Vintage FIRESTONE Air Chief model 4-A-20 (Code 5-5-9000-A) 6 tube Superheterodyne AM SW radio receiver. Original old Sams Photofact manual includes schematic, layout, alignment instructions, voltage & resistance test charts, repair parts list and description. 4 pages. Dated 1947. Firestone Tire and Rubber Company of Akron, OH.  This manual would make a sensational accompaniment to your classic retro radio equipment.