Interesting Article On PRR Automatic Speed Control

Prr7688OGR Forum Member

While doing some poking-around on the web, I stumbled across this article on the Pennsylvania's early automatic speed control system (the grandparent of modern PTC). The article is from a 1951 issue of Popular Science. I've known about the basics of the PRR's system for a long time now, but this article really appealed to as an electrical engineer because it gets into more of technical aspects of the system. Wanted to share so others could enjoy as well!

https://books.google.com/books...ge&q&f=false

4/7/204:09 PM

Original Post

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