Telebee Gyro How-to
using the Futaba 8U Super

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Connect the rudder servo to top connector. Make sure the plugs go in the right way. Click on the picture to the left to see what color wire should be on what side. Run one of the extension cables that came with the gyro from the middle connector marked 'To receiver 1-4' to the rudder channel on the receiver (ch.4). Next run the other extension cable from the bottom connector marked 'To receiver aux' to ch.5 on the receiver.
NOTE: If you have the old style case, then the connector on the gyro sensor box is used for factory programming only. Do not connect anything to it.
Mount the Gyro on the back plate behind the main shaft. Do NOT pay attention to the instructions for gyro orientation. As long as you have the orange sticker on top then you have it mounted in the right orientation. I mounted mine with the arrows pointing left/right and the cord coming out of the sensor box toward the back of the helicopter (click on photo at the left). The gyro comes with two pieces of foam tape that work really good. I put one strip on the bottom left edge and the other on the bottom right edge. If you need to replace the tape, you can use the CSM tape part # CMLG150
  Before we continue it helps to understand the characteristics of this gyro. You will notice that your rudder stick only moves the servo for the first 75% to the right and the first 25% to the left. The servo does not move when the stick is past these positions. Also the gain pot on the gyro sensor box does not work when you use the remote gain. It does not matter what position the pot is set to. The radio controlled gain takes priority. Another thing to remember is that all heading hold gyros have to initailize. This one takes about 9 seconds. Don't move the helicopter during the first 9 seconds after you turn it on. The gyro will let you know it's finished by moving the servo just a little bit one way then back. It will also turn on a red LED on the back of the gyro sensor box.
Common misconception of all heading hold gyros Another thing that a lot of people don't understand is that the rudder travel adjust (ATV's / EPA's) does not adjust how far the servo moves. You cannot use this to prevent linkage binding. This adjustment only effects how fast the tail moves (your pirouette rate).
radio setup Disconnect the rudder link from the servo. Turn on the radio and receiver. Wait 9 seconds for the gyro to initialize. It will move the rudder servo a little to let you know it's ready. Also you will notice a red LED light up in the back of the gyro sensor box.
zero center position In the radio go to the 'SUBTRM' menu and the rudder to 0 and gyro to 0.
trim step rate Go to 'TRIM' press the right arrow key until you get to TRM-RU and use the +- keys to set the value to 1.
set limits to 100% Go to 'ATV' menu and use the right arrow to select 'ATV-RU'. Hold the rudder stick to the left and set the value to 100%, hold the rudder stick to the right and set it to 100%. Go to 'ATV-GY' and make sure both sides are also set to 100%.
dual rates to 100% Go to D/R menu and set all channels to 100%.
set the gyro gain Go to GYRO in the Advanced menu and look under the word 'GYRO', if it does not say 'on' then press the + key to turn it on. Press the right arrow, then set the gain you want for Normal flight mode. I would start off around 85. Press the right arrow and you will see IDL1, set the gain value you want for flight mode 1. I would start with 15. Press the right arrow and use the +- keys to select SW-E. The concept is to use values below 50 and above 50 to not only choose between HH or Normal, but also to adjust the gain in each mode. For example if your value is 80, that would put the gyro in normal mode with 60% gain. If you set the other side to 20 then it would make the gyro operate in heading hold at 60% gain. The further from 50 (high or low) the higher the gain will be. Going above 50 tells the gyro to use standard rate mode and going below 50 tells the gyro to use heading hold mode.
set to normal mode While in Normal flight mode, move the rudder stick to the right, then back to center, if the servo does the same then you are in normal mode. If the servo moves to one direction but does not move back to center then you are in heading hold mode. If not, then reverse the values in the GYRO menu. In other words set normal mode to 15 and IDL1 to 85. Note: if you want to keep the values above 50 for standard rate, then another alternative is to go to the REVERS menu and select the gyro channel and make it opposite of whatever it is set to now.
servo direction Check the servo direction. Move the rudder stick to the right and watch the servo arm. It should move the servo clockwise which thereby should pull the rudder control link forward. This will make the nose of the helicopter rotate to the right (if you assembled the hub the right way). If not, then go to the rudder channel in the REVERS menu on your radio and change the direction.
gyro direction Rotate the helicopter so the nose goes to the left and watch the rudder servo. The servo needs to rotate clockwise. If not, then flip the reverse switch located on the back of the gyro sensor box.

