signaled to commence destroking the term destroking is used in the vernacular to define the change in a piston type variable displacement pump when it goes from full stroke to partial stroke in other words the displacement of the pump decreases in terms of fluid output however it increases in terms of pressure generation this is accomplished through the mechanisms of the dual pressure compensator pressure in the first chamber 120 has increased with the pressure generated by the pf pump this pressure increase was communicated between conduit means 24 and the dual pressure compensator 50 by conduit means 42 see fig1 a portion of the first chamber 39 s boundry is the first end 98 of the spool 80 thus spool 80 is biased against the biasing assembly 72 by any significant pressure in the first chamber 120 pressure in the second chamber 122 has also been increasing the second chamber 122 gets a fluid pressure signal from conduit means 28 through conduit means 44 to reiterate point b represents the pressure at which the pressure in the first chamber 120 and point in the second chamber 122 have combined to override the pressure on spool 80 imposed by biasing assembly 72 this forces the piston land 104 to slide past the first outlet port 68 this action then allows passage of fluid from the second inlet port 66 to the first outlet port 68 which communicates with the actuator 58 of the pv 14 the actuator of the pv will destroke the pump.