#1029

[@andyhowlett2231]

About 10 years ago I ordered some IRF740 powerfets from a low-cost mail order place. They arrived quickly and I built them into an RF power amplifier designed to deliver about 25 watts. I struggled for hours to make it work properly, fiddling with the driver and output transformers, thinking I must have got them wrong somehow. But it refused to deliver more than about 8 watts, beyond that moving into serious compression and the efficiency was poor. I changed the FETs (from the same batch) but nothing improved. In the end I decided it must be the FETs and I ordered some more 740's from a more reputable retailer. BINGO! 30 watts straight away and good linearity. Damn the Chinese.

[@RobCCTV]

In the 90s I used to have an electronic component business. I often used to encounter fake power FETs and memory chips from China.

[@jamesplotkin4674]

Might your company have been ORA, MCM or TEDCO? Bought loads of components until I couldn't ;-)

[@PapasDino]

A lot of times you can clean off the marking to find another underneath!

[@henrikstenlund5385]

Recently I designed a card for a foreign customer using the known LT1990 industrial opamp. That is an excellent special amp. The customer had purchased the necessary lot of 1000 chips (likely from China). The cards went to production and then to testing. None of them worked. I had to investigate them and realied that they could not work at all. The chips were internally shorted at supply pins. All chips had o be pulled out and replaed with an original chip, now working. The false chips had proper markings.

[@charlessmyth]

This is why I buy from legitimate suppliers, such as RS, Farnell and Mouser. Just bought a pair of AKG K240 MkII headphones directly from AKG (that has that option), to be sure they are what they claim to be :-)

[@netautorisationnetautorisa545]

*YES .... DO NOT "DESTROY THE OWN COUNTRY" ..... 100% **#NOT** ..*

[@peroleable]

Who do you think are producing what you buy on Farnell, RS and Mouser?

[@mbak7801]

@@peroleable Yes but they are checked and guaranteed by Farnell/Mouser and probably not manufactured in China. Buying from China is most likely fake, next QA rejects, next anything in an 8pin DIL package. Dismantle a known brand Chinese product and you will not find Chinese parts inside.

[@allansmith6140]

@@peroleable We are not discussing who is producing what, we are discussing the re-branding of components that have most likely come out of the dumpster of the companies you are referring to. This has been going on for years. There are reputable sellers in China who sell real parts, but they are as rare as hens teeth.

[@springrollwang4441]

@@peroleable as far as I can see, most audio electronics things on taobao are fake. caps, op amps, transistors. I think the component market is very twisted there, if you don't scam people, you can't really out compete with ocean of scammers. It's just a reflection of Chinese's mentality. and Chinese consumers are cheap as well which feeds the circle.

[@andyfraser5876]

I recently bought a bench power supply kit. It was a nice quality circuit-board, and the parts looked OK apart from the 3 op-amps which were supposed to be TL071's, but were unmarked. Once built, the kit was behaving strangely, so I suspected the op-amps; replacing them with genuine ones fixed the problem.

[@mbak7801]

I know the kit you are referring to. I did the same with the same result. Often the active devices are junk even if the PCB is good quality. Beware the caps as well. Larger caps have lower value ones installed in the case of the larger one. All that effort to rip off a few of the foreigners they hate so much.

[@gordonwelcher9598]

@@mbak7801 Why do they sell dangerous products to foreigners?

[@copernicofelinis]

Yeah, this happened to the ne5532 I bought from Amazon. According to datasheet the slew rate should be 9V/us. The fakes I received were 2.2V/us. Also, no sign of the input protection diodes. Being Amazon, I've been immediately refunded, but I guess the rule with 'third party vendors' is that chip markings are just decorations, and have nothing to do with what's inside the package.

[@IMSAIGuy]

you got me thinking. I looked at the NE5532 parts I had. All the JRC ones were good, all the NE parts were junk. as you say bad slew and no diodes. I have about 5 bins of various JRC opamps but fortunately only the 5532 bin had fakes in them.

[@drozcompany4132]

Out of curiosity how are you measuring the slew rate?

[@IMSAIGuy]

@@drozcompany4132 inverting amp config, gain -1, square wave input, measure rise time. about 0.5uS for 3.5V so 7V/uS. very crude measurement but useful to spot fakes. it is obvious, fakes were 10x slower

[@ranbymonkeys2384]

How did you measure that slew rate?

[@ranbymonkeys2384]

@@drozcompany4132 You aren't the only one.

[@gregvanpaassen]

The easiest thing to measure, quiescent supply current, is all by itself usually enough to tell you an op amp is fake. All the fakes in my op amp collection that I've identified so far using quiescent current could plausibly be LM358s, but they're probably out of spec in some other parameter.

[@W4BIN]

A LM358 can't be confused with a ul741 as the ul741is a single and the LM358 is a dual. Ron W4BIN

[@argcargv]

Just to be pedantic, but the circuit you have might be a bit off on the offset voltage if there is a small input bias current. A typical 100nanoamp input bias would account for a 100 microvolt drop across the 1k resistor. At any rate, your test definitely shows the op amps are fake.

[@SeanBZA]

Balancing resistors for offset input current, and if you want a bigger reading, you use a 1k resistor to ground, and for the inverting input a pair of 2k resistors to give a gain of 2, but with impedance in both legs being 1k. Gain of 10 would have made it worse as well, but easy enough to make the current flow through the same impedance both legs, meaning the bias current is compensated for.

