Rick C <
gnuarm.del...@gmail.com> wrote:
> On Friday, January 20, 2023 at 8:58:49 PM UTC-5,
anti...@math.uni.wroc.pl wrote:
> > Rick C <
gnuarm.del...@gmail.com> wrote:
> > > On Friday, January 20, 2023 at 4:02:27 PM UTC-5, Dimiter wrote:
> > > > On 1/20/2023 22:37, Rick C wrote:
> > > > > On Friday, January 20, 2023 at 1:17:59 PM UTC-5, Herbert Kleebauer wrote:
> > > > >> On 19.01.2023 19:06, Rick C wrote:
<snip>
> > > My experience with Alibaba is not the same as yours. With Ebay, I can dispute a sale and get a refund. Alibaba spent literally months demanding more and more things from me, many which made no sense because of the language barrier. In the end, they said I failed to prove the vendor was lying when he said he shipped the item listed. Photos were not good enough. They wanted a video for some reason. Alibaba simply does not support their customers, so I don't use them. Ebay is worth while, but some things sold are perpetually fake, or crap and you have to buy them to find out, then make the "return", which the vendor is required to pay for, so they often say keep it.
> > >
> > > I even bought crap wire on Ebay from a vendor relatively local. The actual wire gauge was about three numbers below the claimed AWG. Bought 20 gauge and got 23 gauge. Bought 18 gauge and got 21 gauge, etc. I was getting the refund, so I thought I'd try seeing how far this went. 16 gauge was actually 19 gauge and 12 gauge, was actually 15 gauge. The vendor could not say they didn't know, the wire insulation has *their* name on it! So it's a custom marked product. How could they not know they are selling mislabeled wire?
> > >
> > > Yeah, they all sell crap. I just find it possible to get a refund from Ebay. Alibaba, not so much.
> > >
> > IIUC Alibaba is intended for larger transactions and has different
<snip>
> No, they send something, just not anything of value. Aliexpress can't seem to understand the ICs which don't work, are counterfeit and you don't have to test every one on the reel to know they are all crap. The real issue was the language barrier. They don't speak English, rather use automated translators in both directions, so don't understand half of what you are saying. They also don't understand what an IC is and think counterfeit is only for handbags.
My impression was that verndors understood resonably well what I
wrote and answered sensibly. The things were probably too small to
really involve a person from Aliexpress, communication from
Aliexpress looked like canned text. So really no big problem with
Engish, but potentially could be different if matters got more
complicated (more value at stake and vendor contradicting my claims).
BTW: Aliexpress want very much to translate offers into my native
Polish. Compared to English text that they have translations into
Polish are really funny/misleading.
> > Most Aliexpress seller have resonably high volumes. They sell
> > what customers want to buy. It can not be completely non functional,
> > there are not enough fools to support this.
>
> LOL! If they buy counterfeit ICs at $0.05 each, they don't need to sell many at $5.00 to make profit.
In general, probably 1 in 100 customers makes comments dealing with
actual performance of given product. So after 100 sales, if thing is
non-functional you can expect bad opinion and after that more folks
looking at what they get and cascade of more bad opinions. Actually
if thing is completely non-functional I would expect complaints
much earlier. So maybe bad guy can collect few hundreds or maybe
some thousends dollars. If one could do such thing without a cost,
then surely, there would be a lot of folks doing this. But there
is probably some cost setting Aliexpress seller account and if
enetrprise is pure fraud, then Aliexpress is likely to take some
action (say via court or police).
My impression is that complete, pure fraud is not big problem.
Rather, problematic are goods that appear to work but are substandard
or have hidden defects.
> > The problem is
> > that most customers are unable or unwillig to fully examine
> > what they bought. So you get rechargable batteries with
> > completely bogus stated capacity or USB chargers with inflated
> > charging current. I bought a lot of things on Aliexpress
> > but I am trying to keep realistic expectations. I bought
> > few USB chargers knowing that stated current (2.1 A) is
> > much bigger than real one (0.85 A), but they were good enough
> > for my purpose. I bought resistors and small power transistors.
> > My reasoning was that making something that looks like resistor
> > or transistor in small/medium volume is probably more expensive
> > than real resistor/transistor in high volume. And hopefully
> > there are not enough fools to fund high volume manufacturing
> > of fake transistors.
