The preferred method in the United States uses the main-sheet balance gear, in which the boom is connected with the tiller in such a manner that, when it swings out with a pressure of wind, the rudder is automatically pulled round sufficiently to keep the yacht in its course. This will usually involve some sort of return spring so that the mechanism is responsive to the wind. This apparatus is particularly efficient in sailing before the wind. More modern, computer-based RC transmitters often have mixing circuitry integral to their design, that can "mix" the sheet-balancing, operated with a sail control servo, internally in the transmitter's computerized encoder unit, with the rudder control.