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- Опубликовано: 15 окт 2024
- What's inside a 1980 vintage Yugoslavian digital multimeter, the Digimer 10 from Iskra
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Crusty? No way. That thing is pure beauty. It makes the magic of electronics actually look magical.
Hello Dave and everyone else. I am from Croatia, country that was a part of former Yugoslavia which broke apart in 1991. I am also an electronics engineer, and I like to watch your RUclips videos. Well, very very nice digital multimeter there. There were 3 main companies in Yugoslavia that produced electronic components and devices: Iskra, RIZ and EI Niš. Iskra is from Slovenia, RIZ (radio industry Zagreb, I see few components from RIZ in this multimeter) is from Croatia and EI Niš (electronic industry Niš) was from Serbia (I don't know if this company exists any more). Iskra was the leader in instrumentation, RIZ was leader in electronic components, and EI Niš was doing a little bit of everything but mostly developing and making TV and radio sets. So you say this multimeter is not built so well for the 1980's. I must agree with you, although it hurts me to say that. Yugoslavia was a communist country where technology from west wasn't so welcomed because of the leading man named Josip Broz Tito. He thought that our technology was developed good enough to make anything we wanted. So we did, but it looked like this multimeter. Till the 90's, almost no electronic device used microprocessor, everything was developed using only digital logic and analog circuits. Companies that made electronic components didn't make custom chips for anybody so you had to deal with regular chips to develop what you had in mind. In that case, every device was big and "bodgy" like you say. Although every instrument, TV, radio, production automation electronics and many other devices were made so bodgy and,... well I will say ugly, they WORKED and they worked great. Because of its robust construction, they were also very easy to fix. This technology couldn't keep up with microprocessor devices so we had to begin using western electronic components and microprocessors. But, I will always remember the simplicity of Yugoslavian made devices. This also applies to cars that were made by Zastava from Serbia. You all probably heard about "Yugo", a car that never succeeded in USA, but in Yugoslavia and then in all these countries after Yugoslavia crashed, it was one of the best cars. It was simple, it used old technologies, but it WORKED great, and it was easy and cheap to fix. So many of them are still on the roads in all former Yugoslavia countries, just like many production lines in many factories still use that old non microprocessor automation technology. And yes "Iskra" means spark :). Best wishes there, sory on this long text.
JJ electronics bought the tube division of the former EI company and still manufacture one of the best new tubes one can get for a good price :)
+Davor Pavošević Prijatelju, dobro si to napisao :)
Former Yugoslavia had (for it's times) very advanced electronic manufacturing capabilities. And as you said, it was robust, but it worked. The comparison between Iskra's multimeter and that Fluke is silly, obviously the Fluke was one low cost crap. Iskra has FR4 boards and all is gold plated. And it still works.
Yugoslavia was an interesting country. As far as electronics is concirned, almost everything was made here (I'm from Slovenia). From resistors, to various sorts of capacitors, transistors and even custom ICs. All together was suficcient to make almost any electronic equipment for those days.
I still have some of that metal BC108A transistors, some SMD capacitors and stuff. I just can'tr throw it away...
Iskra had many interesting capabilities and technologies. For example Samsung and Goldstar TVs from South Korea used foil capacitors from iskra. The factory is very near me. Also, when I was a kid in primary school, we got a trip to Iskra multilayer capacitors factory in Žužemberk. At that time I first saw SMD capacitors, but I didn't realize their potential yet. Electrolytic capacitor factory was in Mokronog and semiconductors were mad in the capital Ljubljana. Iskra HYB is still making some advanced hybrid modules...
Davor, I don't know much about RIZ, I know, they were manufacturing transistors (I stil lhave some:) but anything else...
Thank you Dave for your teardown of multimeter, I couldn't afford at that time :)
Peace & love to all.
+MacedoniaGamingNetwork - MGN Haha, I hope you are wrong, but I don't know. It's hard to beleive anything theese days... Sve najbolje i u Makedoniu :)
Srečko Lavrič I really hope your country is comming back to full power again, someday!
+TubiCal Thanks for your good wishes. It isn't so bad at all, but it could be better. Corruption is one big problem here. But I guess, that we are not alone :) Peace to all.
Thanks for this beautiful teardown. What a beast! A piece of history. I get the feeling that life was better back then.
+Tobias Påhlsson In a way it was... Many people have good memories for those times, me too. On the other hand, we were very restricted and also there was no eBay or Aliexpress back then.
Iskra from Slovenija Now produces the most effective electronic engines and other high-tech products
Its a beauty and she is stil working. The other multi meter does not even work anymore and is full repairs. Love stuf like this.
