This is the "standard pulse servo mode" used by all hobby analog servos. Most servos are rotary actuators although other types are available. Long runs of mechanical and hydraulic connections were replaced with wires and electric servos. Typical servos can give a rotary (angular) or linear output. Small servos may use power transistors. Hydraulic servos were later used to position guns. Some were hydraulic, while others used electrical servos. Some players even had twin laser reading circuits to eliminate excessive servos. Two electric servos power the canards to steer the missile (except AIM-9X). These errors are detected, commutated, amplified, and used to control the antenna-positioning servos. The coating and servos are built on a metal skull. Escapements were disappearing from radio control, in favour of servos, by the early 1970s. Standard servos can then be used in the model. This motion was smoothed by an oil-filled dashpot, one for each of the three servos. These need to allow settling time for the servos.