Vintage MASCO model RK-5SLR 7 tube Superheterodyne AM radio receiver with Disc Recorder Unit.  Original old Sams Photofact manual includes schematic, layout, alignment instructions, voltage & resistance test chart, repair parts list. 5 pages. Dated 1952. Mark Simpson Manufacturing Company, Inc. of Long Island City, NY. This manual would make a sensational accompaniment to your classic audio equipment.