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| Claimed "1/4 watt" through-hole resistors from Amazon seller "Eamasawa" |
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| eti:
--- Quote from: tkamiya on September 17, 2020, 03:25:19 am ---Ha! Someone with the same concerns as I... I've purchased registers from Amazon, too, and were quite surprised how thin the wires were. So far, for building purposes, they made zero difference. Wires form easily and hold shape. I never push 1/4 watt registers to the limit anyway. I think they are the result of cost cutting measure. Some dealers (like SparkFun) are starting to label their products as "thick lead" to differentiate from these. I'm so surprised at the length some manufacturers in China would go to cut cost. More concerning are their fuse holders. Some "18 gauge wire" looks like 22 gauge. Yet, spec'd at 15 or 20Amp. Some are now saying "real 18 gauge wire" in their ads. These days, for things that matter, I buy from Digikey. For ones they don't, eBay or Amazon will do. I hope Amazon will recognize being a conduit for these substandard parts will reduce them to second rate merchant, and affect future growth. Somehow, I doubt that will ever happen. --- End quote --- I hope Amazon will recognize being a conduit for these substandard parts will reduce them to second rate merchant, and affect future growth. Somehow, I doubt that will ever happen. Oh I believe they've been right down there at the very dregs of the barrel for a lonnnnnnnnnng time. They're the cheesiest, tackiest, most unethical, cheapest and lowest common denominator losers in all of retail. People can't seem to see past "cheap" and so people believe (falsely) that they "love Amazon" - no, they love being pandered to and being lazy, convenience-driven sheep that buy any old tat because it magically appears on their doorstep in 12 hours (and then flood eBay with it 6 months later, once they have played played with their little toy and then shoved it in a drawer somewhere). Amazon are literally the lowest of the lowest of the low, the bottom feeders. They disgust me, despite my using them rarely. Jeff Bezos is on the same planet that he and Elon "highly and disturbingly, and I think I'm changing the world" Musk, IE, definitely not planet earth. If ever there needed to be textbook examples of power going to one's head and disturbingly distorting your perception of reality, these two lads epitomise how NOT to be a responsible, adult, sane and kind CEO. |
| coppercone2:
first of all, their not right, they are weak. I have damaged them doing circuit repairs that would be fine with normal resistors, particularly bending them out of the way. Package engineering is HUGE and its dictated by COST. They made it cheaper not better, you can make garbage run for a while. And again, it does not work on breadboards well, its not good for hobbyists. It's not fine for manufacturing either, because then you should specify a real 1/6 watt resistor if you need less power lol how to avoid scams? Look up 'resistor manufacturers' on google. They will give you a datasheet btw amazon is not a great company and not a great employer.. not sure you should associate with them on stuff that is a known problem. I should do a side by side over load test to see how they burn up compared to each other to see if the core is the same. Connect both and ramp up the wattage to see which one goes first, and how it goes, then do a pulse over load test to see the failure mode there (explosion characteristics, to see how much it will damage the circuit its in) I also have a hunch the leads are not electronics grade oxygen free pure copper, more like recycled pipe fittings. Another test you can do is get a real 1/6 or 1/8 watt part that has the same diameter lead, and then do a back and forth bend test to see which lead breaks faster. This also messes with the temperature coefficient of the device I think, so if you do the whole precise matching thing, you might be frustrated with drifty results if you think you can get a precision circuit on the cheap. Also the plating might be low quality, so it could make solder joints brittle. I also noticed the epoxy coating or whatever is more fragile on the cheap ones, they tend to fracture the ends when you bend them, this is a recipe for low moisture immunity and stuff if it compromises the package during part fitting prior to soldering. Then you might also want to test the paint, see how the marking paint holds up to elevated circuit temperatures, to see how repairable the part will be if it runs hot, fades the paint, then burn out, so you are left with a unlabeled dud in the circuit. Good resistors often burn out but still have legible markings. and when I measured them, their TCR is all over the place as compared to factory made resistors, which do much better then the datasheet usually, when comparing metal film to metal film. Batches do not line up, meaning unstable deposition I think, possibly also meaning poor film adhesion and low reliability. |
| Simon:
I bought boxes of 5'000 resistors from china at one point and yes the wires were a bit thinner, not a problem really I just noted that they were not what I had bought before but when you think of the total accumulation of material used and weight to ship it's not a bad thing so long as they remain fit for purpose. |
| MosherIV:
Hi The simple solution is just do not buy electronic components from Amazon or Ebay! You just do not know what you are goinb to get. There are plenty of reputable suppliers in the UK. Farnell and RS now sell to individuals but be aware they have a charge for postage if the order is below a minimum amount. Also look at RapidOnline and CPC. Then Mouser and Digikey do ship to UK. I use a small company called Bitsbox.co.uk To be honest, they all either have postage charges or only give free postage above a minimum order amount. |
| HobGoblyn:
As my wife has Amazon prime, it can be very handy ordering something at 9pm and get next day delivery. Needed a small length of 16 AWG silicone wire for my 3D printer, having it here the next day, was worth the £6.98 For 10ft. Farrell want £2.98 (plus 20% vat) per meter then there’s £5.95 delivery on top. When setting up my lab (only been doing this hobby a short while), the cheapish Chinese books of 0805 SMD resistors, the cheap sets of electrolyte caps, transistors and voltage regs I got from Amazon, are perfectly fine for my learning. That said, when I needed to replace a cap recently I didn’t use one from the cheap set, I got one from RS. I have noticed that Amazon has a lot of dodgy looking goods from 3rd parties on it, it also has a ton of incorrect descriptions from them where unless you read the entire spool of text, you probably won’t be getting what you think you’re getting. Sometimes there’s reviews pointing this out that are over a year or more old, but it’s still incorrect today. On Aug 24th I ordered Araldite Epoxy from Amazon, the title said “Araldite ARA-00007 Epoxy, Set of 6”. Looking at the price I knew it was only going to be 1, not 6. (but you never know). Sure enough only 1. Rather than complain in the reviews, I decided to try clicking on the “Report incorrect product information” and explained. I just clicked on same page, now the “set of 6” has been removed. The Amazon reviews are also usually pointless (99% positive etc) but reading the few negative reviews can give me an opinion of whether the fault is with the buyer (giving bad review because the don’t know what they are doing), or whether it’s total crap. |
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