Eisler was born in Vienna, and qualified in engineering at Vienna University in 1930. After some time in Belgrade installing radios into trains, he returned to Vienna where he worked as a printer. In 1934 he was forced out of his job by the Austrian fascists and, armed with some patents, he left for England in 1936.
Initially unemployed and - with no work-permit - unemployable, he began to make a radio with a printed circuit board in his Hampstead boarding house. While trying to sell his ideas, he was taken on by the Odeon to work on their cinema technology, where he had the idea of covering the seats with a blotchy yellow fabric. The cinemas were plagued by children who would wipe their ice cream on the seats, but with the new fabric, any sticky seats could marked with 'reserved' signs and removed for cleaning at the end of each day with no customers any wiser or stickier.
Eisler succeeded in evacuating some of his family from Austria, but on the outbreak of the Second World War was interred as an enemy alien for a time. Following his release, he eventually managed to convince a lithograph company in Camberwell to take on his idea of printed circuits in 1941. As a sign of faith, he signed the contract without reading it and unwittingly signed away his future rights. In 1943 he took out a patent for using printed circuits in a variety of products: cables, interconnections, aerials, transformers, motors, valves and heated wallpaper. However, he found no demand for his product until the Americans started work on the proximity fuse to bring down V1 rockets, and for which printed circuits were vital.
Following the end of the war, the USA released the secret of printed circuits, and from 1948 all electronics in airborne instruments were printed. He established a new firm, Technograph, but disagreements mounted and Eisler slowly moved away from the company. In 1957 he resigned to start freelance work on heating films for floor and wall coverings, as well as for foods such as fishfingers. Heated wallpaper caught the popular imagination and briefly looked viable until the discovery of North Sea gas ensured cheaper gas heating and dealt the wallpaper a fatal blow.
Eisler was responsible for a number of other popular developments, including the rear windscreen heater, heated clothes and also a pizza warmer, to enable a customer to keep his takeout pizza warm by plugging the box into a battery powered by the car. Like so many of Eisler's inventions, however, it never made the transition from idea to commercial success.