The SHARP EL-5001 Scientific Calculator is the little brother of the PC-1201, the ancestor of all SHARP Pocket Computers! This calculator, launched in 1977, is slightly bigger than the PC-1201 but has the same look & feel. The untrained eye could easily take one for the other. They both use a VFD display and have the same brushed aluminum case and similar keys layout. Really alike! In addition, they both have manual switches – mode selectors – along the right side of the calculator. The EL-5001 has the common angular mode selector on the bottom, and, more surprisingly, a memory selector on the top. Indeed, the calculator has two memories that can either be used to store values (business as usual) or as two levels of parenthesis!
The EL-5001 comes with a set of six applications in ROM, a.k.a. Special Calculations: Plot Calculation, Statistical Calculation, Calculation of Quadratic Equations, Integration, Complex Number Calculation (&Coordinate Conversion) and Vector Calculation. Pretty good for the 70s’. But the most interesting feature is arguably the top four un-labeled keys and the associated windows and rotary selector. Check-out the video in this post to see it in action! By rotating the wheel, the user selects one of the six applications. The windows display accordingly the function keys’ labels and re-defines several keys of the machine. Many modern calculators are offering such soft menus but using the LCD screen to display the key labels. 41 years earlier, SHARP did it in a purely analog way!