From 1919 to 1923 he studied electrical engineering in Munich.
He worked there from 1923 to 1929 as assistant of Professor Max Dieckmann, with whom he operated a television station at the Verkehrsausstellung (lit: Traffic exhibition) in Munich in 1925. In the same year Hell invented an apparatus called the Hellschreiber, an early forerunner to the fax.
Hell received a patent for the Hellschreiber in 1929.
In the year 1929 he founded his own company in Babelsberg, Berlin. After World World War II he re-founded his company in Kiel.
He kept on working as an engineer and invented machines for electronically controlled engraving of printing plates and an electronic photo typesetting system called digiset marketed in the United States of America as VideoComp by Radio Corporation of America and later by III. His company was taken over by Siemens AG in 1981 and merged with Linotype in 1990, becoming Linotype-Hell AG.
Rudolf Hell died in Kiel, Germany. Hellschreiber is still in use today by Amateur Radio (Ham) operators around the world.
The Feld Hell Club holds monthly contests and gives out awards for hams who make contacts using this unique mode of communication.