He worked there from 1923 to 1929 as assistant of Prof. Max Dieckmann, with whom he operated a television station at the Verkehrsausstellung (lit.

In the same year Hell invented an apparatus called the Hellschreiber, an early forerunner to impact dot matrix printers and faxes.

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 US as VideoComp by RCA and later by III.

He has received numerous awards such as the Knight Commander's Cross of the Order of Merit of the Federal Republic of Germany, the Gutenberg Prize of the International Gutenberg Society and the City of Mainz, the Werner von Siemens Ring and the Eduard Rhein Ring of Honor from the German Eduard Rhein Foundation (1992).

This German engineer, inventor or industrial designer biographical article is a stub.