The Grudig Company in Germany was started by radio dealer Max Grundig after World War II to produce radio repair instruments. It expanded into radio set production, making the Heinzelmann in 1946 and the Grundig Boy in 1949 that was one of the first portable cabinet radios. Grundig took over the Lumophon factory in Nuremberg and in 1951 began production of its first tape recorder, the Reporter 300. In 1952 it made its first portable tape recorder, the Reporter 500 L. In 1954 the Stenorette A became Grundig's first dictation machine, nicknamed "tree frog" because of its green colour. The maximum recording time is around 30 minutes at a tape speed of 6 cm/s. In1955 Grundig made the Music Cabinet 7080 W/3 D, nicknamed "leaning Max" because of its slanted feet. Two doors open the radio and record player and a 10-record changer. In 1957 the largest tape recorder factory in the world is created in Bayreuth, and produced the Portable Tape Recorder TK830 with two tape speeds, a 3-D sound button and a sound level indicator with a visual dial. Fully transistorised pocket receivers were made in 1958 as the Transistor-Box and the Pocket Transistor Boy. In 1965 the Cassette Recorder C 100 is the first cassette tape recorder made by Grundig. Recording takes place with the DC International System, on cassettes with the dimensions 120 x 77 x 12 mm. The Car Cassette Tape Player AC 50 brings cassettes into cars.