DUDEK Emil: Big chunky early calculator that just fits in the hand. Strange stripped-down version of scientific functions with limited accuracy and archaic display notation. Coupled with lack of recovery it is pretty poor really. Oddly reminiscent of the early horizontal series of CASIO calculators. Boards: The keyboard assembly (A8N-E4B) sits loose on the battery area and is joined to the main board (A8N-1A) by 14 stiff wires. Construction: To open the calculator remove the screw from the rear. This does not really help as the case is held together by internal lugs. The easiest way I found was to push in the rear at the top edge and pop the lug. After popping the side lugs, hinge from the bottom. Be very careful as damage can easily result. Eventually the front will lift off. Logic comments: [C] is used to cancel the last number entered and [AC] to clear the whole calculator. There is automatic constant on all four functions. Input overflow is suppressed, inputting a ninth digit is ignored. Negative numbers are represented by a ‘-‘ to the immediate left of the number but as there is no ninth digit you are limited to seven digit negative numbers. Overflow shows only ‘oooooooo’ and is not recoverable. Divide by zero shows only ‘oooooooo’ and is not recoverable. Square roots of negative numbers are allowed and result in a positive number. Transcendental (logs) and trigonometric results are limited to five decimal places. Power raising is allowed for positive integers only and doesn’t require and equals key press: i.e. 28 is keyed in as [2][an][8] where n = int(>0) Pi is held to six decimal places only.