Counterfeit electronic components  - Page 1
Forum section: electronics / projects

author: atgeek
author_rank: Contributor
timestamp: November 13, 2016, 02:03:57 pm
content: Very often I buy electronic components on aliexpress, but I've heard that many of them are recycled or fake. Do you buy components from China or prefer to avoid them?

author: AndersJ
author_rank: Frequent Contributor
timestamp: November 13, 2016, 02:15:01 pm
content: I try to avoid everything chinese.I've had my share of product fails caused by fake components.Octal low side drivers and FET's for instance.

author: wraper
author_rank: Unknown
timestamp: November 13, 2016, 02:16:38 pm
content: Depends, generally you should avoid them if you care a little bit about them being genuine. Especially avoid buying transistors, opamps, voltage regulators, branded electrolytic capacitors as there is pretty slim chance receiving genuine parts.

author: CraigHB
author_rank: Regular Contributor
timestamp: November 13, 2016, 02:19:08 pm
content: I buy most of my stuff from the usual vendors like Mouser and Digikey. I have heard of people getting counterfeit components buying direct from China. You wouldn't think someone would go to the trouble for the relatively small amount of money involved, but it seems they will counterfeit anything. There's some savings to be had buying stuff direct from China, but the risk is there. For small quantities I wouldn't be too concerned, but if I was producing something and buying reels I'd be more careful.I think you also need to differentiate the level of counterfeiting. Some will go to the point of putting slugs in copied packages. Others will just copy parts where those copies still function adequately. So you're probably more likely to get non-genuine parts than non-functioning slugs.

author: joseph nicholas
author_rank: Frequent Contributor
timestamp: November 13, 2016, 02:44:29 pm
content: Almost all the transistors, mosfets, capacitors and resistors work from china. My experience with large value capacitors is mixed. I bought a few 63v 1,000uf capacitors which were marked new from aliexpress and the were taken from other circuits used. That being said, they worked fine.

author: JanJansen
author_rank: Frequent Contributor
timestamp: November 13, 2016, 03:04:56 pm
content: I use ebay for :LCD displays ( very cheap )heatsinksbreadboard cablesrotary encodes ( cheap, only i dont know how long they will last, i will replace them one day if gone bad )i also buy 10uF ceramic capacitors ( very cheap ), only others tell me not to buy that, i see no problem yet!For the rest someone told you can also buy pin headers from china.Active components not recommended, they fake labels.I also bought "germanium" diodes, they are fake, its skotsky diodes not germanium.They sell whatever the market wants.

author: wraper
author_rank: Unknown
timestamp: November 13, 2016, 03:30:38 pm
content: Quote from: CraigHB on November 13, 2016, 02:19:08 pmAnd this is the worst in it. You will get transistors with 5x smaller die, opamps with much worse specs. And this will bite you after some time, when your devices will start to fail at field. Would be much better if they were not functioning right away.

author: wraper
author_rank: Unknown
timestamp: November 13, 2016, 03:35:21 pm
content: Quote from: joseph nicholas on November 13, 2016, 02:44:29 pm"Work", before they fail. Especially higher power devices when decently loaded.

author: atgeek
author_rank: Contributor
timestamp: November 13, 2016, 04:55:27 pm
content: The problem is spot the original components. Many store out the China sell fake products as genuine.Would be also interesting create a thread listing counterfeit/used components and the store selling them

author: BravoV
author_rank: Super Contributor
timestamp: November 13, 2016, 05:33:00 pm
content: Why ? You want 100% genuine stuff and really cheap (cheaper than the mfgr's price like the common per 1K price) ?Live with it.Quote from: atgeek on November 13, 2016, 04:55:27 pmNowdays, using your eyes, finger, nose as for sniffingwont work anymore as they've perfected the cloning.Quote from: atgeek on November 13, 2016, 04:55:27 pmThen do NOT buy from there, go to Digikey, Mouser etc.Quote from: atgeek on November 13, 2016, 04:55:27 pmAgain, why ? They can make "another" new store again even they're blacklisted for thousands of times.

