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Күн бұрын

Teardown Tuesday.
What's inside a 1980's vintage 8.5 digit multimeter, the 6047 from Prema. Or did Dave diddle himself?
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Пікірлер: 100

@mikeselectricstuff 10 жыл бұрын

I'd guess that "1041" serial no is actually 41 for something this obscure. Quite common to pad out small serial numbers.

@robertw1871 5 жыл бұрын

The only down side to a super high resolution meter is the $2,500.00 they charge to calibrate one, having that done twice a year adds up fast... it looks to me like that thing was built on a bench one by one and tweaked a lot, probably took days to make one, almost like each one was a prototype and the parts were played with empirically to get it just right...

@electronicsNmore 10 жыл бұрын

Great video. Yes the diode, and resistors that appear to be repaired from the top side of the board are not to perfection, but I have serious doubts that those repairs would ever pose a problem. I have seen a lot worse that lasted many years.

@xDevscom_EE 10 жыл бұрын

And sorry to correct you, but it's 7.5 DMM. Only 6048 is 8.5. So keep working to get a proper volt-nut gear. :) And I keep mine EDC 24/7 live.

@Pillowcase 10 жыл бұрын

what a gorgeous piece of vintage equipment... i love the digits integrated into the key panel

@hannonm 10 жыл бұрын

Love how all the IC's are in sockets. easy to replace

@VolksTrieb 10 жыл бұрын

Isabellenhütte is like 10 miles from here ^^ They do low coefficient wireresistors :)

@jusb1066 10 жыл бұрын

considering you bought it from the UK and he only charged 19,99 delivery, it arrived in one piece! well done the post office

@kleinerbub84 10 жыл бұрын

PREMA operates from the city where I live, never heard of them before! Crazy!

@Archer198026 10 жыл бұрын

Isabellenhütte is a company founded in 1482 in Dillenburg, Germany. They are specialized in precision and high-load resistors. And they co-developed Manganin, an alloy for high-precision resistors.

@Archer198026 2 жыл бұрын

@Shanae Wow, an answer after seven years. Apparently the company started as copper smeltery

@SantaClaw 10 жыл бұрын

I see the board in the middle was marked as 6048 - I - 5 and the left from the front is also marked as 6048 - M - 2 And the right one, the one under the shield marked as 6048 - V - 5 I wonder what makes it a 6047... I guess they just used the same boards, just different components ?

@thatguyb3rt 10 жыл бұрын

Either that or 6048 is just the part number for the board assembly signifying all of them, I'm not an expert on this stuff though so I couldn't tell you for sure.

@aserta 10 жыл бұрын

I buy quite a few things on Ebay. But one thing i do is i always communicate with the seller to ensure good packaging. Never got anything damaged. In parting : Nobody wants a negative and if you don't ensure they do it right they won't.

@compactc9 10 жыл бұрын

I tend not to even try to hide my horror when something happens like the employee tossing the meter down on the counter. I'd have probably involuntarily gasped and had a look of horror on my face.

@compactc9 10 жыл бұрын

I prefer either a about 5+ inches of bubble wrap or lots of foam peanuts. Lots of people hate the peanuts but I love them, they are great packaging!

@ovalwingnut 4 жыл бұрын

Really intriguing. And yes, I was surprised to see such a "casual layout" considering its pedigree. I like it no matter. But then again I like weird chit. Thanks so much Ausi Man ❤

@zaprodk 10 жыл бұрын

Better take a backup of that Eprom! - Also, It looks like the front mounted fuse holder is not connected in series with the terminals ?!

@gglovato 10 жыл бұрын

yeah i saw that, it looks like only ONE cable is soldered!, Dave?

@NathanaelNewton 10 жыл бұрын

"thermally bonded transistors, they're in love" Oh man.. That made me laugh ahahah... XD Awesome video as usual :D

@KX36 10 жыл бұрын

I love thermally bonded transistors. My Philips PM3217 is full of them, being all discrete transistors. :) Also KOAX!!!

@redtails 10 жыл бұрын

2:50 hope the postal service didn't ruin it.. though for this reason (and for chance of the thing getting lost), it's a small effort to send stuff insured.. Where I live, I send anything over 100€ of value ensured because otherwise it's just too risky of getting lost or damaged. Of course with gear like this, you're only going to get back your eBay bidding or costs, and not the full value of the machine

@hinz1 10 жыл бұрын

Did cost 613 USD on ebay.uk, if that's the one (the dirt on the display and below the power button is the same, as is the black stuff under the mADC button). Quite cheap compared to the HP3458A, but the 3456A is a magnitute cheaper and with 2ppm still more thanb enough for me

@tfhAlex94 10 жыл бұрын

Isabellenhütte is german company very well known for high current shunts with low temperature drift.

@thenewtrilogy2 10 жыл бұрын

yo, ya description says, that its an 8,5 digit multimeter, but we already found out, that it is a 7,5 digit multimeter :)

@Toble_Miner 10 жыл бұрын

The packaging is almost as bad as the Amazon packaging for HDDs back in 2012.

