Calculating - Exactus
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Exactus
Model   Sterling Mini-Add
Maker    
Origin   England
Date    
Serial    
 
A small, pocket sized calculator. Like the Addiator, a stylus is used to move the numbers up or down. However, to change between addition and subtraction a hinged plate is raised or lowered rather than turning the Exactus over.
 
To add, the number is pulled down to the bottom if it is silver or up, round to the left and down if it is red. To subtract, the number is pulled to the top if red or down, then round to the left and up if silver. The small size and the hinged flap make the Exactus fiddly.
 
I find it easy to make a mistake on the Exactus while the Addiators are much more usable.
 
 
 
 
 
     
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