author: Tomorokoshi
author_rank: Super Contributor
timestamp: November 13, 2016, 06:24:57 pm
content: I like to post this link whenever a counterfeit thread shows up. It's a few years old now, and things have gotten only more sophisticated:http://www.asq.org/asd/2009/03/compliance/counterfeit-parts.pdf

author: JoeN
author_rank: Frequent Contributor
timestamp: November 13, 2016, 08:16:29 pm
content: Quote from: blueskull on November 13, 2016, 05:30:54 pmEspecially if you buy it from Digikey since at the s"genuine price" level, Digikey will be competitive. And for me, the postage on 8 oz or less of parts is like $3.50 and comes in 3 days.I'm not bothered by the counterfeit parts controversy as far as hobbyists go. Hobbyists get what they pay for and are mainly making projects to see if they work and then they end up in a box somewhere. What bothers me is that sometimes OEMs get screwed here, and frankly I can't see how it happens. Why are they buying from some dodgy middleman and then putting those parts into devices that cost 1000x as much as the part that is going to fail at a high rate and screw up their product for many users and kill the OEM's reputation? It's not worth it. And to avoid it, all they have to do is buy directly from manufacturers or from well known distributors (Digikey, Mouser, Arrow, etc.) that have a policy of only buying from manufacturers and never middlemen or liquidators.

author: amitchell
author_rank: Regular Contributor
timestamp: November 13, 2016, 09:58:35 pm
content: Quote from: Tomorokoshi on November 13, 2016, 06:24:57 pmI like the pile 0402 caps, hard to believe you can make money doing that with 0402.

author: Tomorokoshi
author_rank: Super Contributor
timestamp: November 13, 2016, 10:13:40 pm
content: Quote from: blueskull on November 13, 2016, 10:02:17 pmSpecifically what is biased about it?Yet, there they are, sorted and ready for packaging.Look at page 51 of 76. Reels of 0603 and 0402 are there for sale.

author: Tomorokoshi
author_rank: Super Contributor
timestamp: November 13, 2016, 11:27:16 pm
content: Quote from: blueskull on November 13, 2016, 10:28:27 pmQuoteThe presentation shows different aspects of the counterfeiting process. The parts being cleaned on the sidewalk were there. There were definitely analyzed parts that were counterfeit. Numerous instances of counterfeit parts have been documented on this site. It's relatively easy to purchase counterfeit parts and analyze them.QuoteWhat is the basis of the claim that in no way would passives not be resold?QuoteThe plastic reels may be new, but that's all that is new in them.

author: Stephen37
author_rank: Contributor
timestamp: November 14, 2016, 02:13:06 am
content: My rules are the following :There are Chinese copies of original chips that work even better than the original, for instance, the XL6009 regulator, the SS3x Schottky diodes or the CP210x/CH340 FTDI clones. But if you buy NE5532 opamps or LM7805 regulators you better test them before using in production because they might be from a failed batch, but you can get genuine parts from some sellers on ebay. They would still work but not in the spec of the datasheet. (which sometimes is a problem and sometimes not)

author: CJay
author_rank: Super Contributor
timestamp: November 14, 2016, 12:38:07 pm
content: I've had very few instances where components have turned out to be fake though admittedly I only buy as a hobbyist who repairs things for friends, if I were buying for manufacture (again) I'd definitely be taking time to check my supply chain more stringently and approaching verified distributors as a first source.I've bought many modules and bare components via eBay and Ali which have been and are working, to the best of ability to measure, at least to spec, without making any particular effort to choose vendor other than checking their feedback.The only parts I've spent time selecting and vetting suppliers for are RF transistors so I've been lucky in all but two instances where my chosen suppliers haven't been able to help, a 'Mitsubishi' RD16HHF1 device turned out to be a bipolar device that'd been remarked and a bag of 2SC2078s were bipolar transistors of some description but most definitely not RF amplifier transistors.I think there's a lot of FUD propagated about Chinese suppliers, mostly by those who have a vested interest in muddying their names.

