Operating the Curta

Setting a number on the input section

the setting levers

Rotating the crank

click high on the handle for a fast turn click low on the handle for a slow turn


Once a crankcycle is running it can not be stopped.

Add or Subtract mode

the red ring shows you are in subtract mode

Moving the carriage

click on the shaft you would like to position in the unit position the little green dots show the position of the carry lever actuating pin

See the little green dots on the wheels? They show the position of the carry-lever push-down-pin on the rear side of the wheel.

Turns counter reversing lever

the turns counter reversing lever

The reversing lever controls the way the crank turns are counted.

Clearing the Results and Turn Counter

click any part of the lever to turn it in the operating position click any of the 8 hotspots to start a clearing turn when done click the plunger to fold the lever in storage position

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