[@vincentrobinette1507]

Typically, the DC bias is the same for both the positive and negative inputs. He used 1kOhm resistors for both the feedback and ground, to eliminate error caused by input bias. That way, he could measure from the output of the Op Amp to ground, negating the 10 megaohm loading of the meter, to give the accurate offset voltage. That same ~100 microvolts would appear the same for both inputs, canceling out.

[@frankkienast9106]

Could be worse. I bought some 2N3819 JFET transistors from a US seller on Amazon. Price was in the normal range. They would not work at all in my application. I then tested them with a transistor tester, where they tested as NPN. Parameters are suspiciously close to those of a 2N2222. Each package says 2N3819. Didn't bother sending them back, but I reviewed accordingly on Amazon. That's when I noticed lots of negative reviews for the seller saying other parts were not "as expected".

[@IMSAIGuy]

Amazon is a joke. I kept buying used Raspberry Pie computers that were just a scam and never shipped the product. Did this three times, each time Amazon refunded me. Then instead of admonishing the sellers. They told me not to buy that product.

[@stormz4040]

I had the same problem with JFET transistors on eBay. The package said J201 (this is a JFET model) but these components were actually BJT transistors!

[@sullivanzheng9586]

For anything that has a critical analog performance requirement (like RF transistor/JFET, low power/high bandwidth op-amp etc.) I only buy from legit vendors. It saves time. And for "digital" components like MCU, low speed logic gate etc., I may try ebay a bit since they are much easier to test/verify.

[@RyanBoggs]

Lol, that one low offset 741 behaves like it could be a repackaged OP07.

[@salec7592]

Are they at least very nearly tracking each other in regards to offset? That could mean they actually were trimmed, but someone screwed that up and devices were rejected in QC

[@IMSAIGuy]

no not even close

[@mnoxman]

The cost delta for a garage tinkerer has to be in the low 10s of dollars between Digikey and the Mao-dollar-rama. I am not sure why I might subject myself to "fake" parts unless the parts I was seeking are EOL or unobtainable through more standard routes. Buying from ebay is like going to the circus for a fine dining experience. Your going to be disappointed.

[@ranbymonkeys2384]

I tell people all of the time not to get op amps off of eBay.

[@winstonsmith478]

"From China" Same for any rubber ducky antenna claimed to be anything other than 2.4 GHz.

[@vidheadrum]

Even the IC sockets come pre-oxidized

[@hutasunet]

Nice video! In times like these it is important to check the parts :)

[@ferrumignis]

Most of the Chinese knock offs seem to be remarked LM324, looking for crossover distortion is a good clue. There is a thread on Eevblog with a bunch of die photos of various fake opamps.

[@marksandlin8376]

I ran into fake op-7s where I work. After look them over it could be seen that they had been top coated and relabeled. The leads had also been trimmed meaning they probably had been removed from a previous installation. These parts were bought like 20 years ago so this is a common problem. I keep bugging our people here to update to newer part numbers so we aren't having to buy old new stock.

[@MsFireboy2]

Thanks Alan. I’m finding out if you want quality parts I usually buy from Digi-Key. I trust them. I love your videos. I’m building a curve tracer. Took two of your circuits with slight modifications.

[@jwc4520]

Once upon a time 55 years or so ago. I was building the latest do gadget, which required a quad 741 op amp. After designing the circuit board, and for some reason installing sockets for the ICs I installed the op amp, bought from a local vendor. Next the smoke test, where I would power up the circuit for the first time. My goodness I have built a plasma rocket ... the circuit wasn't happy to just let the magic smoke out,.... the op amp, spit flames from the pins and flew off the board. Rebuilt the board replacing parts from a more expensive vendor, and it worked fine, so yes sometimes parts are not what they seem.

[@garydirkse9900]

This is common. I have fake batteries, timers, counters and Voltage regulators. Some don’t function at all. Some work at five percent of specifications.

[@y秋-c6f]

There are probably some rudimentary op amp chip masks from the 1970s in China (copycats such as LM308, LM324, LM082) because there are many products of the same model number that differ only in the prefix. I think there is a foundry that has been commercialized. I have been hurt many times. The first sample is good.

[@funkbungus137]

my very first time buying bad ICs was an 'on the whim' purchase of 10 pt2399 karoke echo chips from ali-express for something like 1.10usd total. I Threw them in a drawer to use whenever I got around to making a delay effect pedal for my guitar. when i finally used them, out of 10 chips, one could output audio of any sort, but the weird thing is the only bit that worked on it was the low pass filter pins, nothing else. I was .. well i wasnt shocked but I learned my lesson.

[@randydicotti3975]

I was hoping you would tell us the entire setup / schematic you used for testing them. Maybe next time.

[@Galova]

Oh thanks for info! Are there some other methods to test different op amps for fake?

[@IMSAIGuy]

kzbin.info/www/bejne/b3LaoYyef7unmsU

[@tigercat3864]

It's getting harder and harder to find legit parts. Even Digikey is cracking; they're now including "Marketplace Product" sellers (chinese junk) in their inventory. Will Mouser race Digikey to the bottom?

