Sharp Elsimate EL-120

		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 Vales Wanted Metal Puzzles Articles Clocks

Calculators: Handheld: Sharp Elsimate EL-120

	Size (approx):	170mm x 67mm x 18mm (max) (w,h,d) Weight 134g excluding batteries.
	Power:	4.5V DC 0.6W from 3 x AA size batteries. Does not accept an adaptor. The on/off switch is on the left side, near the bottom.
	Case:	Two-piece case in black and red smooth plastic with rounded top and bottom edges. Elongated landscape format (great if you are right handed, pain if you're not) of slim proportions. The keyboard area is heavily recessed. To the far left a metallic, wrap-around sticker is located in its own recess and printed red and burgundy with reversed out text for the model number. The green display filter is flat but slightly proud and gives a clear bright image. There is an extra "count" thumb switch on the bottom left. They keys are squishy but work well. The count switch is springy with a soft click. The rear has two metallic sticker panels and and unmarked 15cm ruler!
	Display:	3 digit green VFD with a "+/-" symbol cluster to the left and a double-coma cluster to the right.
	Features:	Four function with manual and automatic display shift. Counter function via switch.
	Age:	c1973
	Manufacturer:	Sharp Corporation, made in Japan, serial number 3113296Z embossed on the back.
	Comments:	Can you believe a three digit calculator with nine digit capability, auto display shift and a count-switch? One of the oddest calculators I have ever seen from the 1970s. Logic is weird, display is weird, count function is weird but useful. This is either very good or very bad, I cannot decide!

Components:
Boards:
Construction:	The screw in the battery compartment on my example is jammed - can anyone help with a description of inside?

Logic comments:	(C) is used to clear the calculator there being no cancel entry function
	Input overflow is not suppressed, inputting a tenth digit causes an overflow
	There is no constant on any function other than a half way measure on multiply and divide; (6)(X)(=) gives "36" but it stops there
	The far left symbol cluster is always on, displaying "+" by default
	Negative numbers are indicated with a "-" sign in the far left symbol cluster, thereby allowing full nine digit negative numbers
	Divide by zero shows "1.0.0.0.,," and is not recoverable (the "1" is more like a vertical line from the "+" symbol)
	Overflow shows "1.0.0.0.,," and is not recoverable
	When the result (or input) is more than three digits you can see the next digits by pressing the shift (>) key. The symbol cluster on the far right lights one comma for thousands and two for millions.
	Decimals are displayed (and calculated upon) to three decimal points only
	The "A/M" switch changes between manual (press the (>) key) and automatic display shift. In auto mode, the display cycles between the three possible displays about once a second.
	A thumb switch on the bottom will add one to whatever is on the display - although my example suffers from extreme bounce problems.
	When you use the add switch on long numbers the display defaults to the "millions" or "thousands" so you do not see the increment.