Philo Farnsworth: from farm to fusor
Stories from Physics for 11-14 14-16
Philo Farnsworth was an early pioneer of television technology and a prolific inventor. Among other things, he developed a device to sterilise milk using radio waves.
Farnsworth’s family had moved to a log cabin built by Farnsworth’s father in Beaver, Utah, when Farnsworth was 12 years old. In the attic of the cabin, Farnsworth discovered a set of scientific books and magazines. The curious boy devoured the contents of the texts and, inspired, installed a motor to power the family washing machine. Whilst still in high school, Farnsworth began working on television technology.
Previous attempts at developing television systems had used mechanical spinning discs, but he proposed a fully electronic system using a scanning electron beam. He claimed he had the idea for the scanning beam whilst ploughing lines on the family farm. Farnsworth received backing from two philanthropists and, fittingly, the first image he showed his backers on the new technology was an image of a dollar sign.
The Radio Corporation of America (RCA) offered to buy Farnsworth’s patents, but the inventor refused as he felt the financial tie would limit his freedom. The company sued Farnworth and, in court, RCA’s lawyers mocked the idea that a schoolboy could have developed the technology. Farnworth’s defence team called his former chemistry teacher as a witness because the schoolboy had shown his teacher early schematics for his invention and RCA eventually lost the case.
In addition to these inventions, Farnsworth patented the notion of the circular sweep radar display which is still used in radar systems today. Farnworth is co-credited with the invention of the Farnsworth-Hirsch fusor, a device that causes nuclear fusion by accelerating ions in an electric field.