The Elektronika MK-61 is a third-generation non-BASIC, RPN programmable calculator which was manufactured in the Soviet Union during the years 1983 to 1994. Its original selling price was 85 rubles. The MK-61 has 105 steps of volatile program memory and 15 memory registers. It functions using either three AA-size battery cells or a wall plug. It has a ten-digit (eight digit mantissa, two digit exponent) green vacuum fluorescent display. External links Datasheet for the MK 61 processor 1970s-1980s pocket calculators database Alfred Klomp's page on "Hacking the MK-61" How to calculate on the Elektronika B3-34 (and similar calculators) Elektronika MK-61 Operating Instructions, English translation 250 games for MK-52, MK-61 MK-Compiler easy programming on the MK-61 and MK-52. Emulator Online-emulator of МК-61 (accurate emulation of the calculator's firmware, with automatic input code and output the contents of registers and stack). Emulator of МК-61 for Android (accurate emulation of the calculator's firmware, with ability to save states). Extended emulator of МК-61 for Android Here you can download an emulator of all Soviet Programmable Calculators the page with a description of the emulator Elektronika programmable calculators