Using the JR 9303 and the Futaba 611 Gyro

Personally, I leave the gyro in AVCS mode (heading hold) all the time with a gain of 35%. This has been a very good, very simple way to do it on all models, any size, from beginner to expert. Higher gain settings usually result in failures of the tail drive system and excess current draw and don't add to the ability of the gyro to hold the tail.

We must allow you to put the gyro in Normal (rate) mode so you can adjust the length of the tail rotor control rod and make small changes in the gain settings if it's needed.

Since we are not going to be changing the gain or mode automatically when we go into stunt mode, there is no need to use the Auto Mode. We want to simply flip a switch in order to toggle between AVCS and Normal mode and have the ability to change the gain from the transmitter. If at some time in the future you want to use the Auto feature, feel free. This information should help you understand the workings of your radio and the gyro.

Pay special attention to steps 6 and 18 . Step 6 is the one that trips most people up.

1. Turn on the transmitter and press LIST.
2. Go to TRVL ADJ. and set RUDD to 100% on both sides. Now set AUX2 to +100% on the left side and -100% on the right side.
3. Press LIST
4. Go to REV SW. and make sure the AUX2 is NORM not REV. (Now the channels we are concerned with are in the default settings.)
5. Press LIST
6. Go to GYRO SENS. If it doesn't say RUDD D/R, press the jog wheel and change it until it does. Set Pos. 0 to 0%. Set Pos. 1 to 100%
7. Press LIST
8. Go to MONITOR. Observe AUX2 while you toggle the RUDD.D/R switch on the top right of your transmitter. The mark should go from one side to the other. If it does, continue to the next step. If it doesn't, turn off the transmitter. While holding the enter button down, turn on the transmitter.
9. Go to DeviceSEL. Scroll to AUX2 and press the wheel. It should present a list of options. Select AUX2 SW and press the wheel. Now check using the MONITOR screen again. If it still doesn't work, I would suggest a data reset on the model and start over.
10. Power off the transmitter and receiver if it is on.
11. Make sure the rudder servo with the blue connector is plugged into the SX port on the gyro controller..
12. Make sure the gyro sensor is plugged into the GYRO port on gyro controller.
13. Make sure the RX 1-4 wire with the black connector is plugged into the RUDDER channel on the receiver.
14. Make sure the RX.AUX wire with the red connector is plugged into the AUX2 channel on the receiver.
15. Power on the transmitter, then the receiver. Be careful not to disturb the sensor until the "Hello" message on the gyro is replaced with the status message. Press the FUNC on the gyro controller until you see MODE. Make sure it is in CMT mode. Press the FUNC + four more times to return to the gain/mode screen...or just turn off the receiver and then on again.
16. Press LIST on the transmitter
17. Select GYRO SENS. Observe the display on the gyro controller. With the RUDD D/R switch in the down or forward position, adjust POS. 0 until the gyro controller reads G36N4.8v where G= gain, 36=gain value, N=Normal mode and 4.8v= voltage to the receiver. At this point, the Pos. 0 value on the transmitter should be about 30%. Now flip the RUDD D/R switch and adjust Pos. 1 until the gyro reads G36A4.8V where A=Heading Hold mode (AVCS).
18. If you see a black dot instead of the A or N, it simply means the servo/rudder channel is off center either because you're moving the rudder stick or you have bumped the rudder trim. Make sure the rudder trim is centered or flip the RUDD D/R switch quickly three times. You should not have to mess with trims.
19. Put the gyro in Normal mode using the RUDD D/R switch. At this point, the servo is in neutral position. The servo arm should be exactly square to the control rod. If it is not, change it until it is. drill a new hole if you have to.
20. Adjust the length of the control rod so that you think it will hover without rudder input. This is usually a point where, it the tail blades, when folded in the same direction, have about a 1 inch gap between the ends.
21. Check to make sure that when you move the rudder stick to the right, the control rod moves forward. This is always true on models that have the main blades turning clockwise when observed from above.
22. Make sure when you move the nose of the model to the left, the control rod moves forward. If not, you need to reverse the direction of the gyro. Refer to the manual.
23. Do a preliminary end point adjustment as described on page 20 of the 611 gyro manual.
24. Shut it all off, fuel it up.
25. Start it up, set it on a smooth surface and step back a safe distance.
26. Get it light on the skids. If it looks like it's not going to spin around, go ahead and lift it into a hover in normal mode. If you have to hold right rudder to keep it from turning, set it down and shorten the t/r control rod. If you have to hold left, lengthen the rod. Do this until the model does not yaw when you switch from heading hold to normal mode.
27. Now do the final end point adjustment on the t/r as described on page 20 of the 611 manual. Be sure to do this step after adjusting the control rod to the correct length.
28. Set your fail safe settings to hold all channels except throttle, which should go to idle.

Copyright © 2010 Ron Lund, RONLUND.COM and Ron's Heliproz South All rights reserved