In contrast to the Soar I found the Iskra to be quite unique in design approach, and more importantly; Serviceable. There are also multiple calibration pots across the unit, presumably for every measurement type. You could easily calibrate the unit and put it into faithful service rivaling half your 'current' bench meters, 30 years after it's birth. The engineer should be proud and that was quite a gift you got there. Thanks for the vid!
Thanks for the offer. I don't do a huge amount of rework stuff, but that alloy would always come in handy, so by all means, send some through. Thanks.
My first multimeter was an Iskra. Newer model than that, it was also analog. But it worked great. And the easy access to replace the fuses was a really nice feature. I wish I still had it. They were much better built later on.
"Iskra" means "spark" though...
Everyone I know here have a handmade screwdriver for those nasty screws. At a job, there are still some Unimer 45 and 43 in usage, and 7045. I still have some leftovers from two Unimer 1. Still having Unimer 33, for proper phase sequencing. These are easy to repair, hard to blow. Anyone that had some of these instruments, kept them until they fallen apart. Iskra has a great tradition in measuring instruments.
Best Regards, from Serbia.
Thanks Dave and donor! This is great! Old stuff just a kick! My oldest multi ? Tube tester is a Jewell so few tubes back when made it tests in circuit was a real challenge I could not identify half the parts but got to work. Worke great restoring an E.H.Scott keep up the great work
I think it's a thing of beauty! One of the reasons why I got into electronics is because I tore apart Eastern block gear as a kid, and was blown away by the colourful components, wires and crazily constructed/sandwiched boards. I desperately wanted to know what these shiny little bits and pieces were. And for these reasons, my favourite looking components are still tantalums to this day.
Jeez, this takes me back :)
For what it's worth, Iskra was electronics equipment manufacturer in Slovenia, which was then part of Yugoslavia. IT STILL EXISTS. They used to make pretty decent stuff in those days, their power tools were ok. The gold standard in those days was Bosch tools, or if you had a lot of money - AEG. Iskra wasn't on par with them, of course, but it was usable, cheap and easy to get parts for. Chinese crap didn't exist back then.
Man, what a blast from the past :)
As "bodgy" as this multimeter is built, it looks to me like they were following some sort of conventions in it's design, bodgy conventions, perhaps, but it's one of the nicest examples I've seen of point to point/pcb hybrid building from that era, plus all the soldering is top notch.
I suspect this unit cost fetched a lot of money when it was new, so treasure it, it's an awesome piece of tech, much better than most today imo. Probably a museum quality piece in reality
Eastern Bloc had very limited resources as far as electronics went. Very hard to get hands on latest Western tech, limited opportunities for in-house development. So you made it work with what you had. I serviced a lot of AV tech from Poland and Czechoslovakia and they looked dodgy right from the factory, just because of hand soldering and hand assembly by people that faked theyr work efficiency. It worked but if you take off your nostalgia glasses, quality was on par with something like Ferguson Electronics or Amstrad. There was no need for high-end stuff, nobody could afford it anyway, workforce was cheap, USSR market bought anything so why even bother?
Amazing it still (mostly) works! Work of art.
Even nowdays when you ask someone in ex-yugoslav republics for measuring instrument you ask for "UNIMER" (not DIGIMER) and they will know immediately what you ask for. That alone pretty much tell you what ISKRA meant back in the 80's. GREAT Video BTW.
I found the switch arrangement quite ingenious. It's not easy to design mechanical cams and latching springs.
Thanks for the teardown, Dave. There is no need to take it apart any further from that.
Looks pretty nifty, it has a better range for current than my Fluke 115!
This is incredible. Loved the 555 timer used for the PWM of the LED display.
Best tear down subject matter seen recently! Great stuff. Love vintage electronics. That construction is great! Beautiful ugliness!
Thanks for yet another awesome, entertaining and instructional video!
Would love to see a repair video of the Amps range!
back in the eastern-block they build their equipment to last. my old (and I mean older than myself) east-german scope looks like i could bludgeon somebody with it and it still works perfectly after all these years. And the manual also includes these coded resistor-symbols. I vaguely remember having paid more for a set of probes than for this sucker.
I agree. Actually this thing looks fairly bombproof and reliable. The circuit board everyone is making fun of looks like it minimized parasitics better than a modern one. How many affordable DMM's have a 2Kv range? I really like this meter, if I ever see one, I will grab it. LED is a plus in my book. Only thing I don't like is the tantalum caps. BTW, had a Yugoslavian milling machine, it was awesome, liked it better than a Bridgeport. Is that cool screw-in fuse blown?
