Decimo Vatman Mini MII (type I)

		Home New Stuff Author Links Guest book Web-log	Adverts Bric-a-brac Calculators Components Ephemera Events	For Sale Glossary History Hit or Miss Radios Transport	Ultra Valves Wanted Metal Puzzles Clocks

Calculators: Handheld: Decimo Vatman Mini MII (type I)


	Size (approx):	75mm x 125mm x 19mm (max) (w x h x d) Weight 90g not including batteries.
	Power:	3.0V DC using 2 x AA size batteries. It accepts an adapter (3V DC) through a socket on the top side to the far left. The manual warns of the need to remove “dry cell” batteries if an adapter is used.
	Case:	The case is two-piece smooth black plastic and is very gently wedge-shaped. A large brushed aluminium panel sits flush above the display and is printed black with the model name. An even larger panel acts as a keyboard surround, which wraps around the edges of the calculator about a third of the thickness. They keys are soft with their own escutcheons but suffer bounce in my example. A flat blue display filter sits slightly proud and give a clean bright display.
	Display:	8 digit blue VFD with a ninth digit for negative, memory and error indicators
	Features:	Standard four functions with percentage, square root and four-function memory.
	Age:	1975
	Manufacturer:	Decimo Electronic Calculator but no further manufacturing details. I suspect it was a made by Detron of Korea. Serial number 79077964.
	Comments:	Unusual design for Decimo, which looks very like the model 105 by SVM in France. Also a close match to the Detron 805MD. However, the red keys spoil the blue and silver colour theme. My example comes in a case (which looks original) gold printed “Pye Connectors Ltd”. If this is the original then I think it was a marketing give-away product. The logic is sound with good recovery but let down by negative square roots.

Components:
Boards:
Construction:	Even after removing the screw from the back I still cannot open this calculator. I strongly suspect that there is another screw under the front keyboard surround - does anyone know?

Logic comments:	The (CE) key is used to cancel an entry whilst the (C) key clears the whole calculator
	Input overflow is suppressed inputting a ninth digit is ignored
	Negative numbers are shown with a "-” in the far left (ninth) digit, thereby allowing full eight digit negative numbers.
	There is automatic constant on all four functions
	Divide by zero just shows “C” in the far left (ninth) digit and is recoverable using (CE)
	Overflow shows the result and “C” (or “E” if negative) in the far left (ninth) digit and is recoverable using (CE)
	Negative square roots are allowed and result in a negative answer
	There is indication of memory store by an upper “n” in the far left (ninth) digit

	The manual measures 77mm x 107mm and is 4 pages. Printed in black only it is about as basic (and cheap) as you could make it. It is in English only and obviously made for a generic calculator. There is reference to the model “(M)”, which just means it is the memory version. It even states that the memory indicator could be an “n” or a decimal point (presumably depending on which calculator you have got).		The Guarantee measures 108mm x 193mm and is a two sided orange and black leaflet. It does remind you to put batteries in before sending back you “faulty” calculator!