A circuit to detect a movement of an object has a calibration time period that ends when peak detectors in the circuit stop updating for a predetermined amount of time. The mounting interface between the ends of the axles and the sideframe pedestals allows lateral rocking motion of the sideframes in the manner of a swing motion truck. The quick page message indicates that a communications request has been received, and that the receiving communication terminals should process a highly encoded full paging channel over which more detailed, full page messages are transmitted during the next full paging slot. A seal is disposed in an admission orifice, for largely filling in an air gap between the centrifugal fan wheel and the inner surface of the fan housing.