I am just setting up a Caliber 30 with a JR 8103 radio as well as a Futaba 401 Gyro with S9253 digital servo. For some reason I get full servo travel when I apply left rudder but only about 1/2 travel when I apply full right rudder.

The servo moves linearly as you move the rudder from neutral to around 50% right full travel. The servo does not move at all as the rudder moves from 50-100% right. If I plug the servo directly into the rudder channel, I get symmetric travel both left and right.

I'm new at this and would appreciate any help.

I had the same problem at first with a Venture. I think I ended up putting on a larger wheel on the servo. I then limited the travel in one direction to even them out.

I assume you have the travel pot on the Gyro at full?? Also, be sure your linkages are set up square.

This is normal, it will behave correctly when in the air.

Mike...

Actually, I've set up several of these gyros, and there is one other thing you might want to do first....

I noticed the gyro would do exactly what you mentioned if your revo mixing was enabled.

First, turn on the TX. Be sure to inhibit Revolutionary mixing (Don't just turn the rates to zero, you need to actually turn that function OFF). Set your rudder ATV's to their maximum limits (you'll adjust them in a minute, but for now turn them all the way up). Then, turn the 401 gyro to "heading hold OFF".


Now, turn on your RX.
Your gyro is in normal mode. At this point, your rudder trim lever should be centered. If the servo arm on the servo is not at 90 degrees, then you need to adjust it. The servo arm, and the tailrotor control arm should both be at 90 degrees. Ensure that the travel direction of the rudder stick and gyro are correct. For example, when you give a left rudder command, the tailrotor blades should move so that the leading edge of the blades moves opposite your command. So, if you give it a left command, the tailrotor blades will move right. (The leading edge, remember.) This is only true for a rotor head that moves clockwise.
Now, if your servo arm movement goes forward when you give a right rudder command, then, when you pick up the heli and move it quickly to the left, the servo arm should move in the same direction.

If this is all good, then you need to go ahead and switch the gyro to Heading Hold ON. The servo should move freely in both directions when you move the stick. If there is some slow movement of the arm, you can eliminate this by adding or subtracting some subtrim.

Now, for the ATV. At this point, the ATV is no longer an endpoint adjustment. It now regulates the speed at which the servo travels from one end to the next. Decrease the amount until you get a comfortable speed.

Hope this helps!

whats a fair price for a 401 brand new?

Don't pay more than $120 for it.

Here is the skinny on your Gyro. First make sure that all of the settings in your transmitter for the gyro is turned off, you have a heading hold type and requires no fancy inputs that are normall used for rate type gyros. Also as recommended by Futaba is turn on the Transmitter first and carefully turn on the Heli as to not to jar the craft while the gyro is "neutralizing" which is indicated by the flashing light. The craft cannot be moved until the light turns solid. If the light does not become solid the gyro is in rate mode. Yes, I know this can be confusing, but as a begginer you would be better off utilizing the heading hold feature. Highly recommend contacting your locall Hobby shop or other Heli pilots to help you on this one.