[@sullivanzheng9586]

Well it is driven by the market. Lots of people just can't resist the low price. For most hobbyists, if there is less than 30% chance of getting fake parts, they are willing to give it a shot, especially they can get reimbursement most of the time. And technically, these parts are not Chinese junk but US junk since there was a long supply chain of selling US electronic junks to China for "recycling" and there were scavenger groups ripping off the old parts from PCB, sorting and reselling them. In 2017, Chinese government has banned such electronic junk trade for environmental concerns and what you can buy from aliexpress now (especially old DIP packaged parts) are possibly junk inventories before 2017, which makes their quality even worse. SMT parts from Aliexpress are of (slightly) better quality because less % of them are from recycled junks. Some of these parts are substandard parts that failed performance test, but they are from original factories or dealers. So if you application is not mission critical, you can still try them. If time is valuable, use a professional channel like lcsc for Chinese parts.

[@Starbuckin]

@@sullivanzheng9586 I buy my chips from Unicorn Electronics Pennsylvania Never had a problem and way cheaper than Digikey Mouser or even All Electronics

[@sullivanzheng9586]

​@@Starbuckin Cool, thanks for the tip. The website looks minimalistic but their catalog seems a great fit for building up basic inventories and discontinued components for hobbyists/ repair work.

[@Illegal-Swede]

I once bought some fake OPA4134's in a DIP package off a Chinese vendor on ebay. (It's the quad version of the OPA134/2134.) They're a JFET input opamp that's great for upgrading a TL074 for noise and slew rate. At $4 each the price was amazing considering the DIP package version was out of production. When I got them they tested exactly like a TL074 which cost $0.15 or so in bulk (half the supply current and same noise as TL07 series). They looked EXACTLY like real Burr Brown chips. Super bummed....

[@PaulaBean]

This is sure a sign of the things to come.

[@winstonsmith478]

Are you sure the superstar Korean 741 isn't a dead IC? And take a Q-tip with acetone to the markings on the Chinese ICs.

[@IMSAIGuy]

these were laser engraved

[@Armadurapersonal]

What camera do you use? Looks excellent

[@IMSAIGuy]

Lumix GX7 with Lumix G X Vario 12-35mm f/2.8

[@underwoodblog]

what type of resistors are you using? these don't look like normal metal film ones.

[@IMSAIGuy]

beautiful soviet resistors.

[@stormz4040]

Unfortunately I already had some issues with some Chinese products, especially about JFET components.

[@BryanDenham]

what brand/type of resistors are you using? they look really nice id like to build with nice looking resistors like that.

[@IMSAIGuy]

from the Soviet era

[@BryanDenham]

@@IMSAIGuy figures they are no longer made LOL, when i saw them i thought to myself they would look so nice in a point to point guitar pedal . im just getting into making my own pedals and finding that a lot of the components i gravitate to for my pedal circuits are no longer made .

[@paulcohen1555]

I'm NOT surprised.

[@craxd1]

I used to buy LM741s by the tube, I think fifty at a time, for about 0.50 a piece, and I think they're about 0.85 now. These are TI parts at that from a major US distributor. Can you imagine what the Chinese manufactured ones sell for in China? Probably 0.10 or less a piece.

[@tiftik]

Here's another way to verify if a chip is good: break it apart using a vice and pliers. Take the piece containing the die and put it in a test tube with concentrated nitric acid. Heat it outside (since the fumes are bad for you). Rinse and repeat until the die is separated. Then look at it under a microscope. I find this process quite fun. It allows me to verify if a Chinese seller on Aliexpress/Taobao sells garbage or genuine stuff. If they are selling the good stuff, they get more of my money :) There are actually honest sellers who sell genuine, used chips without relabeling them.

[@IMSAIGuy]

I'm not comfortable with fuming nitric acid.

[@estebanvillalobos2303]

i spent about 40 bucks on fake op amps, i was pretty disappointed and disheartened

[@riccardoiii9882]

I tested the gbw of chinese opamps and It was not as datasheet at all. I cant Remember what It was

[@markopinteric]

I measured -3mV on my Chinese OP07s. How is that even possible?

[@IMSAIGuy]

Hint: It is not a OP07 kzbin.info/www/bejne/hITKooyCgbWIidUsi=AGltAdbb8I6Kc0rr

[@markopinteric]

@@IMSAIGuy Thank you for the answer. I suspect that in this case it's better to just throw away the entire OP07 batch, because you never know what's really in it. It would be interesting if you could make a video on how to test basic OPAMP characteristics, for example offset voltage, voltage swing for rail-to-rail opamps, other important characteristics... For example, I also bought the MCP6002 and connected VDD to the non-inverted input instead of ground, and the output voltage was really only a few millivolts below VDD. However, I don't know what else I should test to be sure that my MPC6002s are suitable for use.

[@IMSAIGuy]

I made this for testing an unknown device with a good device: kzbin.info/www/bejne/fKurYYl7l65qq7Msi=wMG0g7ACsKL_39-h

[@markopinteric]

@@IMSAIGuyI bought OP07 in a regular electronic shop in Europe and again it does not work. Are you testing it with dual supply or single supply?

[@IMSAIGuy]

@@markopinteric dual

[@mr1enrollment]

this kinda stuff just pisses me off. the lack of integrity for Chinese manufactures and vendors is legendary. and then our lack of pressure to control this behavior or block it at the border is absent. so we need to add more time and effort into acquiring and testing parts. who is it good for?

