1984 -
Elektronika MK-61
In 1983, Ukraine’s Kvantor, Kvazar, Kontinent and Kosmos started producing the Elektronika MK-61 programmable microcalculator. Retailing for RUB 85, the Elektronika MK-61 remained in production for the next 10 years, a run only surpassed by the MK-51.
The scale on the monitor: 1:1
Compared to the MK-52, this third generation programmable calculator has similar functions along with an extended list of commands, but lacks the non-volatile memory (PROM) and ports for additional memory modules. The MK-61’s system of commands is fully backward compatible with the second generation models (the B3-34 and MK-54), although the B3-34 contained 40–50 steps more than this model.
By the late 1980s, personal computers were becoming more widespread while programmable calculators were falling from favour. In 1988, issue 6 of the Science & Life magazine (in the Man & Computer section) ran an article by S. Komissarov titled Let’s build a microcalculator!. Readers were invited to participate in a group project to design a new programmable microcalculator that would surpass stalwarts like the B3-34, MK-61 and MK-52. The first entries were published in issue 12 (1988) in an article entitled Has the microcalculator been created?, also detailing the MK-61’s glitches.




The MK-61 was a popular platform for games. In his book Calculator — Your Accessory and Adversary in Games, A. Gaishtut mentions some of the many game design manuals which were being released at that time. People were creating a new wave game programmes for the MK-61 which explored the device’s potential for graphic and dynamic elements.

Using reverse Polish notation and equipped with an eight-digit vacuum fluorescent display, the MK-61 had 15 address registers and 105 programme steps.

The calculator ran on three A-316 batteries (equivalent to today’s AA batteries).
Dimensions: 170×80×38mm
Weight (without batteries): up to 250 g

Sources: http://www.myadel-gimnaz.by/node/443, https://ru.wikipedia.org/wiki/%D0%AD%D0%BB%D0%B5%D0%BA%D1%82%D1%80%D0%BE%D0%BD%D0%B8%D0%BA%D0%B0_%D0%9C%D0%9A-61.