Way to go Janez. I am from Serbia but nevemind that. You made some really quality stuff that works to this day. :)
Oh man, I still have one of these. Iskra was a huge thing back in Yugoslavia, one of their divisions even landed a multimillion dollar contract with the Chinese CP to install a massive network of connecting some of the major police precintcs back in the late 1970s/early 1980s.
I'm in the 'it's not bodgy' camp. It looks like a wonderful, durable, heavy-duty hybrid of point-to-point and PCB construction. Pretty common for the era I think, based on what I've seen. It looks iffy, but I'd bet money it'll work forever.
what a lovely display, too!
Yeah, Iskra was great! I have two analog multimeters of theirs and they still work great! I have changed a dozen probes which were worn out, but the multimeters work like a dream. Iskra made good quality gear.
I work for Iskra yay. Down in our workshop there are tons uppon tons of oldshool parts which i could mail to you if i find the time =D
i buy them, i repair old electronics among building new stuff, i much prefer genuine old components for repairs.
:) How did this one come to instrument Australlia? They used metal transistors probably because they were made in RIZ, Zagreb - home made stuff. My dad worked in RIZ on radio-interference and TV, and my friend's mom on theese transistors and other semiconductors. They were done with microscopes and it was a quite a hard job. By the way when I'm talking of transistors, I'm just improving on my power suply and I found some 2N3055's of the firm called "Tesla" that they put in TV's here in Croatia. Theese are called KD3055 and I don't know what they have done to them but theese I (accidently) overheated when I was a kid and I was able to melt solder wire on them for hours and they still work. Then I figured, if this no-name transistor can do that, all of them can, but not nearly, they short E to C at around 200C. That's how I misdesigned heatsinks for 2N3055's.
...instrument Australia, i meant, this instrument come to Australia
This is my friend made to work 100 years.
Yeah, dip tantalums kinda have a funky look to them.
I sure wouldn't desolder the connecting boards just to be able to further inspect the electronics. This meter is in fantastic shape and if it were me I would leave it intact.
I love these old 1980's meters and to have one in this condition that works properly is really great. Funny thing about these meters is I tend to get far more use out of my cheap Radio Shack multi-meter than I do my Fluke 87! I love the quality and accuracy of my Fluke but I always use the Radio Shack for most projects!
If you compare two multimeters interiors then you should also compare technical specifications. I bet Iskra kicks our old multimeters in every spec.
Iskra multimeters (and other laboratory equipment) are still quite useful and very accurate.
Anything they made is superb. Maybe not as "clean looking" as some would prefer but it's virtually indestructible.
(Slovenci su zakon samo tako...)
Ah, I have that one. I also have some color-matching add-on plug-in modules for capacity measurement, transistor ID, etc., but apparently not made for this Unimer model...
I had Iskra Unimer 3 and Unimer 33 analog multimeters. Later models are the same as Gossen Metrawatt analog meters. I think iskra was making meters for Gossen.
Latest Iskra multimeter made in late 19xx was one of the best analog meters I have seen. It was very accurate and made to last 30 years .
Love your teardowns. Especially of the vintage stuff. Such a good way to kill time as they are quite long. I now often find myself taking everything apart.
The circuitry and all components certainly appear to be good quality. It was an amazing feat of engineering to fit populated circuitry together like this, especially back when thru-hole components were the standard (pre SMT). When I started with General Dynamics in the early 1990's we were just getting ready to begin testing SMT populated circuit boards and boy what a space saver that was. We could fit ten times the amount of electronics in a given space as we did using thru-hole components!
It's nothing yet. You should seen our DIGIMER 1 with glow wire display. Or our WORLD's first digital oscilloscope with LCD display.
No need to defend this tech, we don't often see stuff like this so it's totally fascinating to us. The laughter is more from surprise than disdain, and it makes very interesting comparisons. Love the use of washing machine tech in this device too !
Some funky swirly looking tracks on the PCB!
They almost look like they are drawn on by hand :)
Very nice!
I believe the multiple trim pots are because the tolerance of resistors from Eastern Block countries before the break up of the Soviet Union were notoriously poor. I find it amazing how you have to turn two different knobs AND plug the probe into different jacks for a particular function. Weird!
Iskra is a Slovenian company :)
a odakle je slovenia u to vreme bila hehhe
E kada je Yugoslavija pravila ove multimetre Australija nije ni znala sta je to.
evo sedim tu
@@pedjarudnikpcservis ziva istina ;)
33 years old, and mostly works and still in spec? Bodged or not that is fairly impressive. Especially for a solution that is running from multiple internal voltages with switched DC-DC conversion. My Wavetec 27XT from ~20 years ago doesn't have specs that are much better.
