Did you know that a Canadian is responsible for the battery-less radio?
He was interested in radio as early as 11 years old. As early as 1913, he was noted in local newspapers for his skill at operating a radio station, which at the time was an impressive technical accomplishment.
In the early 1920s, radio transmitters and receivers ran on large and expensive batteries to give the high voltages needed for the vacuum tubes that were used.
By 1925 he had introduced not only a complete radio receiver using the new tubes, but had also produced a “battery eliminator” (power supply), to eliminate the expensive batteries. On August 26, 1925, the Rogers Battery-less radio was in commercial sales. It was the first radio receiver in the world to run from household current.
At a time when a schoolteacher might earn $1000 per year, the top-of-the-line Rogers radio sold for $370.