Models were produced under the names Rogers Majestic and DeForest-Crossley.(In 1928, the name was changed to Rogers Majestic Corporation Limited). Standard controlled both Rogers Radio Tube Company and Rogers Batteryless Radio Company - the latter, the manufacturer of the receivers. Their father, Albert Rogers, had financed the operations with a holding company incorporated as Standard Radio Manufacturing Corporation Limited. For the ensuing two years, these Rogers radio receivers were the only batteryless radios manufactured in North America.Īfter developing this revolutionary receiving tube, Ted Rogers and his brother Elsworth started a new company to make receivers using these tubes and the rectified power supplies. In August of 1925, the first Rogers Batteryless Radio Receiver was publicly unveiled at the Canadian National Exhibition in Toronto. Neither the 6-volt "A" batteries nor the 45-volt "B" batteries were necessary. Ted Rogers applied their principles to develop a rectified A.C.-power supply to substitute for the high-voltage "B+" batteries in receivers. had been invented, they were not used in broadcasting - neither for home receivers nor for transmitters. In addition, while rectifier tubes that could convert A.C. This development eliminated the hum when the heater was applied with alternating current. That sleeve became the "cathode" element, and the filament was re-named as a "heater" for the cathode. Rogers' invention shielded the filament with a metal sleeve so that the sleeve was heated by the filament inside it. These early tubes used a filament (as in a lamp) for the "cathode" element (when it was activated, it became hot and emitted electrons). Before Rogers' invention, alternating current could not be used to heat the filaments of tubes because of the severe hum caused in the receiver. This proved to be a major advancement for radio - particularly so for receivers. His achievement resulted from his experiments in developing radio tubes employing an "indirectly-heated cathode". (Ted) Rogers of Toronto scored a break-through in radio receivers. Then, in 1902, Fessenden went on to patent another invention of his - the "heterodyne principle" which, as it was perfected, made it easier to tune a radio by using only one instead of as many as four knobs. This set-up served the purpose but it was expensive and unreliable.Įarlier,a Canadian, Reginald Fessenden, had demonstrated in 1900 that radio signals, until then limited to dots and dashes, could be "modulated" to carry voice, music and other sounds. Further, to produce the high-voltage direct current and/or the low filament voltage required by transmitting tubes, electric A.C. The Alternating Current (A.C.) from power systems could not be used for heating filaments in the audio circuits because it produced an obnoxious hum - hence low-voltage batteries were commonly used. Before CFRB came on the air in Toronto on February 19, 1927, radio stations around the world relied on Direct Current (D.C.) for their power supplies as provided by batteries and/or motorized generators.
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