Prinztronic SR88M

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Calculators: Handheld: Prinztronic SR88M (type II)

		Size (approx):	88mm (max) x 135mm x 25mm (max) (w,h,d) Weight 152g excluding batteries
		Power:	4.8 to 6V DC, 4 x AA size battery, 0.5W. Also accepts adaptor/charger DC 6V, 100mA through top side socket on the right. The battery compartment cover has a small table showing when an adapter/charger can be used; Ni-Cd and no batteries is OK, but manganese and alkaline is not. Quoted battery life for manganese or Ni-Cd is 3 hours.
		Case:	Solid thick beige plastic case with black lower section. Stippled black plastic keyboard surround with a small piece of brushed aluminium around the top three keys and on/off button. Green display filter has the name and model number printed in white. The keys are quite squishy and have a soft click.
		Display:	8 digit green VFD with a ninth digit for negative and memory indication
		Features:	Basic four function with percentages, sign change, square root, and seven fucnction memory
		Age:	1975
		Manufacturer:	Made in Japan (for Dixons). Serial No. 564895 (also 501740).
		Comments:	Built to last, and it has. Simple yet effective calculator that is easy to use. Original black plastic case has flap and tuck over the top. Buttons are squishy but surprisingly positive. Battery compartment door has power guide and compartment has a ribbon to extract batteries.

Components:
Boards:
Construction:	Very very difficult to open as the stiff case sides are held together by sturdy lugs. Even though there is a lever slot at the top you are sure to mark this calculator trying to open it - I would advise strongly against it.

Logic comments:	The (C) button is used once to clear entry of a number, a second time to clear the calculator, so it is (CE/C) really
	Input overflow is suppressed, keying a ninth digit is ignored
	Negative numbers are flagged by a "-" sign in the far left (ninth) digit thereby allowing full eight digit negative numbers
	Overflow shows the shifted result and "C" (or "E" for negative) in the far left (ninth) digit and is not recoverable.
	Divide by zero shows zero and "C" in the far left (ninth) digit and is not recoverable
	There is automatic constant on multiplication and division only
	Memory store is indicated by the decimal point of the far left (ninth) digit
	Memory usage is basic: To store 9 in the memory key (9)(M=). However, the (M=) will act like a M+ function use (RM) twice to clear
	You have to be careful that you do not key in such things as: (n)(+)(M=), (n)(X)(M=) as very confusing things happen
	Negative square roots are not allowed and result in zero with "C" in the far left (ninth) digit and is not recoverable
	Sign change can be used in mid-number entry.
	It suffers the pseudo fixed decimal bug: key in (1)(+)(.)(0)(0)(0)(=) to get "1.000" which remains a three digit fixed decimal until more digits are required or you use multiply or divide
	It suffers the negative zero bug: (1)(-)(2)(=)(+)(1)(=) gives "-0"
	It suffers the divide to negative zero bug: (1)(/)(1)(0)(=)(=)(=) etc will eventually end up as "-0"