Anyone bought a Russia RPN Calculator?

[Namir]

I have seen on eBay several auctions for Russina RPN (and programmable) calculators. Has anyone bought such a machine? What was your experience?

Namir

[Wayne Stephens]

I own three of them (two MK61's and one MK52 with EEPROM module).

I purchased them mainly due to my interest in Russian history and calculators. They are interesting artifacts. Mine have a "flourecent" LED display (green on the MK61 and Red on the MK52). They are very slow and have volatile memory (i.e. programs, vaiables and stack are lost when the machine is turned off). They are interesting in their rather unique way of displaying the program as you enter it. Across the single line display (from left to right) are shown: the "code" for the last step entered; the "code" for the previous step; the code for the step before the previous step; and finally the actual program step number of the last step entered (each separated by a blank digit).

The volatile memory makes them unfit for any serious programming work (in my opinion). Unless, of course you have the AC power cord, access to 220V 50 Hz electricity and don't mind leaving your calculator on all the time. By the way, the MK61 and MK52 both work off AA batteries. The MK 61 uses 3 and the MK 52 uses either 4 or 5 (I can't recall right now). So, powering them up without the AC cord is not a problem.

I've had fun playing around with mine, and have successfully "converted" several HP11C and HP32sii programs for use on them. To me, though, they are basically toys (but then aren't all the calculators I own over and above the one I use at work "toys"?)

As I mentioned in a previous post, I keep one of the Mk 61 units on my desk at work as a "loaner" calculator. Even those who know RPN are usually intimidated by the Cyrillic lettering on the keyboard. They seldom ask a second time to borrow a calculator.

I'd like to learn more about the module for the MK 52, which appaently allows you to store data so you do not lose it when the calculator is turned off. Unfortunately, the manual is in Russian, and my Russian reading comprehension is almost non-existent. Which reminds me; does anyone know how the module for a MK 52 works?

Take care.

Wayne

[GE (France)]

It's quite unusual to have a red-colored VFD display. Also, the MK-52 has a green display according to this excellent page from V.Thoth's site :

http://www.rskey.org/detail.asp?manufacturer=Elektronika&model=MK-52

This page also carries information on the reading / writing to the EPROM.

If you have used your machines, did you experience some fading of the digits from use ? I have seen a 61 with a somewhat weak display.

[Wayne Stephens]

GE,

You are absolutely correct about the MK52 display. I have not used that one for a while and was working from a faulty memory when I posted my message (at least I don't have volatile memory like the Soviet calculators or I would forget EVERYTHING I know each night when I go to sleep).

The MK 52 does indeed have a green display.

My MK 52 has some slight fading on the right side of the display, but both MK 61's are still bright as the day they were made.

Thanks for the tip about using the EPROM module.

By the way, you don't have a B3-21 or B3-34 you want to sell do you?

Take care.

[cyclist]

I have several Soviet RPN calculators that I have acquired over eBay. Like Wayne, mine are toys and not used for serious calculating. I have the Electronica B3-19M, B3-34, MK-52, MK-54, MK-56 and MK-61.

The MK-56 is a desk top model that I use a Radio Shack 115V to 230V convertor to run. The MK-52, 54 and 61 do indeed run on AA batteries (4, 3 and 3 respectively). I usually use AA batteries that have been run through my camera flash unit so that they are a bit down in voltage. The B3-19M and B3-34 use some odd batteries, but I have a 4 AA holder and alligator clip leads to get these to work.

I haven't tried to program any of the programmable ones, I just otherwise play.

Andrew Davies site at

http://www.taswegian.com/MOSCOW/soviet.html

also has good information.

[Ralf Fritzsch]

I bought a MK 54 about 20 years ago when I studied Mathematics in St. Peterburg (former Leningrad). It was not my first programmable, and not my last. But in that time it was a really mighty tool for me. I've made up a large compilation of programs, the most versatile of them was a 12 point Fourier Analysis program, which is not bad for 98 steps, and 15 registers.

But there were four main disadvantages:

1) Very bad, unreadable green display
2) volatile memory
3) Sloooooow speed
4) really bad precision, e.g. 3^2=8.9999984

Thanks God today I have some of the best HP calcs at hand (12C, 15C, 41CV, 32S, 32SII, 48G+, 49G), but nevertheless from time to time I take a glance at my old friend MK 54 ;-)

[Namir]

Thanks for the link. It points to some interesting information!

[GE (France)]

Obviously these programs would be of major interest to many MK users. If you ever type them out...

Maybe you unterstand russian and could translate the manual ? I know it's easy to assign work to others (my boss is doing it all the time), so if you can send me something readable, I may be able to help.

I only have a 52, a 61 and a 90, all obtained thanks to Andrew Davie, a very excellent example of friendly and helpful person. Too bad they are not for sale, sorry.

[Ralf Fritzsch]

GE (France) wrote:

>Obviously these programs would be of major interest to many MK users. If you ever type them out...
>Maybe you unterstand russian and could translate the manual ? ...

Unfortunately, all of them is gone. IIRC, I donated my program compilation to a fellow student with a B3-34, and the manual disappeared before 1985. :-((

But try to search the web, there are lot of ressources regarding former soviet calculators, maybe even in English.