Cruise Control Systems: Operation: Transducer

Transducer has two primary functions. First, it is a vacuum switch which, when engaged by driver, supplys vacuum to a "tee" fitting. Second, it meters a small variable quantity of air to the "tee" fitting where it blends with vacuum, thus providing servo unit with controlled vacuum which will maintain the selected speed. Transducer is driven by a cable from the speedometer gear in transmission and mixes the controlled vacuum supply according to changes it senses in car speed. Transducer also drives a second cable to speedometer.