Using an analog microamperimeter this circuit has a phototransistor adapted to the wheel as a sensor. The circuit is from American documentation from the 1980s, but the components are common today.
This circuit was obtained from Popular Electronics from March 1967. The transistor used is from...
The purpose of this circuit is to control the high and low light of a car, detecting when a...
This circuit triggers three incandescent light bulbs following the audio signal applied to its...