Vintage Radio Service Manual - AIR KING model A-410 (Revised) 4-tube portable (battery operated). Superheterodyne AM radio receiver. Manufactured by Air King Products Company, of Brooklyn, NY. Dated 1948. 4 pages. Original old Sams Photofact manual includes schematic, layout, alignment instructions, dial cord drive, voltage & resistance test chart, repair parts list and description.  This manual would make a sensational accompaniment to your retro audio equipment.