@smbrob 10 жыл бұрын

I don't think it looks to bad for the time it was put together. Also the fact that is is still quite accurate is impressive :-) Can you tell me what this state of the art meter would have put you back in the old days ????

@sprybug 10 жыл бұрын

I hear you about buying stuff off of Ebay. Most people package the stuff they sell like shit. I'm surprised I get things in working order most of the time. Whenever I sell on ebay I always make sure I well pack what I sell so that it gets there in the same condition that I sent it.

@FunnyHacks 10 жыл бұрын

Are there functionality differences between the 6047 and 6048? I was thinking about the extra circuitry and thinking about how as a company selling these, you don't want people to say "Well if you change 2 $5 capacitors, you can have the extra accuracy and save yourself $500!"

@EEVblog 10 жыл бұрын

Yes, the 6048 uses the LTC reference and different circuit to drive it. They would have to characterise this part better.

@murnelbabineaux105 7 жыл бұрын

Why is that so critical when most electronic circuits are +/-20 percent ?

@winstonsmith478 10 жыл бұрын

After seeing the caps across the resistors on the board under the shield, perhaps what look like repairs elsewhere were actually due to a manufacturer field mod?

@SarahWattCA 10 жыл бұрын

I'm really hoping that those poorly-soldered components were part of a third-party repair job because if I soldered anything that bad I'd be embarrassed even if I WASN'T selling it.

@SudosFTW 10 жыл бұрын

typical 80s Dallas clock chips. Hate them SO much. especially cutting into them to solder a new battery holder with battery in so to continue using the same Dallas chip.

@devjock 10 жыл бұрын

It's all about that german efficiency apparently. They don't mess around with doing it all beautiful. It works. and that's what matters. I love it!

@ratdude747 10 жыл бұрын

I hate how ebay reviews ask for shipping charge accuracy but there's nothing on packaging quality. I have a buddy who was screwed over on an LCD that way... some hilljack packed it in pop can boxes for padding... Some pack it well, some are hopeless!

@EEVblog 10 жыл бұрын

Some sellers do go to an effort to show and explain their packing procedures (e.g. vacuum form packing), but it's not many.

@larryrussell5440 10 жыл бұрын

I always comment on the packaging in the written feedback.

@joeharrison7279 7 жыл бұрын

Larry Bola

@onwul 10 жыл бұрын

Dave mentioned couple things being bodgy. I'm wondering, if you go in and fix all those bodgy stuff and replace some of the stuff with perhaps more precise/stable/better alternatives what appeared today, will it make multimeter more precise and stable? And is it worth the trouble?

@mausball 10 жыл бұрын

Looking at the construction, I'm guessing it's serial 41, not 1041. No one has ever padded low serial numbers before, have they? ;-)

@EEVblog 10 жыл бұрын

I've seen things worse than this manufactured in the thousands, nothing new there.

@MrRexquando 10 жыл бұрын

I can't share my love of this video with my friends :( Kind of like a great video on a moped. A lot of fun until your friends see you riding it.

@knssoftware6018 7 жыл бұрын

i know, moped / fat chick... you don't want be seen on one! we all need a guilty pleasure, even if it is Dave!

@natsumiyuki9173 10 жыл бұрын

With your skill sets you should upgrade it and fix the bodging and show us a before and after!?

@lean04 10 жыл бұрын

could you add the circuitry needed and upgrade to a 6048? (like you always say may be not worth the time, but...).

@rustyrebar9647 4 жыл бұрын

That's not cardboard, it's called fish paper! 31:00 An lm299 in a 7.5 digit meter?

@PuchMaxi 10 жыл бұрын

Dave since you are a big fan of Sinclair, and vintage multimeters. Do you already have a Sinclair DM2 Digital Multimeter? Nice to add to your multimeter hoard/collection! ;-)

@douro20 10 жыл бұрын

Precision Monolithics OP42-FZ op amp in there...

@chrisbaker21 10 жыл бұрын

Where can I get a KOAX t-shirt? Should we submit designs on the EEVBlog forums?

@darrenjacobson7456 10 жыл бұрын

Being that it's still 7.5 digit, is it actually better than your agilent meter? Also, you've said in the past that to calibrate something you need a reference with at least one order of magnitude better resolution. Having said that, could you calibrate a 6047 using a 6048 (already calibrated)?

@XOIIOXOIIO 10 жыл бұрын

"You know what we say on the eevblog, don't take it apart, turn it on!" Hmm, not quite as catchy. Awesome find though, that would certainly be handy.

@MiggyManMike 10 жыл бұрын

Tuesday ended 25 mins ago here :p

@PokemonGlitches123 10 жыл бұрын

hehe i guess youre probably in britain too :P

@MiggyManMike 10 жыл бұрын

Indeed :D

@FooBar89 6 жыл бұрын

hand picked? that makes sense for resistors and cheap components, but for a voltage reference? what do you do with the ones that don't meet the criteria? throw away? that doesn't make sense, those are not cheap

@absurdengineering 5 жыл бұрын

ThinkLearnSolve You could use them in a lower spec product. Of course you can’t use them in your primary product - it’d make it out of spec. That’s why you select them.

