Insulated mounting strips

Early electronic circuits featured point-to-point wiring, in which component leads are terminated without a printed circuit board. One characteristic of point-to-point assembly is the randomness of terminations. Often, manufacturers used any spare conductor as a terminal, including unused tube pins or socket connections, bent pieces of chassis, or even the flying midair leads of other components.

For important connections, however, an insulated mounting strip was the best option. Mounting strips gave sensitive or high-power connections a reliable, standardized termination point. There are various configurations, but mounting strips typically contain one or more tinned lugs that are insulated from one another and from a screw-down chassis mount. The lugs are spacious enough to terminate multiple wires or components, and the insulation is usually a heat-resistant phenolic material.