Location of Philo Farnsworth’s Green Street workshop in San Francisco, California, the spot where electronic television was invented. Original lab is gone but a nice memorial and plaque still remain.
From the Wikipedia: Farnsworth developed the vacuum tube television display, an idea he conceived at age 14 and developed at age 21. During a patent lawsuit against RCA his high school teacher redrew a drawing Farnsworth had made on the blackboard when he was 14. Farnsworth won the suit and was paid royalties but never became wealthy. The cathode ray tube configuration developed from Farnsworth’s work was used in all television sets and other kinds of displays until the late 20th century when a small portion of televisions were made with alternate technologies such as liquid crystal displays.
Farnsworth developed the Image Dissector, a practical all-electronic image scanning device that made it possible to dispense with the moving parts of mechanical television.