Arcade monitor chassis schematics have those different resistor/capacitor keys like you commented. Can make looking at the schemes a bit confusing sometimes.
Love the vintage stuff. What a great piece of history!
When Tito died, it was a sad day for South-West part of Romania - we respected and loved Tito. Not a North Korean kind of "love" - we considered Tito a wise man and a very good military tactician. He protected his people from a wild version of communism and he allowed them to have some sort of small business... we weren't allowed to have that.
The meter might have junky construction, but it had good specs for its time, continued to work for 33 years, and held its cal for that time. Impressive.
I've actually got one of the old Gossen Metrawatt multimeters with the exact same chipset. I really love it e en though the 200mA range is currently broken. I am also working on retrofitting it with USB, that will be fun!
I mentioned that the DMM project in Popular Electronics in Deceber 1974 used the same 2-chip A/D converter, but I should add that they did not rip off the design. This has more ranges, the power supply is different (even though they both use NiCads), and it's different in general.
BIG RESPECT AND HELLOO FROM MONTENEGRO EX JUGOSLAVIJA ;)
ISKRA Components were quite good, served me well anyway.
They made some TV's which were quite good stuff.
Thank's for the Vid.
Nice classic multimeter. Same age as I am.
I think is a good ideea to keep that multimeter as a colection piece.
Best regards from Romania. :)
You are true in theory, but as I can remember there was big difference between components "officially" produced and components really available for amateur use. I had 5 red LEDs in 1986 which i desoldered from old circuits and soldered into new circuits over and over again (in Czech republic)
Did you build any 555 circuit in Honecker era ?
Loving the posts Dave - Keep up the good work, but for pitty sake the wife wondered what I was watching when you said this (27:54) "My knob fell off... oi tada... Ergh"...
This multimeter looks like it's been cobbled together with whatever parts they could find in the rummage bins at the factory, with the wiring modified to match.
Wow, that is beautiful.. Love the traces 'art'..
Different resistor types are marked because of different tolerances, so that person servicing it could get the tolerances right on a part replacing, since this is measuring equipment after all.
By the way, what about that little bag-of-old-russian-electronic-components that was in the package with this multimeter? Did you find something interesting in there?
Dave, the power consumption is there in the manual, it says "1 VA" @4:53
Looks like that multimeter is more or less exactly the same age as I am! My production date is 07/80, too!
Yes, feedback looks really bad! Please explain...
This is made in Slovenia to be exact. The company that made that multimeter still exist u can google it out.
The part of Iskra that made measuring instruments is called Metrel today.
Part of Iskra renamed to Letrika now and thay make electric motors, alternators and lots of other stuff like starters for John Deere tractors.
google "intersil LD110", I found a Siliconix pdf with sample circuit (pag 7). In there they use a 2N4274 NPN transistor as a reference, same as this DMM has.
Vref input to LD111 is pin 9.
could you do a repair video for this unit?
thank you for another GREAT teardown :)
Actually, here in the Netherlands we have Iskra smart meters. I also have seen big DC motors (garage car lifts) from them.
Heh, if you can ever do a review of a Fluke 45 bench multimeter...
That looked really neat, thanks for the teardown !
Do you have any idea why the current range didn't work, could it be that the tantalum caps have gone bad ?
As for taking the whole thing apart, only if you fix it as well :)
Nemoz da veruje da je ovo doslo iz Yugoslavije. A cuo li si za Nikolu Teslu mozda?
2:53 I see nothing wrong with that depiction of wirewound resistors. It's not the current way to do things, but it made sense to me.
10:00 that may be more complex that you expected...
heh, LCD (:
I love these reviews of old technology :o) It would be interesting to see a video giving your opinions of how electrical technology will evolve in the next 30 years :o)
Yes, but this one was per 10K/C, not the more usual 1K/C
Great! I love such vintage electronics.
It looks to be very good engineering, still very precise and reliably. Please do not destroy this rare piece of technology and history.
Thats a work of art
:) No offense taken on my part. It wasn't done in a cave or anything like that, but the time was different. We were not copying everything left and right. Our engineers developed a lot of things on their own, and some parts were just not available.
Google up Iskra Yugoslavia factory photos. Not PRVA ISKRA, just ISKRA. :)
Do digital multimeters use ADC ? If so what's the reference voltage to measure the battery voltage ?
july 1980, I was 5. I wish manufacturers now days would provide the same documentation that this meter has .