With the rudder link disconnected from the servo. The first thing to do is make the link slide as free as possible. Adjust the guides to acheive the least resistance. I added a slight bent to the front section of the rod as you can see if you click on the photo to the left. I did this so as to stop the resistance the rod had on the first frame guide due to being pulled down to the servo. I also used a JR Ball link resizing tool to remove unecessary resistance from the ball links. Once you get the link as free from resistance as you can, turn on the radio and receiver. Wait 9 seconds for the gyro to initialize. It will move the rudder servo a little to let you know it's ready. Set the rudder servo arm so that it points a few degrees clockwise of straight up (pointed toward the front of the heli) with the rudder stick and rudder trim centered. The best position for tail centering is to adjust the rudder link so that you have 4.5mm between the pitch slider and the tail rotor casing with the collective stick centered up/down and left/right. Check that the front link is centered with the servo arm. If it's not, turn the link clockwise to move it toward the back or counter clockwise to move it forward. Once the center of the ball link matches with the center of the arm and you have the 4.5mm at the tail slider, then you can move to the next step.
  Hold the tail rotor stick full right and pull the control rod all the way forward. Note: The servo will only move during the first 75% of stick movement. This does not mean something is wrong, this is the way it was designed. Hold the link over the servo arm to see which hole it will align with and install the ball in that hole. Mine worked out to use the hole that is 9mm from the center. You want to use the one that is furthest from center that does not allow the servo to mechanically bind. After you mount the ball, confirm that it does not try to pull the link further than it can mechanically go either right or left. Now you can snap the link on the ball.
Notes about this radio setup The above configuration lets the flight mode switch select heading hold while in flight mode 1 or 2 and standard rate while in normal mode. It also allows the gain for each mode to be set in the GYRO menu. Gain values are 0-50 for heading hold and 50-100 for standard rate. The further from 50, the higher the gain.
Flight adjustments
with independent
normal/HH trims
Go to OFST-1 and turn it on. This will allow the trims to be independent between all flight modes. While on the bench you need to set the HH center. If as soon as the gyro enters HH mode, then the tail servo immediately starts drifting until it reaches the limit on one side or the other, this means the trim needs to be adjusted. If the servo moves slowly, it will only need a few clicks. So flip from normal to flight mode 1 and watch the rudder servo. If it moves, then while in flight mode 1, use the trim to stop it. Flip back to normal, then to HH, you want to get it set so that when you switch, the tail servo does not move. Note: This will get you close, if not perfect, for actual flying, but you should be aware that my experience has been that due to vibration or whatever in flight, that the center position is different. So when you flip the switch, the tail might drift. Just adjust the trim to stop the drift. Afterwards, you will see that on the bench, the tail will drift when going from normal to HH, but that's okay, since it will be right while flying.
The first time you hover you can set the trim for the normal rate mode. Just use the rudder trim since you don't have to be concerned about it interacting with the HH mode.

Gain settings:
For normal mode you want to increase the gain until you see the nose of the helicopter wag (oscillate back and forth), then back off the gain. That will be the highest you can set the gain. Do the same for HH.
NOTE: If you can't get a gain in normal mode that is close to 100% then you may have too much vibration or the servo arm is too long.

Symptom Cause
Gain values for Normal and HH are low. 1. The helicopter is out of balance. Vibration is the cause of low gain settings. Check the blades, check for bent main shaft, spindle shaft, tail shaft, out of balance tail blades, etc.
2. I found that a sticky clutch caused me to have to turn down my gain by 20%. Check the
engine/start shaft alignment and look for a broke shoe.
3. The electronic boards inside the sensor box could be vibrating. Use small rubber foam pieces inside to cushion the circuit boards.
4. The ball on the rudder servo arm is too far out.
HH doesn't hold good 1. The RPM's should be 1850 to 1950 for 3D flight. It's also important that your engine is running good. If your engine loads up a lot then you won't be able to keep a consistent RPM.