Bob, I am impressed with your ability to track down and resolve this problem. I was especially amused at your early solution, though. The idea of using a hand vacuum pump to keep the truck going at idle was great. The things we will do to keep moving.
"It appeared the steel gear and shaft were becoming magnetized by the wiping action from the camshaft and caused the Hall Effect sensor to get false readings"
Bob, these problems occurs with Hall Effect sensors. When I had done some experiments with Hall Effect sensors, I found that any magnetic field near to the Sensor will be interpreted as signal. This will lead to the malfunction of system, where sensor o/p is served as the input to the system. I had faced similar problem in Brushless DC motor drive, where Hall Effect sensors are using to drive the circuits.
Using wireless chips and accessories, engineers can now extract data from the unlikeliest of places -- pumps, motors, bridges, conveyors, refineries, cooling towers, parking garages, down-hole drills and just about anything else that can benefit from monitoring.
With strong marketplace demand for qualified engineers across the board that currently outstrips the available supply, there may never be a better time for engineers and project managers to advance their careers and salaries. Whether those moves are successful in the short-term and long-term is likely to depend on how the transition from one job to the next is handled.
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