Variable resistor with light indication - light inside slider head varying in intensity with resistance caused by slider movement

摘要

The variable resistor consists of a rectangular housing with a slit along its top surface to allow the slider arm to move along. The slider head contains a lamp connected by wires down through the slider arm to contacts on the part of the slider inside the housing. The resistance material is fixed to the base of the housing and lies parallel to the fixed contact paths over which the slider contacts move. As the slider is moved along, the resistance varies and so does the current through the lamp. The lamp intensity therefore gives an indication to the resistance value. The arrangement is particularly useful in audio replay systems.