Binatone Memory

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Calculators: Handheld: Binatone Memory


		Size (approx):	63-70mm x 135mm x 18-23mm (w,h,d) Weight 70g excluding batteries.
		Power:	9.0V DC, 1 x PP3 size battery. Also accepts adapter/charger (undefined) through a left side socket about a third of the way down. The on/off sliding switch on the right side, in line with the display.
		Case:	Cheap feeling two-piece shiny black plastic case. Edges are a bit sharper than you would normally expect. It has brushed aluminium panels for the brand / model info above the display and keyboard surround below. The body is titled up towards the back and widens at the top to accommodate the 9V battery. Cheap battery terminals are just two metal tags rather than a proper 9V battery connector. The red plastic display filter is flat and slightly inset but gives a decent, if narrow view. Buttons make a positive loud click. Blue and black colour scheme of keys reminiscent of a Texet calculator.
		Display:	8 digit red LED with no ninth digit
		Features:	Basic four function with percentages, change sign and four-function memory.
		Age:	c1977
		Manufacturer:	Serial Number 015532. Made in Hong Kong. QC sticker in the battery compartment states 10 Jan 1977.
		Comments:	The fact that this calculator has a CS button for change sign means it is very very likely to be a Texet calculator. Cheaply made but works well enough, though the logic is a bit poor with lack of recover and pseudo-fixed decimal bug. The original case is soft black plastic with a flip over top and front tuck in band. It has an integral carry strap. See the Same Calculator page for more clones.

Components:	1 x IC: Texas TMS0972NL KDS 7646 (week 46 of 1976), 28 pin DIL, 0.3" width 1 x 8 digit LED module with individual bubble lens; Lan-B-1
Boards:	As basic as you can get with one main board (RJP 0972-761006C) set with two plastic pillars. The reverse side of the board is the keyboard contacts.
Construction:	Difficult top open as this was never designed to be repaired. There are numerous plastic lugs along all the edges. Best success was found starting at the sides pushing the upper section inwards. If in doubt -don't do it!

Logic comments:	CE cancels the last number entered whilst (C) clear the whole calculator
	Input overflow is suppressed; inputting a ninth digit is ignored
	There is automatic constant on all four functions
	Negative numbers are represented by a "-" sign in the immediate left hand digit. As there is no ninth digit to travel into you are limited to seven digit negative numbers
	The change sign function can be used in mid number entry and before
	Divide by zero results in a flashing zero which is recoverable using the (CE) key
	Overflow shows the result flashing and is recoverable using the (CE) key
	There is no indication of memory store - you have to remember it!
	Overflow in the memory wipes the contents after recovery using (C)
	This calculator suffers the pseudo fixed decimal bug; try entering (0)(.)(0)(0)(0)(+)(1)(=) to give "1.000" which remains a three decimal number until greater precision is required.