Bob writes – “The oxygen sensor simulator as built on a protoboard. Note the cigarette lighter plug used for power source. The adjustment knob is at the left, and the switch is on the right. The red indicator LED is in the middle. Only use red, because the voltage drop of the LED is part of the circuit!”
…good project for the drag racers (from the Q&A)
“I do racing on the weekends with my street car. Will this project help me tune the car to different conditions? A: If you do drag racing, yes. The races are short enough you can set a mixture and it will hold long enough. Each time you start the car it will go to the mixture you set. Other forms of racing take too long, and the mixture will creep towards very rich, you’d have to adjust the knob while driving.” [via] – Link.