Lloytron Accumatic 304

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Calculators: Handheld: Lloytron Accumatic 304 (aka E304)


	Size (approx):	87mm x 138mm x 24-28mm (w,h,d) Weight 156g excluding batteries.
	Power:	6V DC using 4 x AA size batteries. Also accepts adapter/charger (6V DC 300mW series 260A) through a top side socket on the far right. Non-rechargeable batteries must be removed if an adapter is used.
	Case:	Bulky square-sided calculator, the body being made of a two piece glossy black plastic design. There are two end panels, top and bottom, of dull metallic grey and a keyboard surround and escutcheon of similar matt grey plastic - that doesn't quite colour match. The keyboard surround has printed black text for the on/off switch label. A neutral oversized display filter is tilted at about 15 degrees and is printed with white text for the make and model number. The display is large and bright. The keys are large, long travel and bouncy with a soft hollow click. A large metallic sticker on the back gives example and information.
	Display:	8 digit blue VFD with a ninth digit for negative and error indicators.
	Features:	Four function with percentage and square root
	Age:	1975/6
	Manufacturer:	Lloytron, made in Taiwan. Serial number 6C-004396.
	Comments:	Typical Lloyds/Lloytron design though quite a handful to hold. I think the metallic grey is spray-painted on as many examples appear to have scuffed surfaces. There is an unsettling delay on switch on, number input and calculations (square roots take up to 3 seconds). The logic is OK apart from lack of recovery and fixed point bug. The original case is soft black plastic with flip over flap that tucks in at the front.

Components:	1 x cpu: Sharp L12006 5L2 023 (2nd week of November of 1975) 28 pin DIL , 0.6"width 1 x 9 digit VFD: single glass tube, round faced 2 x transistors 5 x diodes 7 x capacitors 8 x resistors 2 x resistor arrays 1 x transformer: DCT-04 TDK Japan
Boards:	The keyboard assembly sits loose on top of the main cpu board and battery compartment and is joined by 16 strong wires. The whole board assembly sits loose in the calculator.
Construction:	Very difficult to open without doing some damage. Gently push in the rear section sides whilst carefully popping the lugs down each side. The front section will hinge off the top. Do not force it, it took me ten minutes of gentle pushing and squeezing to open it without damage!

Logic comments:	The (CE) key is used to clear the last entry whilst the (C) key clears the whole calculator
	Overflow on the input of a number is suppressed, typing in a ninth digit is ignored
	There is automatic constant on multiply and divide only
	Negative numbers are flagged by a minus sign in the far left (ninth) digit thereby allowing full eight digit negative numbers.
	Divide by zero shows zero and "C" in the far left (ninth) digit and is not recoverable
	Overflow shows the result and "C" (or "E" if negative) in the far left (ninth) digit and is not recoverable
	Negative square roots are not allowed and result in zero with an overflow which is not recoverable
	There is a fixed decimal bug, try; (0)(.)(0)(0)(0)(+)(1)(=) gives "1.000" which remains with three fixed decimals until you use multiply or divide or more are needed.