Elektronika MK-90

Manual 11.6MB PDF PSU 65KB PDF SCH 1.95MB PDF MOD 623KB PDF

"Have you heard about MK-90? It was a BASIC machine, with cartridge-like memory, large LCD screen (something like 6x20 symbols, I think, all pixels fully adressable). It came with two cartridges - one empty (for writing BASIC programs), and another with machine-coded Tetris (which is funny because the manual didn't say anything about machine code programming, and if you inserted this cartridge and tried to save your BASIC program, Tetris was gone forever. Cool machine, but I saw it only once (there was an all-Union contest among 11-graders, and a winner got it as a prize). In fact, I hoped to find its picture here :)

- Gregory Escov

And here it is!!

Click on the image for a larger view.

The keyboard overlay. The MK-85/M also uses a keyboard overlay.

The backplate. The price: 1500 rubles! © Sergei Frolov An earlier backplate (1988) with an astronomical 3500 rubles price-tag!

This proved to be an extremely difficult-to-find machine. The astronomical price gives some indication of the reason; this machine was simply too expensive for most people to buy. 1500 rubles was more than 6 months' average salary!

The packaging has an almost 60's science-kit feel.

The goodies inside include ROM modules, batteries, transformer, manuals and the MK-90.

One of the plug-in ROM modules.

The display is surprisingly excellent. This picture doesn't do it justice. Crisp, clear - unfortunately the machine is slow.

MK-90:

• 16-bits microprocessor (DEC-compatable)
• RAM - 16 Kb, ROM - 32 Kb
• user accessable RAM = 11824 bytes
• external memory: changable 10 Kb RAM, include user accessable - 8 Kb
• matrix LCD display with 120x64 dots (8 rows x 20 symbols)
• 30 mm x 250 mm x 100 mm
• mass not more than 0.7 kg
• power consumption: <0.2 W
• BASIC (language)

You can find more information about this machine on the manufacturer's MK-90 page (cyrillic).