The Forgotten Tech That Used to Run the World’s Power Grids

Comments · 32

• HO

  @HowToHomeLife · 12 days ago · pinned

  When I was thirteen I went to Sandy's electronics to purchase an SCR (Silicon Controlled Rectifier) to build a hand-drill speed controller I found in a Popular Electronics article in 1961!  David Riddle

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• MA

  @martinhaub6828 · 11 days ago

  Very interesting and a nice tribute to those brilliant guys who figured it all out. I remember having a mercury arc rectifier in the tool shed of the farm. It ran motors for the grain silo or something. That eerie, hissing, bluish thing seemed like an evil being from hell.

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• BO

  @bobair2 · 11 days ago

  An interesting video with much information about the SCR. I like it. 😊

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• JO

  @johnmarkbrailsford24 · 9 days ago

  Thanks for this well-researched article on solid state power supplies.<br>Before mercury-arc rectifiers there were rotary converters, used in substations to convert alternating current to direct current for traction purposes. One turn-of-the-century example was still in use in 1986 at Arco do Cego tram depot in Lisbon, its armature perpetually spinning away. One year earlier I encountered an octopus-like mercury-arc bulb at Laxey depot on the Iale of Man, glowing blue as it supplied traction current for the Manx Electric Railway from Douglas to Ramsey. Germanium rectifiers were used experimentally in 1955 on electric trains of the Lancaster-Morecambe-Heysham line in northern England.

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• ED

  @edwardmontague2021 · 9 days ago

  Those Mercury rectifiers you&apos;re showing, are small in comparison to what I once encountered. It must of contained about a bathtub amount of Mercury, had stairs that you climbed to get around it. Was on the third floor of a technical institute and &nbsp;had been &nbsp;used to transmit D.C power across a stretch of water. Again, the Dinosaurs not realising their extinction event had already happened and the kT boundary was decades old.

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• RA

  @rayoflight62 · 7 days ago

  I used two SCRs in antiparallel to simulate a Triac for a drill speed controller, well before Triac become a common component in the electronic market. Triac could be fired in each of the four quadrants, while SCRs in antiparallel would accept a trigger in two different quadrants. I used low power SCRs (in a TO-92 case) as 1-bit static memory, in devices like combination locks, slide projectors, or simple logic gates embedded in power devices. The circuitry to un-trigger the DC-powered SCR was its own garden variety, with a transistor shorting the SCR or a capacitor and a second SCR that briefly zeroed the voltage across the main SCR.<br>Another design sub-sector used uni-junction transistor to provide train pulses for firing an SCR asynchronously in lighting application. Myself, and other industrial designers, used rectified AC to allow the control of incandescent lamps with a single SCR instead of a Triac. Nobody ever found a solution to the inability of phase partialisation circuits to self-trigger in presence of inductive loads, or in case of voltage spikes caused by electric motors or sodium lamp ballast across the power line.<br>Thanks for the video.<br>Greetings,<br>Anthony

• AF

  @afgnh2836 · 12 days ago

  Fascinating look at a pivotal moment in engineering history. The shift from mercury-based systems and fragile tubes to silicon devices really shows how far power electronics has come. ⚡🔬

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• NA

  @naughtiusmaximus830 · 11 days ago

  They just threw all these into the chicago river.

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• MA

  @martinrascon1350 · 4 days ago

  TARTARIAN MERCURY RECTIFYING REACTOR

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• TH

  @TheKelikat · 9 days ago

  значит тиристор в моторах изначально был придуман электриками

• 19

  @1906Farnsworth · 7 days ago

  So how is an SCR a replacement for a rectifier? Wouldn&apos;t a plain diode(s) do the same job? Does a Mercury rectifier have a gate input?

• GS

  @gsmollin2 · 7 days ago

  Ignitrons were great. Until SCRs happened.