EEVblog #482 - Retro Iskra Multimeter Teardown

[ivan747]

Wow, there's a lot of love in these soviet (am I right, maybe ex-soviet?) multimeters! I don't really appreciate this kind of construction and I hate even more the 50's TV construction but I can see this equipment has a good fanbase.

[Hankus]

Dave, I'd like to see you repair the failed current range of this meter.   

[Bored@Work]

these soviet (am I right, maybe ex-soviet?)

No, wrong on both counts

Soviet = worker's council; Soviet Union = Union of Soviet Socialist Republics = USSR = CCCP

SFR Yugoslavia = Federation of six socialistic states plus some autonomous provinces != USSR

Communist country, but not part of the USSR, not even part of the Warsaw Pact. I fact had a kind of fall-out after WWII with the USSR and was for a few years even thrown out of international communist organization. A few years later they cuddled up a bit again.

Broke up in a series of bloody wars starting in 1991, parts of the disputes still going on, e.g. about international recognition.

[Stonent]

I guess I learned something today too. I had always thought Yugoslavia was part of the Soviet Union as well.

The Federal People's Republic of Yugoslavia is sometimes referred to as a Soviet satellite,[6][7] though it broke from the Soviet Union in the 1948 Tito-Stalin split, with the Cominform offices being moved from Belgrade to Bucharest, and subsequently initiated formation of the Non-Aligned Movement. The People's Republic of Albania, under the leadership of Stalinist Enver Hoxha, broke ties with the Soviet Union in 1960 following the Soviet de-stalinization process.[10] These countries were, at least between 1945 and 1948, all members of the Eastern Bloc.

So now I will always know Yugoslavia for their hand crafted multimeters, and luxury automobiles! 

[Hydrawerk]

I have a Metra PU120 multimeter. It's quite accurate and easy to use. It's compatible with today's banana plugs. When you insert AA cells, you can even measure transistors and resistors. It was made in Czechoslovakia. Sometimes i use it.
My father bought this multimeter probably in about 1975 or so. But here they say that it was introduced in 1967. http://www.radiomuseum.org/r/metra_blan_multimeter_pu_120.html

[Hydrawerk]

 

[Hydrawerk]

And I even have a strange multimeter ?4323 made in USSR in 1977. It has weird, non-compatible banana plugs. I don't use it much, because it's not much accurate and it has weird scales. It has built in signal generator!! It's powered by a weird 3V battery of type 224. You cannot buy it nowadays, but they were at markets in mid 1990s.

[Hydrawerk]

  Note the weird thin plugs. There is a standard banana plug for comparison.

[c4757p]

Is the English text "MADE IN USSR" common?

[Hydrawerk]

Maybe it was for export. Here is schematic.

[free_electron]

I say grind it down to bits so they can be recycled into modern technology.

[big9swimmer]

I preffer the look of LED over LCD regardless of power conumption. Dont destroy that meter if its working, it is history to me. Far as gettin in there to see, Dave I would recomend looking into a automotive Boroscope. Could slip that right in between those bourds and get all the shots ya need.

[Hydrawerk]

Well, most bench top multimeters with 230V power supply have some kind of shining display, LED or VFD.

[Neilm]

I work for a company that still sells electronic equipment that was designed in the 80's, about 84 from memory (at least I think it is still in production - certainly was 2 years ago).  Never been obsoleted cos it simply isn't worth designing a new one. It has a couple of board in it and a proper wiring loom built on a pin board to get all the connectors and branches in the correct place.

Neil

[shashwatratan]

Beauty 
     
Don't take it further apart!

[bitwelder]

I'd be interested to know how much that model of Iskra was costing in the '80, and compared to the salary/income of a electronics technician.

BTW: I'm also on the "beauty! don't take it apart"-camp.

[Hydrawerk]

Digital electronics was bloody expensive in communist countries in 1980s.

[xrunner]

Beauty 
     
Don't take it further apart!

I bet some collector or museum would kill for that Iskra.

[sdttn]

It shows 3,14 (PI) when it is over loading. Why?

[c4757p]

That just happens to be the highest it can count to, I'd assume. Once the counter throws the overflow flag it displays the number as usual and starts blinking.

[ashplant]

Good video.

I agree with your "Design for manufacture. What's that?" This old Iskra multimeter is almost like a very good hobby build.  Do you have any idea how big the production run was? 

[Stonent]

It shows 3,14 (PI) when it is over loading. Why?

I caught that as well!

[McPascal]

I think that multimeter is beautiful for its age. I would repair, and calibrate it in another video! 

[Dave]

It shows 3,14 (PI) when it is over loading. Why?

Nope, not pi. The meter shows 3.144 or 3.145, while pi is about 3.14159265358979323846264338327950... so rounded to 3.142.
That number is probably the maximum value the ADC can read.

[TheWelly888]

I can see that if Our Dave has to figure out what is wrong with the current ranges, he may have to dismantle the boards in order to fix it but I don't think it worth the effort.

But I'm with the others here, don't destroy that meter!