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Four Gallium Arsenide and/or Phosphide LED's: Texas TIL209 (c Science Museum Group © The Board of Trustees of the Science Museum
Four Gallium Arsenide and/or Phosphide LED's: Texas TIL209 (c.1970); Monsanto MV54 (two on package) (c.1971); Bubble 7 segment used in Sinclair calculator (c.1973); Four other unknown.