Friden 132

           <<<    >>>    ^^^

Friden built mechanic calculation machines before, among others the only mechanic calculator, which could extract a root. The machine shown here is stack-orientated. All layers of the stack are shown as 7-segment cyphers at a cathode ray tube(oscilloscope tube). A steelwire is used as memory, where the data circulate as acoustic waves. This principle was also used for the main memory of the 'big' computers at the very beginning of the development of computers. Just like at a magnetic drum memory, the data is not randomly accessible, which is no disadvantage of a desktop-calculator.