author: wraper
author_rank: Unknown
timestamp: November 14, 2016, 12:41:19 pm
content: Quote from: Stephen37 on November 14, 2016, 02:13:06 amThey are not clones and have their own drivers.

author: wraper
author_rank: Unknown
timestamp: November 14, 2016, 12:45:34 pm
content: Quote from: Stephen37 on November 14, 2016, 02:13:06 amWhich is widely spread bullshit. You have very slim chance getting rejected components, just imagine how many rejects should be produced to fill that market. Usually you get either counterfeits or used components sold as new.

author: Siwastaja
author_rank: Super Contributor
timestamp: November 14, 2016, 02:23:36 pm
content: This is a constant subject of speculation andon the internet forums, which is funny, because there is a lot of community experience on the matter, if people just were listening.Anyone who hasactuallybuilt things using China Ebay components for some time will know very well that they are totally unusable, end of discussion. Still, people don't want to believe this and want to act like some Counterfeit Component Justice Warriors.So, it seems to take some time to find this through trial and error. I happily used Ebay parts for some time, and have seen others do it, until they realize.Reasons why this is not obvious right away include:1) Not all parts are counterfeit/broken - some parts are genuine and OK! I think it's generally around 50% (but depends hugely on the category, ranging between 0% and 100%). If you happen to be lucky for the first few times in the row, it may take a year or two until you notice if you are not that avid.2) Not all parts aretotallybroken - they appear to work first. Very typical examples: power components with wrong printings, it is the right type of component, but cannot do the current it's specified to (usually not even nearly so). Or, the necessary protections are totally lacking, which won't be seen right away.3) Some parts have much worse specs, but happen - by sheer luck - to be usable in that particular application.4) Some of the parts end up in the parts bin, not being used at all for some time, or ever, due to the nature of the hobby. People are left satisfied by the "good service".All of this delays the realization that the Chinese Ebay parts are 100% unusable crap, because even if 50% of the stuff is OK, you never know. Even for a hobbyist doing one-offs, this percentage of failure is at least an order of magnitude, if not two, too high.For me, it took some 2 years, with hundreds of dollars worth of components. And BTW, the Ebay list prices are usually not better than at real distributors. Free or cheap shipping was the enabler for me, when you just need $5 worth of components at the time.The need to buy everything twice or three times, writing complaints to Ebay and waiting for the new parts for 2-3 weeks at every step starts delaying projects so much that at some point, you realize it's easier to use that same 2-3 weeks to design and think what you are going to need in a next few projects, or gather some more people, and then order the miminum order from a real distributor.Nowadays, I only order the China Ebay components when the normal distributors fail to sell the product at a sane price, and the product is such that I know from experience it is most likely going to be OK - a typical example would be a pin header.

author: madires
author_rank: Super Contributor
timestamp: November 14, 2016, 03:03:57 pm
content: For my hobbyist needs I buy things like LCD modules, pin headers and LEDs from China. So far I haven't had any issues as I don't expect too much, only that it works and the LCD controllers to be compatible. For cheap LED modules I assume 1/2 or 1/3 of the stated power rating, until I've checked them myself. This "1 Chinese Watt = 1/2 Watt" rule works quite well for most cheap stuff.

author: CraigHB
author_rank: Regular Contributor
timestamp: November 14, 2016, 05:08:36 pm
content: I think it's all pretty amazing it comes to this. China is like the wild west of industry. You can get good stuff probably more often than not, but there's always the unscrupulous sellers you have to watch out for. The spectrum ranges from used genuine parts packaged as new, copied stuff with lower quality, or flat out fakes with no working circuits inside. Unfortunately there's really no way to evaluate the level of trust you can place in a China seller. There's so many of them on places like Ali and eBay there's just no way to know who's solid and who's sketchy.Big companies do get burned by this and I've heard stories of whole production runs that have been scrapped due to bogus parts. I think it's a legitimate problem in electronics and a lot of it stems from the bean counters trying to skimp on overhead any way they can. For the hobbyist it's only an annoyance, but it can be a disaster for large production runs.There is one thing that really dissuades me from buying parts on Ali and eBay even though there's no real loss of money involved. For bigger projects I have had issues that take quite some time to troubleshoot. To introduce those issues only because I wanted to save a dollar or two on parts in low quantity doesn't seem worth it to me.

