Originally posted by MinnFlyer
Not true. Both servos will turn the same way. You must hook your push rods to the opposite side of each servo to get the desired opposite movement. If you need to reverse the direction of the servos (as for elevators) you need a reversing Y Cord (if you don't have a computer radio)
Also not true. You can get differential from a single servo by rotating the 6-arm wheel 30 degrees (45 degrees for a 4-arm wheel) and connecting to the two parallel arms (See Pic).
MinnFlyer you may be correct on the Y-Harness. I will have to check that tonight when I get home.
And I should have been more clear on the differential. I was tankling aobut mixing it in the radio and tying it to a switch so that you can adjust it in flight. I was actually trying to figure out how to do it when I saw this post.