[@rjordans]

It's not just the Chinese, plenty of resellers around here that sell hobby parts with dubious sources. Many people may not care or realize that they get different parts but it's very annoying if you do need to get the right component

[@gowdsake7103]

Happens in all country's with many products

[@victortitov1740]

yeah, we got some fake ad797 from a reputable seller here in russia. They were fake to the point they didn't even work, i figured out the bad guys relabeled a dual opamp, but ad797 is a single one!

[@sw6188]

If people stopped buying their shit, they'd stop making it. Trouble is everyone wants something 'cheap' - so they make it and people buy it and the cycle persists.

[@rjordans]

@@sw6188 the resellers around here will happily ask the higher price around here for the same counterfeit chips. Avoiding the cheap version won't give you any guarantee. Either shop at known good suppliers that buy directly from the manufacturer or you take the risk. The problem is the effort in finding out if something works properly versus the cost of the item. Noone is willing to pay for test sampling components from each new batch you receive except for the military and aerospace. Even then, I've seen reels where the first 100 or so components were reel but those that came after weren't

[@mikebond6328]

Chinese parts are hit or miss. I think more often miss. Enjoyed the video. Thanks.

[@SeanBZA]

They can be really good, though then you have to realise that the price you pay is the same as what you pay for them from the top tier suppliers. Sort on price alone and you will very likely get either fake, reject or rebranded parts, though a pretty good amount of them will sort of function.

[@qzorn4440]

interesting, so far the cheap chips i get seem ok, however the pins bend easily and can sometimes break when pulling out of the socket like they are smt material? 🤔thanks ☕🥧💡

[@gavindingley2268]

Wondering if they're copies that have not been laser trimmed, rather than repackaged 741. What's the bandwidth, is it the same as a 741? I had some TL071 op-amps, which were fine, but had a lower slew-rate compared to the legitimate article.

[@copernicofelinis]

In my experience, cheap opamps sold on the interwebs are usually just four or five designs that get rebranded to whatever part number is trending at the moment. Someone on the eevblog forum decapped many opamps ics and found the same kind of generic opamp, no matter what the markings. It's some sort of slightly faster LM358 (in single, dual or quad configurations, to match the fake part number pinout) and that's it. Like all LM2596 on unofficial channels: they are some sort of low power 2576 clone. They can be useful if you know their limitations, but they certainly are not the real deal. Also, I suspect all transistor kits contain at most two or three types of actual dies, no matter what the markings is. They are probably binned by hfe and maximum voltage.

[@jjoeygold]

Can you xray or microscope the parts to check the die makings. Usually the part numbers are on the die

[@IMSAIGuy]

no, don't have xray, tried to crack open some parts but they don't cleave in the right way. don't have the chemical do dissolve.

[@jjoeygold]

@@IMSAIGuy see some KZbin channels where they dissolve in acid or slowly grind off the top. How about the markings on the top or bottom in comparison to an OPA. Some might be able to provide genuine OPA pictures to compare.

[@IMSAIGuy]

@@jjoeygold I will show a real OP-07 in a future video. The 'decap' process with acid is the correct way. I'm not going to do that. The offset pins either 741 style or OP07 style are missing on this device. There are 3 no connect pins.

[@cliveradvan3414]

I purchased a batch of 1% MF resistors and majority of the low vales ones (less than 100r) where close to 5% tolerance. I suspect seller purchased bulk stock at a discount because manufacturer had rejected them.

[@mbak7801]

Buying 5% resistors these days I often find they are very close to 1% anyway. I guess buying the 1% parts from a reputable vender just guarantees stability within 1% for a reasonable lifetime.

[@keithammleter3824]

Two other useful ways to tell suspect eBay op-amps apart - measure slew rate and noise with a CRO.

[@IMSAIGuy]

I will be doing slew rate in a future video

[@ferrumignis]

And look for crossover distortion, many knock offs are remarked LM321/LM324.

[@keithammleter3824]

@@ferrumignis : Good point - the LM324 has much higher cross-over distortion than almost any other op-amp. But cross-over distortion isn't a data sheet spec for most op-amps, so if you are claiming a refund on the basis of LM324-like levels, you might need to write your reason carefully.

[@packratswhatif.3990]

How sad as I have found the same in most items bought from China. It would seem that to the Chinese market, that money comes first THEN quality and honesty. No honor here …

[@sw6188]

That's exactly how it works. The chinese philosophy is all about "how much money can I make right now?" This is at the expense of reputation and quality. They don't care if there is no quality - they know you're not going to ask for a refund on a few dollars, and even if you do - they've just sold a thousand dollars worth to someone else so they don't care. It's like this - if someone in china is offered $100 today, or wait 2 weeks and get $400, they will take the $100.

[@stevejagger8602]

The only honour is amongst thieves.

[@maggotbrain7499]

@@sw6188 They know that people form the west will fall for the cheap trick, and keep coming, bc they are ripped off in the west.

[@camelid]

The only people mostly safe from getting ripped off by Chinese vendors are members of the CCP. If you're in China, you screw them at the risk of your continuing health.

[@gordonwelcher9598]

Surely they have "Lost Face" by not satisfying the customer.

[@-yeme-]

couple of years ago I bought 20 DIP LM358s from ebay and they were all completely dead, none of them did anything. it was as if the legs were just going into little slabs of plastic. I wish Id dremel'd into one to see if there was actually anything inside. and LM358s are super cheap anyway, you wouldnt think it even worth making fake ones.