author: CJay
author_rank: Super Contributor
timestamp: November 14, 2016, 06:09:21 pm
content: Quote from: CraigHB on November 14, 2016, 05:08:36 pmI think as a manufacturer you'd have to be desperate (or a moron) to buy parts from China on eBay, it's a hobbyist marketplace, at best for a manufacturer it's possible to buy things without having to buy a reel but even then I'd much rather go to the manufacturer and beg for samples or buy an eval board.As a hobbyist, I love ebay, it gives me access to all sorts of oddball stuff, things I can't lay my hands on any other way or without paying for thousands of and I tend to take my lead from other hobbyists who have already tested the parts and provided reviews/links. It's hardly the end of the world if a $1.50 board fails, it's a little frustrating but that's about it.For repair parts like RF transistors, as I've said, I have a couple of Ali sellers I trust and have never been let down by but I'm not ordering a particularly wide range of esoteric parts.Ali can be good for manufacture as there are verifiable parts available direct from the manufacturers in China, it's a handy place to find small manufactuers of things like switches, LED modules, small TFTs and in my non hobbyist role I have ordered LED displays direct from one such supplier, as far as I know they're still performing sterling duty to this day.It really depends what you are looking for and how much time you have on your hands.

author: CraigHB
author_rank: Regular Contributor
timestamp: November 14, 2016, 08:42:30 pm
content: Quote from: CJay on November 14, 2016, 06:09:21 pmOEMs don't always buy direct from the manufacturer. Some of the name manufacturers like Microchip and Texas Instruments have a wholesale outlet, but more often they don't. OEMs typically source from a distributor. They're not immune to getting a hold of bad parts either. Not sure how it happens, maybe those distributors are sourcing parts form the gray market where counterfeits make their way into stocks.

author: Stephen37
author_rank: Contributor
timestamp: November 15, 2016, 07:00:26 pm
content: It's definitely not worth it for a company to buy directly from China, you can go to resellers that have partnerships with Farnell,TME... and will provide you with a price 60-70% (even 90%) lower than specified on the non-partner website.

author: Siwastaja
author_rank: Super Contributor
timestamp: November 15, 2016, 07:02:40 pm
content: Wait, what? Manufacturers don't buy parts off Ebay? Breaking news! What else? Pigs don't fly?

author: RobertBG
author_rank: Regular Contributor
timestamp: November 15, 2016, 07:53:58 pm
content: Fake counterfeit parts are probably a big reason for hobby projects failing to make it off of a breadboard more than anyone cares to admitThey can make troubleshooting a absolute nightmare for the hobbyist.As far as the reputable wholesalers go,I cant say who it was but I was on the receiving end of one of them getting a batch of fakes.Now it was a mess but they eventually did the best they could to resolve the issue although it was on the verge of getting truly ugly.They eventually were willing to notify our customers that they were responsible for the product recall.Although I'm still angry that it took multiple lawyers to get to a resolution and part of me still thinks that they just got caught red handed.But if I say much more,chances are I'll be receiving a nasty letter from a attorney,especially if I say it on here

author: ZeTeX
author_rank: Frequent Contributor
timestamp: November 15, 2016, 08:39:14 pm
content: For me buying stuff from digikey, farnell, mouser and such is not a option most of the time.shipping can get extremely expensive, 50$+ expensive.fortunately a local distributor ships for 10$, But for a 1$ part 10$ is expensive, And I can't always order all the parts that I need for future projects in the same order.

author: CraigHB
author_rank: Regular Contributor
timestamp: November 16, 2016, 04:40:45 pm
content: Yes shipping can get crazy expensive overseas. You see a lot of these China vendors offering free shipping now. They'll offer free shipping on items that are only a few dollars. Don't know how they do it. Is there some kind of gray market for overseas shipping?

