Jerry Nelsons article is a good discussion but remember he is a manufacture and he is motivated to inform as well as interest you in his products. For 90% of the flying out there the setup he shows is way overkill. It realy is a simple set up with stock non speacilized hardware. Use a BB servo to handle the load, your standard servo wheel/Arm string/fishing line etc and have the attach points of the rudder horn behind the hindge line. adjust and snug up the lines and you will see that when you move the rudder off center one line will tend to go slack this isn't a problem since the airloads will keep the otherline taught and you have positive control. I have used this simpler system for at least a dozen planes some that exceed 100MPH so I know the system works without all the fancy hardware.
Sparky