[@IMSAIGuy]

most people think all the face chinese opamps are repackaged/relabled LM358s. They even fake those, amazing

[@axontech]

I test every electronic device/part I buy off of EBay - even if it is a USA seller - and I ask EBay for a refund if the parts don't work in my circuits / tests. EBay will get refunds, although I think they look the other way with large volume sellers from China. EBay makes too much money off of fees. I wish the FTC or an agency of our government would monitor foreign products more closely.

[@kevinscollan8293]

Its normally the bargain priced stuff that's fake I mean 20x for for under $2 is obvious, common sense bruv.😎💕🖖

[@keithammleter3824]

Yes, its not just in China that there are dodgy sellers. Rebranding fraud is not a new thing either. Rebranded semiconductors have been around since semiconductors were invented. Those of us who experimented in the 1960's remember things like Clive Sinclair in Britain selling rebadged reject Plessey 3 watt RMS audio amplifier IC's as 5 watt RMS IC's, which he called "IC-10" so that the gullible would think they were 10 watt amplifiers. A genuine 2N3055 (1970's era power transistor) is a rugged diffused type with quite a large chip, resulting in good linearity in amplifier service. Various minor US companies sold transistors labelled 2N3055 that were small chip planar types that were very non-linear, tended to oscillate, and tended to blow up. Lots of stereo amplifiers got blamed for distortion when in fact it was the fake power transistors. On the other hand, each time I have bought something from a Chinese eBay seller that arrived crook, when I reported it, the seller promptly sent replacement good parts, whereas certain USA firms will fight you over it.

[@kevinscollan8293]

@@keithammleter3824 yes I've never had any trouble with Chinese sellers and refunds,I buy a lot of bargain chips, 555s and lm op amps and never have any bother with them it's the more specialized or expensive ICs that get faked a lot,and transistors of course.😎💕🖖

[@gordonwelcher9598]

The worst thing is dangerous products.

[@keithammleter3824]

@@gordonwelcher9598 : Well, the worst country by far in that regard is not China, it's Britain. Some of their products over the years have been banned in my country (Australia) due to serious safety hazards. And they were not products from mail order or ebay from suppliers you've never heard off, they were products from major British brands sold through regular distribution channels. Example: For nearly 50 years double insulation has been standard in portable electric drills. A company I worked for bought a quantity of electric drills made by Wolfe in Britain. They turned out to be not double insulated, which is bad enough. But someone in Wolfe had connected the three wires in the power cord to the plug randomly. Each drill was different. There are 6 ways to connect 3 wires to three terminals. Two of them result in the motor being powered via the earth. One results in the drill chuck being live to 230 volts. Another makes the motor inoperative but the chuck is live. British disregard for safety isn't limited to electrical and electronic products. A friend of mine was very seriously injured in a moderate speed car collision because the seat belts in his British-built Land Rover failed. Any other vehicle, he would have walked away without even a scratch.

[@Pickle136]

take some acetone to label and usually with rebranded chips it will rub off.

[@IMSAIGuy]

laser marked

[@krusher7773]

What's an op amp??...lol. just recently caught the electronics bug...very interesting!

[@byronwatkins2565]

You should change that feedback resistor to 1M and add another 1k between inverting and ground so the amp will amplify the offset to mV for you. Except for shipping, 741s for that price is not too bad of a deal.

[@IMSAIGuy]

one company uses a gain of 4000, one company uses a fancy circuit with expensive parts to measure. the parts are not even 741 since there are no connections to the offset pins.

[@byronwatkins2565]

@@IMSAIGuy They also are not all alike; however, they do seem to be opamps and worth something. I would use them wherever they work.

[@michaelschwager786]

Now I know what input offset voltage is in the op amp datasheet. Thanks. :-)

[@IMSAIGuy]

I have a future video that will discuss it a bit more. about a week from now

[@warpigs330]

I am looking at JLCPCB's smt catalogue and they list SMT OP07 from TI for $0.39. That seems way too cheap to be true.

[@IMSAIGuy]

sounds fishy

[@warpigs330]

@@IMSAIGuy Nevermind, it was an OP07CDR, which are out of stock, but normally like $0.60 at digikey.

[@Ind421]

I tried monostable with many IC but none were getting triggered. I changed the design as all components were from China with no guarantee.

[@soccerstar99]

Fake crap from China nothing I haven't seen BUT where did you get the 2x1 through hole IOs??? I'll buy with referral link.

[@IMSAIGuy]