author: Wirehead
author_rank: Regular Contributor
timestamp: November 16, 2016, 05:37:36 pm
content: Quote from: CraigHB on November 16, 2016, 04:40:45 pmInternational shipping is sponsored by the Chinese government.Also, international postal laws dictate that when a foreign package arrives in a country, that country has to deliver it without cost.So there's your free shipping. China pays to get it to your country, the local offices take care of delivering it to your door.

author: JanJansen
author_rank: Frequent Contributor
timestamp: November 17, 2016, 04:04:54 pm
content: It amazes me that you can buy a complete hammer set for 1 dollar delivered world wide free shipping.

author: CraigHB
author_rank: Regular Contributor
timestamp: November 17, 2016, 05:48:31 pm
content: Quote from: Wirehead on November 16, 2016, 05:37:36 pmWow the Chinese government is not messing around in taking command of the global consumer market, good for them, good for us.

author: Bicurico
author_rank: Super Contributor
timestamp: November 17, 2016, 10:17:47 pm
content: My last purchase through AliExpress was to purchase 5 replacement IC's for the "138M-4.4G USB SMA signal source/signal generator/simple spectrum analyzer". I fried the IAM-81008 (labeld on the PCB as M810), which originally is a Agilent/Hewlett-Packard component with the title "Silicon Bipolar MMIC 5? GHz Active Double Balanced Mixer/IF? Amp".I got them really cheap, I don't recall the price but for sure it cost me less than 10 Euro.And after replacing the fried one, my device was up an running again.Did I get fake ones? I have no idea! But one thing I am certain of: they do work.The price? IC's with shipping cost less than shipping alone at Farnell & Co.My conclusion: if you are an amateur/hobby guy then try your luck at AliExpress. Worst thing than can happen is the components don't work. No big loss.If you are a professional, you should avoid fakes and gray areas (import from China) and stick with official channels.All said!Regards,Vitor

author: wraper
author_rank: Unknown
timestamp: November 17, 2016, 10:25:28 pm
content: Quote from: Bicurico on November 17, 2016, 10:17:47 pmActually that would be pretty good outcome.Few years ago I got a few stepper driver ICs by Toshiba. Had I not measured it's pins with multimeter (gut feeling helped), there would be an explosion and likely a handful of other parts burned. Turned out to be different stepper driver by Toshiba (not pin compatible) remarked. Or say power transistors. In PSU they may cause expensive device powered being destroyed. In audio amplifier, could cause entire output stage and speakers destroyed.

author: Bicurico
author_rank: Super Contributor
timestamp: November 17, 2016, 10:29:58 pm
content: You are right.But then, if one purchases spare electronic components, no matter where from, one should kind of know what they do and somehow check them first.For instance, I would not mess with a PSU using components which I do not trust.In my case, the already cheap device was dead and I had no way of getting original spare components (the device itself probably was using fake ones in the first place). So I had nothing to loose.Also, you mention it was a different stepper driver: may even not be a fake, then? And a mixup can happen at respectable distributors, too.Cheers,Vitor

author: wraper
author_rank: Unknown
timestamp: November 17, 2016, 10:56:30 pm
content: Quote from: Bicurico on November 17, 2016, 10:29:58 pmThat was older model, BJT vs MOSFET. They removed old marking made by paint and made a new one with laser. Both cost about the same on ebay/aliexpress, pure sabotage. As well I've seen a lot of remarked laptop GPUs, it's so huge that really difficult to receive what is actually purchased. Some of them work, some don't, some depend on motherboard you use it for.Also I've got remarked UV EPROMs, some seemingly had only date code and/or speed grade upgraded. Some had completely different die inside (same capacity). After figuring out what it originally was, turned out they are really old and need 25V programming voltage instead of 12.5V. The fun part was they all were ordered from the same seller with a few days difference. All of them had exactly the same marking, including date code.I's more of less ok to buy something that is hard to counterfeit, but you still cannot be 100% sure.

