sumlock anita 810

the 810 was the first of the hand-held range of anita calculators from sumlock comptometers and manufactured by rockwell in 1973.

this is a fine example in almost perfect condition. the display is 8 digit led whose segments themselves appear to be made up of smaller dots. it is very well constructed and palm sized. the form factor reminds me of the fx-20 or the hp-25, a size i find convenient.

the on switch doubles as a means to select power from an external supply and the other switch selects rounding indicated by a rounded arc. rounding is fixed to 2 decimal places for accounting purposes.

although pocket sized, this unit was clearly intended for use in accounting because operationally it behaves like a desk calculator. that is to say that add does not chain to multiply. so 2*3+1 is not 7. instead, you press 2*3=+, 1+ and to subtract to press, for example, 3- rather than -3. this is exactly how most desk calculators operate like the anita 811sl. a clue to this is the subtle colour shading of the plus and minus keys.

click on the calculator to run simon southwell's anita simulator. more info here.


the machine is protected by a rather suave faux leather, stitched, tab fold case.
the back of the machine is brushed aluminium complementing the front facia and giving the machine a rather cool 70's retro look. the back slides up revealing the battery compartment which takes 3 AA batteries.

the exposed top inside hosts a label reading, "sumlock anita ltd. uxbridge england."