanics: The servo horn needs to turn much less for the pitch slider to move the same distance
to the left than to the right. Also, the maximum turn needed to push the tail slider to the left end
is only about half of that for moving it to the right end. This asymmetry can be accounted for by
not choosing 90° for the servo horn, but rather have it tilted towards the direction in which it has
to be turned less for the full pitch slider range (TRex450: tilted towards the main frame).
4. The Parameter Gain Input Function
The parameter
Gain Input Function
determines what the GA250-OW does with a signal at the
gain plug. The behavior of the gyro does in fact depend strongly on this setting. The
Gain Input
Function
parameter can be set to one of four values:
1) Gain Input Function = set gain & mode
This is the standard setting and most of you will want to choose this option. In this setting, the
gyro expects to see a signal at the gain plug (which implies that at start up the gyro will wait
during initialization until it detects a valid gain signal). The signal at the gain plug is interpreted
as the gyro's gain and sets the gyro into rate or heading hold mode, exactly as you know it for
commercial gyros. The relation of the gain signal and the gyro's gain and mode is as follows:
1920
μ
s (100%)
|
| gyro is in heading hold mode, 51.5% = lowest gain, 100% = largest gain
|
1532
μ
s (51.5%)
| undefined condition
1508
μ
s (48.5%)
|
| gyro is in rate mode, 48.5% = lowest gain, 0% = largest gain
|
1120
μ
s (0%)
The parameters
Gyro Mode
,
Rate Gain
and
PID Gain
are inactive, i.e., are overridden by what
the gain input signal says.
2) Gain Input Function = toggle mode
In this setting, the gyro expects to see a signal at the gain plug, as before, but this signal will
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