Passive component plate, type A3, for Sargrove sprayed-circuit radio receiver, made by John Sargrove, Walton-on-Thames, Surrey, England, 1936-1948.

John Sargrove was a pioneer of Electronic Circuit Making Equipment (ECME), in order to automate the process of making radios. ECME could automatically produce complete radio circuit panels ready for assembly, at a rate of three per minute. A pre-moulded Bakelite panel was grit blasted, sprayed with metal and graphite, milled, lacquered and tested, emerging 20 seconds later for final assembly. The panels then only required a few components such as valves to be inserted by hand, and the completed assembly was fitted into a cabinet. This is an example of a component plate made by Sargrove between 1936 and 1948. His idea was never taken up generally, partly because it was seen as a threat to jobs, but represents the first modern approach to automatic operation in electronic manufacture.