G+_Jon Klinkefus Posted January 28, 2017 Share Posted January 28, 2017 Hello Padre and Brian, On your last show, relays came up as a topic. It might interest your KITA's to mention some relay history on the show. Relays were actually the first signal amplifiers, predating the invention of both transistors and vacuum tubes. You can think of them as the cell towers of their time (in how they enabled communication and even made possible time synchronization for on-time trains). Relays are what made it possible for the telegraph to follow right alongside of the railroad as it went westward, and eventually allowed a telegraph operator pressing a key in New York to make a contact "click" in San Francisco. Normally voltage drops in a wire would make the signal dissipate after a number of miles, and thus long distance wired telegraph communication impossible. But relays, of course helped solve this issue. Relays also made the cross-country lines cheaper by allowing a smaller gauge of wire to be used in tandem with periodic relay points. --Klink Link to comment Share on other sites More sharing options...
G+_Robert Short Posted January 29, 2017 Share Posted January 29, 2017 also adding the different types (Mechanical and solid-state ) and when to use and how to use as sometimes they will need a Cap or Coil to reduce false triggers. Link to comment Share on other sites More sharing options...
G+_David Wiggins Posted January 31, 2017 Share Posted January 31, 2017 I had no idea about relays on telegraphs. Very cool. Thanks for the history. Link to comment Share on other sites More sharing options...
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