“Unlocking the Future: How a Simple Discovery Revolutionized Technology and Changed Our Lives Forever”
The triode or Audion, invented by de Forest in 1906, was similar to the diode but with an extra component: a metal grid between the anode and the cathode. Applying an electric charge to the grid repelled electrons coming from the anode, allowing the number that made it through to the cathode to be adjusted. This meant that a weaker current could be used to control a stronger one, allowing weak signals – like those from a radio receiver or telephone – to be effectively amplified. de Forest’s invention launched the modern era of electronics, making possible such breakthroughs as long-distance telephone and radio communications. Triodes were also widely used as electronic switches, being more reliable and less prone to wear than electromechanical relays. Indeed, the earliest electronic computers like the British Colossus – used to break the German Lorentz cipher – and the American ENIAC – used to generate ballistics tables for naval guns – used thousands of networked vacuum tubes to perform high-speed calculations.
However, vacuum tubes had a number of serious shortcomings. For one thing, their filaments needed to heat up in order to work, such that old electronic equipment like radios and television sets often took anywhere from a few seconds to a few minutes to fully power up. They were also fragile, consumed large amounts of power, and generated large amounts of heat, meaning early electronic computers required massive air conditioning plants to keep their processors cool. And while subminiature vacuum tubes just a few centimetres long were developed, these power and heat issues placed a lower limit on the size of electronic circuits. For such devices to be made truly compact and portable, a new, more compact and energy-efficient type of electronic switch was needed.