author: wraper
author_rank: Unknown
timestamp: November 17, 2016, 11:10:06 pm
content: http://www.thessdreview.com/daily-news/latest-buzz/manufacturer-shipped-review-sample-ssd-contains-fake-nand-flash-memory/3/

author: Bicurico
author_rank: Super Contributor
timestamp: November 17, 2016, 11:11:24 pm
content: eeeek!!!That is a bad ass counterfit component!

author: Siwastaja
author_rank: Super Contributor
timestamp: November 18, 2016, 03:59:51 pm
content: A $1 fake component can easily cause 100 lost hours and $100 worth of burned parts even for a hobbyist. This can easily lead to the total end of hobby.

author: Howardlong
author_rank: Super Contributor
timestamp: November 18, 2016, 05:43:35 pm
content: About six years ago I had a board assembled in China, and the assembler promised he'd purchase the precise parts specified on the BOM, from the distributors quoted. I did offer to issue him with the parts (having the concerns already cited) but he came up with excuses such as customs delays if I did that, so I relented.When I received the assembled boards, there were a number of errors, the most obvious were largely cosmetic, such as an SMA connector that didn't fit, and they tried to blame that on me at first until I reminded them of their unfulfilled promise to use the precise parts specified.The worst problem was that a low PSRR voltage regulator I'd specified had about a very high failure rate, about 30%, and the failure mode was to dump 5V onto a 1.5V rail. As you can imagine, that kind of failure on a 50c regulator cause quite a bit of damage elsewhere, as well as a lot of time required to perform fix and rework. (Under the microscope there was no visual difference between the failing part and a kosher one, so I suspect on this occasion they were using parts from a failed batch.)There response was to offer me a $50 reduction on my next order. Thanks, but no thanks!My point is that there is a different culture, and if you're a noob as I was, you'll be shafted. While you can make manufacturing and procurement work in China, you need to be there on the ground, seeing the whites of their eyes, or at least have someone you inherently trust and who knows what they're doing managing those business relationships for you. That's all very well, but that has a significant cost to it, frequently offsetting any perceived financial benefit of using China for production jobs, particularly on small to medium volume items.Interestingly, the Raspberry Pi foundation encountered an almost identical problem with their first batches in China about a year or so after my experiences, where the assembler used the wrong connector. I did try to warn them in advance of the sharp practices, but I would imagine they were very busy at that time. Like me, they moved their board assembly in the UK, a decision that speaks volumes (excuse the pun).

author: suicidaleggroll
author_rank: Super Contributor
timestamp: November 18, 2016, 09:53:39 pm
content: I buy no "new" electronic components from eBay/Ali unless I absolutely have to. A typical project has tens or hundreds of different parts, and at least 10 different ICs. If there are 10 ICs and each IC has a 50% chance of being fake because it was bought on eBay/Ali, then the chance that the entire assembled board has at least 1 fake is 1-.5^10 = 99.9%. Yes, a 0.1% chance that all parts are legitimate, and a 99.9% chance that at least one is fake, which in all likelyhood will cause problems with debugging, and possibly destroy the entire project. There's no way in hell I'm taking that chance, the fact thatanyonetakes that chance is beyond me. My time is more valuable to me than spending hours/days/weeks chasing down some erratic behavior being caused by a fake part that saved me $1.

author: M4trix
author_rank: Frequent Contributor
timestamp: November 18, 2016, 10:43:02 pm
content: Have no fear guys ! Mr. Donald Trump will bring back semiconductor manufacturers back to USA !

author: jasonbay13
author_rank: Contributor
timestamp: November 19, 2016, 04:28:21 am
content: i got a few lm317's from one seller and 338's from another. both probably counterfeit, but in the same application as my 317 from radioshack, it exploded instantly. next one worked for a few seconds before shorting out. replaced with radioshack one again and all was working fine. the 338's work fine though.i wonder about those pre-built circuit boards. i've had good luck with those things, cheap and unreliable but they do work as long as you dont short them, or let them get hot, or go near the advertised limits.them batteries are the worst, advertising brand name and 10x capacity batteries.

