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Rich, I''m interested in the interface. What would you sell it for?

is there any value to these anymore? got computer, printer and cassette interface all in good condition. frcwrx@msn.com

MK-85 and Casio (or this Tandy) looks like two coins because soviet engineers simply take the interface modules (screen and keyboard) from cheaper pocket computer (Casio PB-100) and placed over their own platform $ PDP-compatible 16-bit chipset. Result is strange $ big computer (MK-85 can work with very big numbers $ over to 10^4000) is closed in calculator''s cage with small screen and ugly keyboard. Add there lack of any interfaces to make a program backup (there are no tape recorder or printer ports in MK-85) and you can fully imagine this strange pocket computer. Programs are saved in 2K volatile memory divided to ten parts without any chance to make a hardcopy.
Many of MK-85 still work today like new. Think, what today''s pocket devices can still work over 20 (MK-85 manufactured up to 1991) or near 30 years like Casio?

I have one of these that I bought new not too long after it was released in 1982. I used it in college classes and did some basic programming on it. The PC4 that I have still works fine in as of May, 2011. I just changed the batteries last year and powered it up to make sure it still works. I used to have the cassette interface for it too, but that was lost years ago in a move.

Looks similar to Electronica MK-85 made in USSR (1986)

http://www.leningrad.su/museum/show_calc.php?n$172
http://ru.wikipedia.org/wiki/$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-85
http://mk85.narod.ru/about.htm