Vintage DETROLA models 571, 571A, 571B, 571A, 571AL and 571BL Superheterodyne AM radio receiver. Original old Sams Photofact manual includes schematic, layout, alignment instructions, voltage & resistance test charts, repair parts list and description. Dated 1946. 4 pages. International Detrola Corp., of Detroit, MI. This manual would make a sensational accompaniment to your classic retro radio equipment.