Sharp EL-513

Brief History

After launching the EL-512 programmable scientific calculator produced from 1981, a simpler version has been developed, which can store up to only 31 program steps (EL-512: 128 steps), and has only 5 memory registers (EL-512: 10), and lacked more scientific and statistics functions. The EL-513 is identical to EL-504 introduced in 1979, but it is thinner and smaller than that.

The ON/OFF button is interesting compared to Sharp scientific models, and the angular mode selection method is rather unusual.

Technical specifications

Manufacturer:	Sharp Corporation (Japan)
Mfg. date:	1982-85
Size:	6,9×12,8×1 cm
Weight (ready for operate):	70 g
Type:	programmable scientific
Capacity:	10/8+2 digits (input/display) 12+2 digits (internal precision)
Operating logic:	algebraic with precedence
CPU:	SC43319A
Registers:	2 standard (with saving the pending operation) 1 constant (with saving the pending operation) 15 bracket (with saving the pending operation) 5 memory (with aritmetic)
Features:	+/-change sign (direct entry of negative numbers) RVexchange registers (X-Y) Ffloating-point notation Fixfixed-point notation: the listed decimals can be chosen (0-9) Sciscientific (exponential) notation Sqrsquare root x²square pivalue of pi (3.1415..) can be recalled 1/xreciprocal trigtrigonometrical functions (sin, cos, tan and inverses: arcsin, arccos, arctan) hyphyperbolic functions (sinh, cosh, tanh and inverses: ar sinh, ar cosh, ar tanh) DMS-DDconversion of decimal and sexagesimal numbers logexponential and logarithmical functions (10- and e-base) y^xraising to power SDone variable statistics: calculating mean and standard deviation P-Rconverting coordinates between rectangular and polar systems n!factorial
Display:	11+1 digit LCD
Power:	2×LR44 button cell
Programming method:	keystroke-programmable
Program capacity:	31 keystrokes
Test results:	trigonometry:result of sin^-1(cos^-1(tan^-1(tan(cos(sin(60°)))))), reference value: 60. 60.0000050142 exponential:result of 0.999¹⁶⁰⁰⁰⁰, reference value (first 14 digits): 3.0068804206375×10^-70 3.00688090276E-70

Pictures

EL-513

Inside of the EL-513

Detailed description

At power-on, the calculator computes trigonometric functions in degrees (DEG mode). To switch between degrees, radians and grads, press 2ndF DEG, RAD, or GRAD. The currently selected unit can be checked by pressing 2ndF ANG. The „o” symbol appears on the display show the selected unit.

The calculator can handle parentheses up to 16 levels, and the first 4 levels can be checked via the „(„ indicators in the upper line of the display.

To store a number into K1..K4 memory register, press 2ndF STO and the appropriate K button (K1, K2, 2ndF K3 or 2ndF K4. To recall the stored value, press the appropriate K button. The displaying result will be generated by multiplying the K memory contents with the number on the display.

Programming is very simple, but it is not possible to modify or correct a stored program. Entering the programming mode with the 2ndF LRN keys, the previous stored program will be cleared. Every key pressed counts one step in the program. End of the program must be programmed by pressing 2ndF LRN, and while it counts 2 steps, programs only up to 29 keystrokes can be stored.

The stored program — to displaying results — can be paused by pressing 2ndF LOOK. In this case, a „LOOK” indicator appears on the display. To continue running the program, press COMP.

To input values from keyboard at run-time, a (x) command required. The number of variable can be seen between brackets (except the 11. and further variables, which can be used but there isn’t any identifier displayed.