author: ZeTeX
author_rank: Frequent Contributor
timestamp: November 19, 2016, 08:35:09 pm
content: 6Ah 18650 single cell battery on aliexpress.. yeah sure, the Chinese people have made the most dense 18650 in the world for 1$!!

author: CraigHB
author_rank: Regular Contributor
timestamp: November 20, 2016, 04:30:32 pm
content: Quote from: M4trix on November 18, 2016, 10:43:02 pmHaha, after he fires China.China...you're fired.

author: CraigHB
author_rank: Regular Contributor
timestamp: November 20, 2016, 04:42:45 pm
content: Quote from: ZeTeX on November 19, 2016, 08:35:09 pmAnd the thing is people believe that crap. I don't know how times I've mentioned don't buy batteries with grossly over stated capacity. I mean is it worth risking an 18650 blowing up in one's face. It's unbelievable the lengths unscrupulous sellers will go to with bogus 18650s. They even go so far as to buy factory rejects sold for recycling and put counterfeit labels on them. What makes it worse is they'll copy brand name labels so you think you're getting a genuine brand name battery when it could actually be a hazard in a can.

author: wraper
author_rank: Unknown
timestamp: November 20, 2016, 05:09:28 pm
content: So here is my personal experience. ATTINY24 grinded, blacktopped and remarked as ATTINY24A, few of them are actually ATTINT24A with newer date code marked. Same date code on top, different date codes on the bottom. They work fine but consume more current than ATTINY24A, and as they are pretty old, solderability is not very good. Genuine IC for comparison.BTW both are from China and purchased at the same price from different sellers.

author: 4cx10000
author_rank: Regular Contributor
timestamp: December 18, 2016, 12:58:48 am
content: Hi!I am about to build a high power dummy load with 100W resistors: 2, 4 and 8 ohms. Has anyone tried any of those China high wattage resistors? They look pretty much as the ones Farnell's stock, but cost is $16 each compared to Ebay price $1.5I do not want to order them if they suddenly go up in smoke at half theirs power rating...I have been in repair business for at least 30 years and remember very well when first counterfeits came on the market. That was a brutal attack on my self confidence seeing components blow up without a reason. These days I am very careful when it comes to order components so it goes to Farnell, RS and Elfa. BTW, here is a link to the Ebay resistors I was writing about and would you dare?http://www.ebay.com/itm/1-2-4-8-10-Ohm-100W-Watt-Shell-Power-Aluminum-Housed-Case-Wirewound-Resistor-New-/141957695607?var=&hash=item210d568877:m:mTihmKm-hBqIO03-aYwyRmw

author: Spikee
author_rank: Frequent Contributor
timestamp: December 18, 2016, 01:52:38 am
content: China has some amazing prices. The company I work with is in china (for like 15 years) they source everything from gray markets / taoboa.This is voor 1000-5000 QTY of designs. The reason they do this is because parts are so much cheaper.TI CC2540 is around 8RMB; even at 10k qty I can't find a single distributor that sells it for less than15RMB. this is why this method of chip sourcing can give you such and competitieve advantage.I have never actually asked where they source it from. I assume that there are companies who stock all these genuine components and work as some kind of gray market distributor. AFAIK they never had an issue with fake parts before.

author: TheDane
author_rank: Regular Contributor
timestamp: December 18, 2016, 03:19:08 pm
content: Having purchasedsomestuff from China, I can so far say I've been 'burned' on a supercap deal where the seller sent some old broken units.Some items have been poorly wrapped for shipping, and I've seen rheostats been broken/cracked that way. Oh well, they're cheap - but they work after a bit of glue, or if cracked entirely the seller has re-sent the item. I haven't tested them with a full 25W load though, but the unit seems fully capable.Do not expect much, and test the items before you ramp up - that's the price you pay, when wanting the items for less than 'retail'.And - Do NOT use stuff you do not trust for mission critical projects!!!Don't buy the cheapest, and use the datasheet to identify device codes/id's - and if possible compare to sellers picture online.(Samples and large volume orders - two different things, build up trust with one seller - and make sure you get purchase protection, in case you're had)Respect - and you get respect. Be firm, and you get good business

