This is a quick and dirty setup routine for the CSM 540 Gyro. It is simple and shouldn't be mistaken as the only way to set the gyro up. Once you've got it working and understand it a little, reread the instruction manual and explore your own methods.

Futaba guys need to inhibit the gyro function now!!

First plug the rudder servo directly into the rudder channel in the receiver. Check the direction. Right rudder should pull the control rod to the front of the machine on most brands. Verify this by standing behind the model and watch the tail blades as you give it right rudder. The leading edge of the tail blades should move left

Remove all subtrim, stunt trim , revolution mix and any other mix that involves the rudder channel.
Center the trim tab on the rudder. For the CSM gyros a fairly long arm seems to work better. You can start at 15mm. Fit it so the arm is about 90 degrees to the rudder control rod. Adjust the length of the rod so the t/r bellcrank is 90 degrees to the rod. This might not be perfect, but it'll get you going.
 
Turn off the power to the model. Now go ahead and plug the aux-in into channel 5. Channel 7 has some issues that complicate things and we're trying to keep this simple.

Set the ATV on channel 5 to 60% on both sides. Set the ATV on channel 4 to 90% on both sides.

Turn everything off and unhook the linkage at the servo.

Turn on the transmitter. Turn on the receiver and immediately toggle the switch that controls channel 5 twice. This is usually the gear switch.

When you toggle the switch the rudder servo should go  full travel a couple times. This indicates it's in setup mode.

Move the rudder stick to the left and back to center. Toggle the channel 5 switch. You just told the gyro which way to go and moved to the next step in the setup.

Look at the super servo light on the gyro. Unless you have a JR Super Servo or a 9250, the light should be set to off. (there might be other servos that will use the high update rate, but these are the only ones I'm aware of at this time. (I've put a note from Bob Johnston about this at the end of this) Moving the rudder turns the light on and off. Once it's set the way it needs to be, toggle the channel 5 switch.

Now you're in the travel limit mode.  Hold your linkage over the ball on the servo arm. Move the rudder and watch the  tail pitch slider. Adjust it until it's close to binding, then toggle the  switch again. Now do the other direction. Toggle the switch again and you are finished. The rudder won't respond to the stick until you cycle the power on the gyro, so turn off the receiver.

Turn it back on.

Move the rudder to one side and let go. In heading hold, the slider should stay in place or drift slowly back to center. In normal mode it will return to center immediately. Put it in heading hold.
 
Now go hover the model. It will want to swing rather violently as it get light on the skids and before the tail blades gain the authority to control yaw. You'll anticipate this after a few times and it won't be a problem.
 
If the tail wags in a hover, lower the gain a couple points and try again. If it doesn't wag, raise the gain a couple points until it does, then back off a couple points.

If it holds somewhat, but not too well, put it in normal mode and adjust the control rod length until it doesn't yaw one way consistently. This is very important for good performance.
 
If the gyro doesn't work at this point, it's broke and needs to be serviced.

Look here for more info http://www.bobj.co.uk/CSM/csm.htm

An email from Bob Johnston

"Any Super or digital servo should be able to take a high frame rate but the ones I have personally tested {and these are the ones most likely to be used on the tail anyway are} 4000, 2700G (new and old type) 8700G, DS 8417 and the Futaba 9250.

The 8417 buzzes like crazy but this is ok and the servo does not get hot, if it gets hot it's from vibration in the model and not the high frame rate.

The new 8700G seems the best available option next to the old type 2700G, and in some ways might be a little better even."