> I'm just trying to find some schematics at the moment, it sounds like they used vacuum tubes. Yes - vacuum tubes and relays, cds cells (or maybe selenium cel

> I'm just trying to find some schematics at the moment, it sounds like they used vacuum tubes. Yes - vacuum tubes and relays, cds cells (or maybe selenium cells). Transistors would have been very expensive and fragile, if even available. Here are some links that may help you: http://cyberneticzoo.com/category/cyberneticanimals/grey-walter-cyberneticanimals/ http://cyberneticzoo.com/category/cyberneticanimals/grey-wal... http://www.roboticsportal.it/wp-content/uploads/2014/01/Speculatrix.gif http://www.roboticsportal.it/wp-content/uploads/2014/01/Spec... http://4.bp.blogspot.com/-exHhj_kM47Y/VVknwK5WPsI/AAAAAAAAA5s/nRev66sTAYA/s1600/CircuitLivingBrainp242.JPG http://4.bp.blogspot.com/-exHhj_kM47Y/VVknwK5WPsI/AAAAAAAAA5...