The many interests of a modern techno-geek

This is how I set up the G401B Gyro with my DS290G tail servo.  Good information on this gyro can be found here.  It is basically a Piezo clone of the Futaba GY401 Gyro.  One note I have: Don’t buy this from ChaosRC, they are not a reliable seller. Try http://www.cnchelicopter.com

Anyhow, here is how I got it set up:

1. Get servo horn mounted 90 degrees with tail pitch slider perfectly centered. If you are using a digital servo, set the DELAY screw on the gyro to Zero, if analog start with it at 50

2. Start up the heli in HH mode and then switch to rate mode. (try to have the motor disconnected here) – Make sure your Travel adjust for the Rudder servo is 100% and the Dual rates for the rudder is 100% and I did this with Zero expo as well.

3. Move the rudder L and R and make sure the tail is moving the correct way (Depends on the helicopter – check the manual) – if it is not reverse the servo.

4. put it back into HH mode and check to make sure when you manually push the tail, the gyro is compensating correctly, if it is not, flip the reverse switch on the gyro.

5. Okay, now go back to rate mode (gain under 50%) and move the stick all the way to the left and right, change the LIMIT screw on the gyro until left and right rudder are fully moving the tail slider without any servo binding or buzzing.  If the tail servo buzzes as if it is fighting to keep pushing the tail, lower the limit.

6. Set gyro gain to something near 70 to start off with, if you lift off and go outside and hover.  While flying, if the tail wags, lower the gain.  If it doesn’t wag, increase the gain until it wags and then back off until it stops wagging.  I run about 66.5% gain in my TX and the gyro takes Idle up throttle punches like a champ.  From here all I had to do was restart the helicopter in HH mode and it worked like a CHARM.   However, I am using the DS290G tail servo and since yours might be on the analog setting please continue to the next step.

7. After you get the gain where the tail holds but does not wag, now it is time to make sure your piros are not bouncing.  Do a quick piro clockwise and counter clockwise.  Check to see if the tail bounces after doing either direction piro, to eliminate the bounce, try increasing or decreasing your delay.   If it makes the bounce worse in either direction, move the the delay screw the opposite way. You have to get the delay to balance between bouncing on clockwise and counter clockwise piro’s.  Basically, the delay is trying to match the gyro command speed to the servo’s speed.

Sometimes I get a bit of bounce on piros anyhow, I haven’t perfected it but I don’t get bad bounces ever, and most bounces I get are small and don’t effect my flight.

Good luck