A
dynamometer readout (42, 46) and method is disclosed for obtaining
dynamometer information (110) related to pumpjacks (10). For this purpose, a change of pivotal direction of the walking beam (18) may be detected by processor (82) utilizing an
encoder component (60) with spaced slots (64) therein and
light signal devices (68, 70, 72, 74) positioned to have a spacing different from that of the spacing of the slots (64).
Software techniques filter out effects of stray mechanical vibrations. An
infrared transceiver (46, 50, 100) of a preferred embodiment includes a
radio frequency carrier generator (90) and modulator (88) that produces an
infrared signal receivable by a low cost
consumer radio receiver. The
radio frequency modulation technique for
infrared signals (96) and related filtering (98, 102, 104) condition formatted infrared signals for utilization in
daylight and through a car window for drive-by downloading of data to second computer (108). A sensor (163) may be substituted for the
encoder. A sensor (163) may include a moveable light
interrupter, such as a ball (160) or a bubble (260), moveably disposed within the sensor. The sensor may also provide one or more apertures (180) for transmitting light through the apertures.