Porcelain coated steel printed wiring boards

The technology of porcelain coated steel substrate; is seen as a vehicle for extending the scope of hybrid circuitry from its present use in individual function circuits to encompassing an entire system. There is a specific discussion of the option of replacing a circuit in which hybrids are mounted on an epoxy-g1ass mother board with a single porcelain coated steel substrate which does the whole job. Considered in this article are the history of the porcelain steel technology, the method of fabrication of porcelain steel substrates, their characteristics, limitations, and cost.