A gap sub assembly can be used to form an electrical isolation in a drill string, across which a voltage is applied to generate a carrier signal for an electromagnetic telemetry system. A cross sectional area of a gas passage changes in a direction in which the gas passage groove extends, while each of an opening width of the gas passage groove and a depth of the gas passage groove remains substantially constant. The remotely accessible server responsively generates an electronic redemption code and a corresponding electronic sales code. The turret further comprises a turret controller which uses feedback control to control rotation of the turret relative to the vehicle. The fiberboard bedding can be hogged or chopped to provide a soft nesting area for the animal and also keep the animal dry. In some embodiments, multiple groups of page buffers may be activated simultaneously to access multiple sectors, while page buffer groups for unselected sectors are deactivated.