these? www.ebay.com/itm/303595310350?_trkparms=ispr%3D1&hash=item46afb0cd0e:g:jbgAAOSw5lxe5O1Y&amdata=enc%3AAQAGAAACoPYe5NmHp%252B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsSzaVbXtmGxqmWnpn8RLN2q8BAqx65x%252Bq1qC%252B6wx1jLa8bILDaXx2SvFD7BMGJyWHpxL33%252BOEEUEUb3iVzWLAfJIdAbImThcFwXlAwtJH0P%252BGfLaa4vhVSMEIl4MKjrDkg%252FwvX9G5VLvCyjIBC5oD51RNpuaPloTcK7ZFBP0jTTpr3dZDOx7M9WsoIQQ1WXSYc17pfGhVkAoXnyOuGx8MDz%252BlBQuH65QzcC%252BMvbJT92aIkkhAaCkx1h6S%252FLmOBWYvuZsLIVbYHLsMX%252BCU4GyVGJPyVNWg6qJ1zMIEM2%252FmF0qN17csyaF%252FD3dQ8oXpuF%252FMMIRQf7458cprIWxCsfImvN1jm5ulN4j55cNsjHZU3lsP1guBEwbhfEIGjo2xMEn2QsVGi3q%252B9X%252BI7iIhGrj5SXqF02u1x5DXQQcCFJxkKycWExO6ddGbibcwaZ2LqVkYi298XGeL6t2KeL1sZWrWW8Q9DHadBTTu0u6KfI248Zu%252FGNNgNgcJ9bO41wAATDRpG54BhSLsoK49EqF1vG9DwrQfRzXoK6imDtHJCNRb63DMbuygyrBGkKGR3iqeNrJfmjvjZ9jZ3bvBBh7MzuepwHaZclDKJmwj%252BL24dFjLDUIrkbVN5cD9bugpigmVFV8sX46lgEM0wuRG%252BLMVlkfR8GAFeNpC275hOwJ0AVLmazLkcHIqqqCjhWL1%252FKCdcMv25shtEMfZN5CFAxxHl75ZkBKJ8z%252F8ihwUZj96ViAbc5uTd1muU4Yvf6nmqQJ5d8fVNhSpYKoudWnIw7CdGdavMG3CPRDxmXqag2f6ub62J%252FS0J4kgy%252BVk5g51IpNFueQysAWPeRVzpTqv%252Fnwiuh0J4wQ%253D%253D%7Cclp%3A2334524%7Ctkp%3ABFBM9Jb95tVf

[@soccerstar99]

@@IMSAIGuy YES I didn't know how to search for it. Was missing "breakaway".

[@earthlightsmusic2743]

I've been getting components from the proper suppliers for years. Assorted untested (such as from Poly-Paks of So Lynnfield, MA, and th elike) are for those willing to their own screening, and full price for those who want 'em screened. But now E-Bay and the like are selling such devices?

[@IMSAIGuy]

polypaks wow that's dating us

[@Broken_Yugo]

These aren't polypak type floor sweeping/overrun stuff, they're outright fraudulent, some cheaper opamp marked as whatever sells, if they work at all. Happens with all manner of ICs.

[@ivolol]

Ebay will sell whatever in the world a third party seller wants to sell, as long as it's not outright illegal.

[@igorev6391]

It would be nice if you gave a link to the seller. In addition, many are wondering if it is possible to buy high-quality operational amplifiers from the Chinese. There are practically no videos on KZbin about buying quality parts from the Chinese. Thank you for the video.

[@hinzster]

The link to the seller would probably be worth as much as these "OP07"s. Those sellers most of the time pop up and disappear faster than their wares. That said, there *are* some good sellers in China. Looking at how long the store has existed (on AliExpress or whatever) gives a hint, although it's not a 100% way to be sure. The seller marking their stuff as "used" or "new old stock" could be another hint. And besides, $1.88 could be a somewhat ok deal for 20 new 741s as well, depending on how much you have to pay for shipping. Except that wasn't what you were looking for :)

[@igorev6391]

@@hinzster Thanks! And I once bought 10 pieces of genuine LM833 for a dollar.

[@jfmax2000]

Great Community Service Video Here.. Thank You for The Heads Up 😎💯💯

[@Kreln1221]

*I've heard of fake JRC4558 Op-amps as well, made famous in the TS-9 Tubescreamer, and a bazillion of its derivatives...*

[@arinascimento547]

It happened to me buying THS3091 on eBay. They showed at least 1/20th of the expected bw. I got a refund as well.

[@frankcomputer1859]

Hey! You use Sakura pigment liners! My favorite pen!

[@NightRunner417]

Mmmphhh this is actually strongly on my mind lately. I'm wanting some OPA637 chips and they're *not cheap*. Very good amps, like really good, but you for sure pay for what you get. So off to eBay I go and I find them for half the price easily. I haven't been able to make myself do it, I just don't trust em. So am I really gonna blow like $120 for three chips on Digi-Key?

[@IMSAIGuy]

Arrow has them for $30

[@IMSAIGuy]

Hilariously, China has them for $5.50

[@NightRunner417]

@@IMSAIGuy ROFL yeah I'm sure it's especially hilarious when your swanky 80Mhz capable Chinesy chip knockoff somehow can't squeak above 1MHz on a good day, lol. Arrow though I will check out, thank you. :-)

[@niklogin96]

Все операционники что продаются на Али делаются из LM358.

[@IMSAIGuy]

I believe it

[@ALEFILES]

If you like to be scammed, buy Chinese...

[@carloca71]

I guess I was lucky with the OP-07 I bought, not tested yet but they look original, no painting, no matching serial numbers, a bit dirty and with socket marks on the pins, the ugly ones looks to be the best ones... Not so lucky with other sellers, the new painting over the component make it impossible to find out what was the original marking and a giveaway: matching serial numbers or whatever on the top but the short codes in the bottom all different. That ones from the factory molding.

[@om_WHAT]

하하하하하~정말 어메이징하다..op-07인데? offset이 수 mV라니?? 이거 정말 실화입니까?ㅎㅎㅎ

[@clam4597]

At such low price hardly a rip off. I paid $600 to have my roof fixed and got nothing properly done out of it.

[@IMSAIGuy]

having your roof ripped off does sound much more serious. There are unscrupulous people everywhere.

[@jdd1777]

In this day and age you can't lose, either get what you want or make a video about it and win at KZbin!

