Vintage Radio Service Manual - DELCO model R-1236 & R-1237 6-tube Superheterodyne AM radio receiver. Manufactured by United Motors Service, div of G.M.C., of Detroit MI. 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.