Originally Posted by
The Oberon
there was a Calc5 which consisted of mainly motors, potentiometers and a spring steel tape, this was the really clever one as it performed a Pythagorus calculation mechanically.
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IIRC the metal tape that ran between the two servomotors in the frame in the Calc 5 was made of Manganin. It's remarkable that one remembers such trivia but forgets more important things!
YS