sharp el-512

this is one of several sharp scientific models. small and compact, its very powerful and in many ways superior for its time.

the unit is well made and comes in a wallet case (not shown here). it has a good set of scientific functions including hyperbolics, polar/rectangular, 2d statistics, linear regression, hex and decimal conversion, nine memories and its programmable with a 128 step capacity.

there are some other nice features like the ten digit display, brackets implied multiply and the sunken on button to avoid accidental power up. all modes and programs are non-volatile and the scientific functions have good accuracy and domain range (early casios refused to trig at 1440 degrees).

the programmability is not so hot, however, because the memory is designed for formula. there are no jumps or loops. however, the program can prompt for input of several terms and can display intermediate results using the LOOK function. four such programs can be accommodated.

there are some recent copies of some of these like this one.