Sinclair Oxford 200 (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: Sinclair Oxford 200 (Type I)

	Size (approx):	73mm x 155mm x 30mm (max) (w,h,d) Weight 124g excluding batteries.
	Power:	9.0V DC, 1 x PP3 size battery. Accepts an adapter (undefined) through socket on the top side to the far left.
	Case:	The two-piece smooth black plastic case with a tilted display area. This raises the top area to be large enough to fit the battery. There is a purple display filter that give a bright image but the viewing angle is quite limited. The blue and grey keys are short travel, positive click type and work OK on this example. The case front has white printed text for the model name and key labels and blue print for the model number/logo. There are no stickers on the rear side.
	Display:	8 digit red LED with bubble lens with a ninth digit for negative and error indicators.
	Features:	Standard four functions, percentages, and five function memory.
	Age:	1974
	Manufacturer:	Made in England by Sinclair Radionics Ltd, London Road, St. Ives, Huntingdon, Cambs, PE17 4HJ. Serial number 795325 on sticker in battery compartment.
	Comments:	Classic "Oxford Series" calculator from Sinclair. There is a second type (Oxford Type II) with VFD display and narrower surround to the display. The logic is sound in all aspects but the lack of memory indication is annoying. I do not think that it came with a cover.

Components:
Boards:
Construction:	Cannot find a way to open it and I do not want to damage my example. Can anyone help?

Logic comments:	The clear key (C/CE) is used once to clear an input number on the first press and to completely reset the calculator on the second
	Overflow on the input of a number is suppressed, typing in a ninth digit is ignored
	There is automatic constant on all four functions
	Memory storage is not indicated - you have to remember it
	Negative numbers are flagged by a "-" in the immediate left hand digit, travelling into the far left (ninth) digit thereby allowing full eight digit negative numbers.
	Memory use is by two key sequence, press the (M) key then use the white labels
	A divide by zero shows "C" in the fare left (ninth) digit and is recoverable using (C/CE)
	Overflow shows the result and "C" ("E" if negative) in the far left (ninth) digit and is recoverable using (C/CE)

box

The two images to the left show the front and rear of the box. It measures 215mm x 93mm and is 38mm deep. It is quite a bit longer than the calculator as it houses a felt-effect blue plastic former which holds a 9V battery as well as the model itself. It looks like it is printed in three-process colour (if there is such a thing) and has no origin or reference information.

The rear image is a bit misleading as the adapter shown is an optional extra.

manual

The manual measures 72mm by 155mm and is 20 printed pages. Text is blue and black throughout. Good descriptions and plenty of examples make this manual quite useful. This example is English language only.