[@hgm6421]

Made similar experience with some AD8638. A 16V Precision OpAmp. The chinese version gave up at 15V. No magic smoke, but dead.

[@waltergeeraert3667]

I too have received many fake opamps through Aliexpress. Out of annoyance I was forced to design a few test PCB's with many jumper settings for multiple test configurations. And later for multiple opamp footprints. Occasionally received money back, but sometimes a dumbass on the other end who simply claimed: "show with photo that you received something DIFFERENT." No, the imprint is OK, but the contents of the chip are NOT! It does NOT conform to the datasheet. I made a story of it on a handmade website with a lot of test info. On the first line an option to activate Google translate. A link won't work, so Google "opamp test PE1ABR"

[@lordseph]

Opa2134, TL072, TL071, NE5532, 4580's 4558's, all freaking fake from China. As a new guitar pedal builder, these gave me quite a headache but I learned my lesson real quick. Now I only buy from trusted shops like Digikey, Mouser, and Tayda for my Opamp needs

[@peterknudsentupni]

I got tip3055 that expolded af 2A.

[@IMSAIGuy]

yikes. with a heatsink they are good to 15A right?

[@gkdresden]

In Germany we have the right to send the parts back within a month and get the money back. 😂

[@slordmo2263]

Hmm....the thing that pisses me off, is that there is no 'certification' for this crap.... I've heard of some of those chinesium 40Amp SSR modules that have started fires.... turns out, internally it was a totally under-rated switching device.... buy American if you can....

[@sw6188]

That's what they do - they copy the genuine device but make the die 1/10 the size so it won't handle the rated current, and when it tries to you have Cherbnobyl!

[@jensknudsen4222]

Been there, done that. I only buy nuts and bolts from China now.

[@repairman2be250]

Not so long ago I also ordered M6 bolts and inserts for a wood project - they were all good. Electronic components you better stay away. No 2N3055 or LM78xx series, you just get rubbish and have to apply for full refund.

[@pyrokinetikrlz]

well, at least you bought those for cheap. imagine paying 6 USD for each and then finding out they are actually LM741

[@karlfell3768]

I have just had to take a gamble on some 2n5160 to repair my old HP 8112a pulse generator. Not exactly cheap for China but was the only source I could find.

[@martinda7446]

Pretty good price for 20 741s ha ha.

[@bobaloo2012]

Gosh, Chinese seller on Ebay ripping people off, who'd have thought it? If it sounds too good to be true, it is.

[@ranbymonkeys2384]

Sum Ting Wong said they were fine!!!!!!!!

[@kurtfrancis4621]

@@ranbymonkeys2384 Sum Ting Wong is always looking for his next victim by the name of Wun Dum Fu

[@rjordans]

That first 741 clearly is a fake indeed!

[@SeanBZA]

No, I have had plenty that came in well within spec, really just luck of the draw as to where the part is when manufactured, though the manufacturers do tend to do an on die test to weed out the bad ones, and then a second pass after packaging to get the closest devices to sell at a premium. Just like transistors, where you can get a BC107, or a gain binned part that is BC107A, BC107B or BC107C, your choice as to price point, and if your application is that critical gain wise. Buy the plain part and sort if you need matched pairs, you will find 2 within 1% of each other if you buy 15 parts, and with the gain grouped parts you can even get a rough notion as to the actual gain.

[@alexstone691]

Wait i bought op07s from a distributor here and they are about $0.6 each

[@IMSAIGuy]

which one, I want to get cheap parts too

[@frankowalker4662]

The Korean chip might be military grade. LOL.

[@W4BIN]

Using only one tiny specification is rather a rush to judgement. How about the power consumption and noise level? The OP07 IC has two "offset" pins, so they can be used if all other specifications are met, it that is necessary. They are still audio amplifiers. I bought 250. 2N2222A's for $1.95, they are fakes, but the gain of every one that I have tested so far is ~700. instead of ~100. They are wonderful transistors. I don't see the problem if you are careful. Ron W4BIN

[@IMSAIGuy]

the offset pins on the fakes were no connects, not bonded. they probably used a part that did not have the offset available or used -V and the op07 uses +V

[@IMSAIGuy]

Just to clarify, these op amps are not audio amps. they are way too slow. the only reason to specify an op-07 is exactly for the low offset. If you are running an op amp at high gain, say x1000. then a 2mV offset would be 2V on the output. OP-07 are used in critical measurement applications. glad you like your transistors, I do not like my op amps

[@zukjeff]

Send one of the fakes to electronupdate to disassemble and photograph for us.

[@nofunnogain5297]

It is greed that makes people believe they can spend $2 to get $100 worth of product.

[@IMSAIGuy]

so China gets a pass? I've seen China vendors charging full price also, are those real?

[@nofunnogain5297]

@@IMSAIGuy I think when you believes Chinese can give you $100 worth product for your $2 payment, that is the problem. Maybe Chinese trained you think that way, but maybe it is you never want to pay fair price for quality products.

[@IMSAIGuy]

@@nofunnogain5297 no I've seen Chinese vendors with reasonable pricing give you fake products.

[@IMSAIGuy]

I've also see domestic vendors with old new stock sell parts at very low cost.

[@nofunnogain5297]

@@IMSAIGuy I do agree there are criminals in China.

