Boris Murmann, Bernhard Boser, Digitally Assisted Pipeline ADCs: Theory and Implementation, Kluwer Academic Publishers, Boston, 2004, ISBN 1-4020-7839-0. Hardcover, pp 155, plus XX

A power shift transmission control system includes a modulation control valve connected for regulating the pressure engagement of forward and reverse direction-friction devices and including a pressure-regulating spring which is adjusted by means of a pressure boost piston. A feedback conduit conveys fluid pressure from the forward or reverse direction-friction device to the chamber, and the rate at which this pressure is conveyed to the chamber is controlled by an orifice-selector valve which is operative to selectively place various sized orifices in the feedback conduit in response to the speed-selector valve being placed in the various speed positions.