Calculating - Arithma
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In The Hand
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Addiator Arithma Junior
Model    
Maker   Addiator
Origin   W.Germany (marked Foreign)
Date   1960s
Serial    
 
A pocket calculator for sterling currency.
 
The stylus, carried clipped to the side of the Arithma Junior, is used to slide the bands up or down as required.
 
The top set of numbers is used for addition. If the number is white it is pulled down to the bottom. If red it is pulled up to the top, round to the left and down to carry to the next column.
 
The bottom set is for subtraction. This time, if the number is white it is pushed up to the top and if it is red down to the bottom, round and up to the left to carry. That means that in either addition or subtraction, white is to the middle and red is away from the middle.
 
The result is shown in the central display.
 
The arithma has a soft carrying case.
 
 
 
   
Addiator Arithma Junior
Model    
Maker   Addiator
Origin   Germany
Date   1960s?
Serial    
 
A pocket calculator for decimal calculations.
 
 
 
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