Wednesday, January 23, 2008

Machines Make Radio

This Machine makes 3 Radios a Minute. For American consumers of the era it was very novel. The nearly dystopian concept of machines making more machines received equally strong responses of awe and paranoia.
Actually it finished a complete radio once every 20 seconds. The E.C.M.E. (Electronic Circuit Making Equipment) was a British innovation in automation. Another fine product of Sargrove Electronics way back in 1947. Sargrove Electronics was a fine product of John Sargove, an engineer who is too often ignored in the history of radio. More here.

Sargrove was born in 1906 John Adolphe Szabadi. He changed his name to Sargrove in 1938 and dropped the "e" from Adolphe while he was at it. He worked at British Tungsram Radio Works. they had him working on a universal vacuum tube. The Sargrove UA55 worked fairly well. Bu twhat interests me today are his experiments spraying metal onto Bakelite to create circuits. It worked. These were early circuit boards. These were before both thick film integrated circuits and printed circuit boards (PCB). Strangely neither patent went to Sargove. He did patent some processes relating to his automation in the late 40s, but not the actual board! I'll also point out that this is also a definitive step in the birth of the microchip.

At Sargrove electronics, his automaton used a spray-circuit technique. It was faster than any previous method. All the normal human errors of hand-wiring were eliminated. the automation even tests it's own work , determining the exact location in the circuit of the flaw. Bakelite blanks were fed into the machine and a series of inductors, capacitors, resistors, and potentiometer tracks are sprayed on in layers then lacquered for protection. Only the speaker and the tubes needed added by hand. The end product was cheaper, lighter and stronger than the old hand wired units. The young company was bankrupted by a large order from India that was canceled. Sargrove was liquidated to pay it's debts in 1947 and it's assetts were purchased by Solent Steel Fabrications.