author: 4cx10000
author_rank: Regular Contributor
timestamp: December 18, 2016, 05:35:05 pm
content: I will order those high power resistors as the money involved wont hurt if they go up in smoke - I will let you know how it goes. I bought a rifle scope couple of years ago from China - Leupold clone - and when it finally came, after two month delivery time, it was like a banana in shape because of bad packaging. It did not cost much but had no intentions to mount it on my rifle since there where a great amount of chance to shot my self in the butt... Sent it back and got one in return and in good condition, but of course, it cannot be compared with the original. Well, that was a bit out of subject ... sorry

author: MartinX
author_rank: Regular Contributor
timestamp: December 18, 2016, 10:03:00 pm
content: The counterfeiters are particularly aggressive when it comes to audio components, on eBay you can get a seemingly endless supply of Toshiba and Sanken and Motorola output transistors, even the types that have been out of production for 15 years! Electrolytic capacitors are just as bad, Elna and Rubycon made a lot of special audio types some long out of production but the stock of the eBay sellers replenish forever.If you by audio components from Chinese eBay sellers the risk of buying fake components are close to 100%

author: Tomorokoshi
author_rank: Super Contributor
timestamp: December 18, 2016, 11:05:31 pm
content: If you have a band saw or a milling machine, buy a few extra resistors and slice them apart.

author: rolycat
author_rank: Super Contributor
timestamp: December 18, 2016, 11:14:12 pm
content: Quote from: ZeTeX on November 19, 2016, 08:35:09 pmThat's yesterday's capacity. Thanks to the white heat of Chineseexaggerationinnovation, 12000mAh cells are now available. These little gems are $1.28 each:Although asthe vendorthoughtfully warns, theycanfire a series of disasters:

author: 4cx10000
author_rank: Regular Contributor
timestamp: December 18, 2016, 11:19:37 pm
content: TomorokoshiQuoteYou bet I will, we got all that at work! I ordered 4 extra of each value - 2 and 4 ohms. I will use my power supply - TTi CPX400D - to make a quick test as well, lets see what happens.

author: CraigHB
author_rank: Regular Contributor
timestamp: December 29, 2016, 06:18:27 pm
content: Quote from: rolycat on December 18, 2016, 11:14:12 pmI'd like to see that one on a test rig, be lucky to see 1200mAh let alone 12,000. My sister recently bought one of those power banks for charging phones and stuff from China. It had 50,000mAh printed on it. Yeah right, 5000mAh would probably be actual. An order of magnitude goes way beyond exaggeration.

author: ICsAPA
author_rank: Newbie
timestamp: July 05, 2017, 06:41:55 pm
content: Recently purchased some parts via eBay sourced from china, DFLS1100-7. Parts arrived and I noticed they came on a new reel with clear tape rather than anti static tape, the label did no match in layout or information the manufacture's el specs, so to make certain I brought these & known originals to a test house for X-ray comparison. The images did not match. (See attachment)I contacted seller to explain. The seller stated with absolute confidence "don't worry parts will work". I am pretty sure this was said because the seller truly thinks the parts they delivered were original even though they clearly were not. 99.9 percent of these Chinese sellers brokers distributors" have little to no quality control, no and anti static protection program. Some parts they sell may initially function and continue to function until such time when they fail because they encounter an event the original was designed to handle but the fake downgraded part was unable to withstand.Most components coming through the grey market from China are not original and as I stated earlier the sellers don't even know it. I have a friend who works as a professional buyer of electronic components who told me as of a few years ago that they completely stopped buying from grey market in China because over 85% of what they received were unable to pass incoming inspection, code words for fake.An earlier post suggested that one of the message to determine whether a part was fake was based on the price. the post suggested if the price was close to reasonable the likelihood that the item was a fake would be low & if the price very low then the likelihood was very high the item would be fake. In my experience this is not valid. I have had great success buying on eBay from a USA based seller componenttradersllc they have never sold me a fake and I have gotten some great deals.Sent from my iPad using Tapatalk