[@decem_unosquattro9538]

1.80 for 20 pieces. A cup of coffee cost $4 here and you gotta drive there. I bought some timer ICs from China for $2 not even expecting them to turn up. They tuned up. I could believe it. How do they do it for that price? Here the bank charges me $2.50 to take my money out or they used to. Im sure you can use them even if they're rebadged. Only thing that made me wild is getting damaged goods or missing parts. Still the price is unbelievable. Buy more quantity. Just realise freight is expensive now. It will take some time before its cheaper.

[@v-mosfet4362]

Why buy on ebay? Chips from Chinese semiconductor companies have many better parameters than op07, based on cmos process, the power supply current is only a few hundred uA, they are cheaper

[@IMSAIGuy]

please give me a part number and datasheet for a chinese opamp that has 30uV input offset voltage spec and costs $0.10

[@tiftik]

@@IMSAIGuy Check out LCSC. Cosine from China makes wafer trimmed op-amps such as COS77 with 15uV offset and costs 12 cents at 1k units.

[@realcygnus]

We asked for it, we got it, TOYOTA !

[@ChadLuciano]

Toyota is a Japanese brand.

[@realcygnus]

@@ChadLuciano I know, somewhat ironically now that really entails quality as opposed to the time of the commercials & how the slogan was used.

[@ChadLuciano]

@@realcygnus I hear you, Japanese are more forth coming than their neighbors to the west are...Japan is an example of what China could become.

[@realcygnus]

@@ChadLuciano Yup. Though even more so I meant how we(the US/"west") not only allowed it(China becoming a super power by selling cheap slave labor 💩) to happen in the 1st place but, literally nurtured & guaranteed it, by moving virtually ALL manufacturing to them. & thinking we need dollar stores on every damn comer full of useless plastic disposable stuff. Not that it really says anything about their abilities or anything. They do some cool stuff too, hell they landed a craft on mars 1st attempt. But the fact that they're often associated with low quality is probably more the fault of the rest of the world. It almost takes the meaning out of, you get what you pay for. 🤣

[@technishn]

I bought 3 or 4 lots of ICs on line and about 1 in 5 were genuine. I worked out that the markings were different as were pin resistances, before I checked them.. Some were MC1350 from memory.. Yes...Buyer beware...

[@stevejagger8602]

Most everything from China is of dubious quality, because it is not possible for Trading Standards in any country to surveil the quality of everything entering their country. Standards of manufacture only tend to come to light long after the event when the system has failed.

[@EngineeringVignettes]

Guess I am an "old fogy" but I have just stuck with buying IC from the likes of Digikey, Mouser etc. Never been burned. It's _Caveat Emptor_ with chinese parts. Cheers,

[@1pcfred]

Dave Jones put up a video where he got parts from one of the major retailers and they were fake. So just because it hasn't happened to you yet doesn't mean it can't happen. That counterfeit stuff is everywhere.

[@pibbles-a-plenty1105]

If you don't buy your parts through factory authorized distribution you can be sure you'll be screwed. Don't blame anybody but yourself for being a cheapo.

[@IMSAIGuy]

☹

[@Ormaaj]

OP07 is an old part and nothing special to write home about. $6 is ridiculous. You should never pay that for an OP07. E.g. you can get the ADA4077 in low quantities for less than that - a drop in replacement that's superior in all respects and also available in duals and quads. There are numerous other upgraded replacements available from others that also cost less.

[@IMSAIGuy]

you can tell I'm old school. AD says this is a 6th generation for the 07. not a drop in: no offset adjustment, lower supply voltage range, SMD only. I do like it though, especially the dual.

[@Ormaaj]

@@IMSAIGuy True I didn't notice the missing offset trim and bit narrower range on the high end. +/- 15 is still quite versatile and you can usually live without offset trim. And SMD only. I like me a big old DIP from time to time. 😁

[@victortitov1740]

the good part about op07 is they are jellybean, available from multiple manufacturers. I love ad8676 for example, but can't buy them for a reasonable price anymore, presumably due to chip shortage.

[@antoniomonteiro1203]

This is not the proper way to measure the offset voltage of an opamp. It doesn't take into account the input currents that may not be equal. I believe you can find in the datasheet of low offset voltage opamps schematics to more accurately measure offset voltages. Note: this doesn't mean your conclusions are wrong. But I don't have confidence in measurements that are not very carefully prepared.

[@IMSAIGuy]

I should not have put in the 1k to ground, but that would just improve the number not make it worse.

[@saturn5tony]

China + cheap = can be very expensive 😅

[@nagasainathkoduru9995]

I had one I bought LM723 just like this

[@ranbymonkeys2384]

He who stand on toilet, high on pot!!!!!

[@michschep7601]

I dont buy new chips anymore...... i rip what i need out of scrap equipment....

[@IMSAIGuy]

wow, you must have a nice pile of stuff, what equipment uses the OP-07?

[@diorthotistm1621]

At least they are actually opamps that work, I think you should reconsider your accusations. You see, cheap parts from China come because they're out of spec, not necessarily because they are fake. For example, if you buy cheap 18650 batteries from China, you will get either fake batteries with 300 milliamp hours, or you will get out of spec batteries with slightly less capacity. Out of spec parts is what you would expect, if you are buying from eBay cheap parts from China.

[@IMSAIGuy]

I actually looked at the die from a real op07 and the fake one. they are different. The fake one also did not even wire bond out the offset adjustment. they are no connects. they are 1000% fake.

[@ronaldhofman1726]

i had once received fake xr2206 chips from china.