Can someone please explain the HH futaba 240 gyro

[Shark Attack]

I have been flying before we even had gyro's. for the life of me I can not understand how this heading hold works.

I hovered my t rex the other day and I have little tail rotor control. the tail stays in place, but it takes full stick movment to get the tail to move. If i reduce the sensitivity down to a point where I have TR control, the tail is all over the place as if no gyro is in the heli.

When the heli is sitting on the bench and the gyro is on the TR servo moves real slow no matter how fast I move the stick...

What don't i get here??? I am using a 9c futaba radio, if it matters

[BarracudaHockey]

I'm guessing you set the end points on the rudder fairly low to prevent binding.

Set the end points to 100 and use the servo arm length to set the linkage throw. Run just enough gain to hold the tail well.

[Pla]

On a HH gyro the stick only controls the rate of pyro/rotation.
The 401 has a limit pot that limits the travel of the servo. The 240 doesn't have it so you can only limit travel by using shorter servo arm.
Set the transmitter end points to 100% - this won't change how much the servo travels.

Set gain so that it holds the tail but doesn't hunt (too much gain and you'll see hunting, too little and it won't hold the tail).

[DavidH]

http://manuals.hobbico.com/fut/futm0809-manual.pdf

Adjust the gain to about the 60% point and start there. Gain is adjusted with the pot that is on the gyro.
Also the gyro can be set in AVCS mode or Normal( rate) mode by a dip switch on the gyro. Choose which mode you would like to use. The norm today is to use AVCS mode ( heading hold).

As mentioned the ATV's on the rudder channel in your transmitter is what controls the pirouette rate for the tail. Start with 100% ATV in each direction for channel 4 on your transmitter.

From the GY 240 instructions
<One-Point Advice>
The gyro sensitivity also changes with the length of the servo
horn.
If the sensitivity is too low, lengthen the servo horn. Conversely,
when hunting does not stop, shorten the servo horn.

<Other Precautions>
• To improve the tail control characteristic, a delay function is
added to the rudder control signal from the transmitter. When
this signal is passed through the gyro, movement of the servo
is slower than the transmitter rudder operation. This is
normal.
• When the fuselage is static, the servo may move a little. This
is normal and occurs because the gyro sensitivity is set to a higher value


David

[Shark Attack]

yep, you nailed it. i have my ATV cut way back to avoid end point binding. Ill try it, THANKS!
Kyle