Vintage Radio Service Manual - ARVIN model 664 & 664A (Chassis No. RE-206-1) model 6640 (Chassis No. RE-206-2) 6-tube Superheterodyne AM radio receiver. Manufactured by Noblitt-Sparks Industries, of Columbus, IN. Dated 1947. 4 pages. Original old Sams Photofact manual includes schematic, layout, alignment instructions, voltage & resistance test chart, repair parts list and description. This manual would make a sensational accompaniment to your retro audio equipment.