I'm wondering if some day somebody will send you a thing with logo "Unitra" :) That will be from my country
i'm waiting for that moment too :)
I love it. I wonder how much would it cost, well, or how affordable was it.
Hmmm seems to follow the same more or less mux'd sample and hold layout that I've seen go way back to the nixie benchtop era meters before the 7106/7 IC's became ubiquitous - almost like it was several years behind the then state of the art.
iskra means spark...
Iskra is big in netherlands with it high standard electrical smart meters.
So must a cheap and good compagny and great value for it money
What's the deal with the diode Z101 at time stamp 2:23 just at the screwdriver tip? It goes to nowhere? Hmmmm.
I completely agree with you. I believe the beginners should start with analog design. Even the digital design and construction skills are more and more weaker. Arduino, Pie etc. are good but they are not encouraging begins to build and design new stuff.
As a Romanian (their neighbor), I always envied Yugoslavians for their very permissive communism. We constructed special TV antennas (and special amplifiers) to receive their TV channels and loved very much (and we were drooling at the sight of) their advertising for the various kitchen recipes :P (and so many "occidental" movies). Tito was a wise leader, but Yugo started to fell apart at his death (even if the 4? leaders followed his last advices regarding to succession)...
did you break the uA setting when you overloaded the mV setting maybe?
I like this meter way more than others. Where the designer had parts available these guys has to think. This is a workaround and it's pretty damn good considering it was probably done in a cave with rocks and stones *no offense intended to the former Yugoslavian citizens*. Also between tech like this and tech from current age, i prefer this one because you can at least change parts and improve on it, the new ones might look slick and have form factor but if the main chip leaves it's done.
I like old electronics :)
There is not much fun looking at something where everything is done in the same microchip... :)
Wait, did Dave just stop taking it apart... to turn it on?
Translation from Serbo-Croatian:
It isn't from croatia... It was built in the Socialist Republic of Slovenia, as part SFRJ.No need for the appropriation, the entire former Yugoslavia had a solid electronics industry:Riz, Rudi Cajavec, Electronic Industry of Nis. However, the two most recognized electronics engineering faculty were and still are in ... Belgrade and Zagreb
@EEVblog is the LD110 CJ manufactured in India? :O do you see that often?
Intersil does have a plant in India. intersilindia.com/
"Intersil (India) Pvt. Ltd. was established in 1979 as a technical and financial collaboration between the Mehra family and General Electric for assembly and test of semiconductor devices. The company diversified into software services and real estate since its inception."
Then it was Westeren block and Eastern block and "Unaligned movement" established in Belgrade Yugoslavia in 1961. Remember Tito, Nehru and Naser? They were masterminds behind that organisation. It had 120 member and 17 observer countryes. For instance India, Egypt, Cuba, etc. And Yugoslavia was doing business with most of them. A lot of military equipment, and a lot of industrial equipment. Turbines for hidropower plants were made in Litostroj (Ljubljana, Slovenia) for India, Egypt, etc. (My farher worked there as an engineer.) But Iskra was BIG PLAYER in this business. They (for instance) provided electrification of Turkish railway for instance using German standards. So big westeren companyes cooperated with Iskra to get acces to Unalignedt movement countryes markets. Civil and military as well. It was HUGE market. Siemens cooperated with Iskra railway equipment. DEC was seling their mainframe computers throu Iskra Delta even to Rusia. Just type "Iskra Phone" in Google ... yes, that phone was designed and built by Iskra. Great success. And it was masively copyed by westeren companyes. I was working with the industrial designer that created that phone. We called it "Fitipaldi" here in Ljubljana/Slovenia. Other HUGE business of Iskra were Power meters. Were and still are. If I'm not mistaken, they cooperated also with Siemens, but continued on their own. Not to forget Iskra Electro Optics (now Fotona). Laser targeting and navigation systems for artilery and rockets were developed for and with Israely military. So. This Multimer is not suprisingly built as it is. For all that industry, they needed "quite a few" of them. The price was not a problem. Afterall Iskra was employing a lot of workers just for soldering such electronics. There was not a problem to produce small series, as well as masive production like "Fitipaldi" phone. All (practically) hand crafted. They didn't have to mind the price so much. Oh; and why is that chip from India? Another mayor Unaligned Movement country.
When it is over loading it shows 3,14. Is this PI?
You were welcome for "stealing" our tv signal. :))) Its similar to wifi nowdays. :D
Yay It's up! Waiting for this! Thanks
Did anyone found out what kind voltage reference that meter is using? Anything in the teardown or schematics?