@TheDutyPaid 10 жыл бұрын

Thing is with Ebay and selling things, packaging cost extra money on the P&P that no one will pay for when other people pack items like the one Dave got for less cost then I fully protected item. Plus PayPal taking their money which is from the total cost so the money the seller has to send items is even less. I have sold items on Ebay and ended out of pocket because of the postage costs with the low sell price the item reached.

@hans429 5 жыл бұрын

Is your toung right and your Angle is wrong, or ist the toung wrong and your Angle is right?

@ronniezzzz 9 жыл бұрын

strange resistors dave

@frostfirei 10 жыл бұрын

I never buy anything on E-Bay, unless it comes with a guarantee, unless labeled As Is!

@redtails 10 жыл бұрын

12:33 XD always the smelling

@redtails 10 жыл бұрын

15:21 well it certainly isn't shock proof!

@Jellow2202 10 жыл бұрын

The single-in-line shut resistor you found in there is made by a German company Isabellenhütte (www.isabellenhuette.de/en/precision-and-power-resistors/) which produces custom resistors. I found the specs for their trademarked material "Zeranin® 30", but I don't know if it's the same as used in there because it's missing the 30 on the package: www.isabellenhuette.de/fileadmin/content/widerstandslegierungen/ZERANIN-ISABELLENHUETTE-R.pdf

@bborkzilla 10 жыл бұрын

Those buggers are expensive to get properly calibrated.

@EEVblog 10 жыл бұрын

For sure! This is essentially a metrology grade meter. Not all cal labs can do it.

@henningschaferhoff1533 10 жыл бұрын

Isabellenhütte is an old german company specialized in precision and load resistors. they were founded in 1482!

@KX36 10 жыл бұрын

Interesting. What did they do in the 350 odd years before the resistor was invented?

@UloPe 10 жыл бұрын

"Hütte" in this context means iron works and that's what they did before resistors were invented.

@sprybug 10 жыл бұрын

It uses a 6502 CPU? Awesome!

@sprybug 10 жыл бұрын

iEugene1994 Yep, that's why I think it's awesome. :D

@blackIce504 10 жыл бұрын

it is 8.5 digit you can see the extra digits @ 32.21 so i will gamble to say 6047 and 6048 may have the same parts and just different firmware....ohh.de/6048.htm i am sure someone has the firmware stashed away some where.

@LEDtest 10 жыл бұрын

Regarding the current shunt resistor: I've seen some like it, been thinking of using them. Couldn't find that particular part, but some info on the material: www.isabellenhuette.de/en/precision-alloys/precision-alloys/products/zeraninr-30/ And a link to a pdf from a "current" product, although it seems to have been discontinued recently: www.isabellenhuette.de/fileadmin/content/praezisions-leistungswiderstaende/AZ-H.PDF Or maybe this: www.isabellenhuette.de/fileadmin/content/praezisions-leistungswiderstaende/PBV-Z.PDF

@eudorian111 10 жыл бұрын

KOAX!

@KyleRepinski 6 жыл бұрын

KOAX!

@frankbuss 10 жыл бұрын

I know PREMA, I have this 6 1/2 digits model: www.amplifier.cd/Test_Equipment/other/Prema-5000.html inherited from my grandfather, who was a voltnut, too, even with a 6 1/2 digits DMM only :-)

@muh1h1 10 жыл бұрын

Isabellenhütte, seams to m german :) Isabelle is a name, and "Hütte" means "hut" or "shed" :)

@lutzhoffmann5467 10 жыл бұрын

Isabellenhütte is factory specialised for precison-resistors, power-resistors and especially for low-ohm-precision-resistors, located in a small town about 20km away from my hometown. You may find more informations on their (german) website: www.isabellenhuette.de/praezisions-und-leistungswiderstaende/

@chineseprogrammer 10 жыл бұрын

yeah that's the problem with ebay. I bought n analogue tektronix scope off ebay for 60 quid. The bastard didn't package it properly. It didn't work when it arrived. I bet the crt was totally smashed because I could hear what sounded like rattling glass when I took it out of the box. What is the neck of the tube made of GLASS!!

@nitinkumar29 7 жыл бұрын

I work in a German company and I have seen my colleague to do such ugly after thought modification.

@africanelectron751 10 жыл бұрын

I want one!!!!!! or two

@TheLucaE98 10 жыл бұрын

Isabellenhütte (it's like "iiesabellenhytte", type that into Google Translator German to English and listen to the english word) is a German Company wich is specialized of producing precision current shunt resistors. de.wikipedia.org/wiki/Isabellenh%C3%BCtte_Heusler

@Shawn_White 10 жыл бұрын

KOAX!!

@Fuzy2K 10 жыл бұрын

24:50 -- Bre-ke-ke-kex, Ko-ax, Ko-ax :P

@ObviousSchism 10 жыл бұрын

Winner winner chicken dinner!

@wgenerotzky 10 жыл бұрын

How does someone hand age something? Perhaps they pay people to worry the components about in their hands? Great job for the new generation already highly skilled in worrying about smart phones 24-7.