>
> I don't think you understand. There are any number of things that look like the thing they are selling you, which will pass a visual inspection if you close one eye and have no idea what you are looking for. But they are fake. Even a $0.10 transistor has a lot of markup if they only pay $0.001 each for a reject. It might work well enough to light the LED on a transistor tester.
I was writing about basic transitors like 2N3904, BC237 and similar.
AFAICS $0.10 for such transistor is well above market price. Few
years ago 2N3904 from big American distributor was $0.0234 per piece when
you wanted 500. About 10 years ago reputable local distributor had
basic types for equivelent of $0.015 per piece in quantities of 100.
And BF493 was half of that. This distributor had a warehouse and
same day (if order was early enough in the day) or next day shipping.
Chinese seller had batches of 100, with prices of order $1 per batch,
that is $0.01 per transitor. I was a bit curious so I looked at
availability numbers. Apparently he started from 10000 and counter
went relatively fast down. And then restarted from 10000. So
he was selling milions of transitors (10000 times 100 is milion).
I also looked at Farnell. For similar type they had something like
35000 and counters were slowly changing. So Chinese guy had _much_
larger volume than Farnell and almost surely much lower operating cost.
At prices between $0.10 and $0.20 per piece I got few TO-220
powers MOSFETS. They were out of specs and probably rejects:
both Rds_on and junction capacitance was larger than it should
be, so this was not smaller MOSFET relabeled as bigger one.
I consider them good enough for undemanding uses in experimental
circuits. Certainly I would not allow them to get anywhere
near production (too much risk that they would end up in
critical circuits).
> > Well, I got resistors and resonably
> > performing transistors. I can not say if there are some hidden
> > troubles but to the moment I am satisfied with what I bought.
>
> Sure, if you only need crap components, then you are good to go!
If I had extreme requirements, then I would not use 2N3904 or
BC237. But they are good enough for most uses.
> > In the past I bought few STM chips from Chinese sellers.
> > AFAIK those chips were widely used in China, the unit price was
> > much lower than unit price from western distributors, but
> > significantly higher that supposed volume price. So it
> > looked resonable that Chinese seller could sell them at lower
> > margin and still make a profit. And up to now I had no
> > problem with those chips.
> >
> > OTOH if there is advanced/rare western part it would be strange
> > if Chinese seller had some magic cheap source of the part, so
> > I am very suspicious of such offers. Power mosfets were
> > borderline case. Around 2019 I bought packs of 10 from several
> > sellers. Essentially all were out of specs (too large Rds_on). If
> > there were moderate discrepancy I made comments stating real paramenter,
> > in few cases of really large discrepancy I requested partial
> > refund (and got it possibly after a dispute). To say the truth,
> > refunds that I got were probably not worth my time, I did this
> > mostly from feeling of moral duty, to make sure sellers know
> > that there is problem and to discourage them from selling such
> > bad parts.
> >
> > When buying on Aliexpress it is useful to read buyers comments.
> > Especially Russians tend to measure/test bought parts, so you
> > can have resonable idea what you are buying.
>
> I've never found any selling sites with good reviews. Many are made up from whole cloth. I recall when Ebay had some sort of rating system in both directions. There were vendors who would set up buyer accounts and buy things at a penny. Good reviews in both directions and credibility would increase.
There may be something like that at Aliexpress. But I meant actual
text of comments. It would take some effort to make up text that
is belivable and it is not clear what seller would gain. Aliexpress
allow you to view opinions corresponding to given rating, so you
can look up why people give bad rating (while good ratings frequently
came with no text, bad ones usually give some justification).
> Eventually Ebay put an end to it, partly by all but eliminating reviews of buyers. Now, I find very few sellers with fewer than thousands of ratings. If they have few ratings, or are below 99% positive, I avoid them if I have choice. One thing I've learned is to completely avoid flash drives on any of these sites. 90% of the time, they will fail a good memory test. Seems they use a flash drive 8 or 16 times smaller and flip the bits on the size reporting. They can sell a bunch of these before they are booted off the service.
I never looked at flash drives online. I bought SD cards and at some
time there was flood of fake cards that reported much higher capacity
than they had. But then came programs that tested real capacity
and it seems that problem essentialy vanished. At least for
moderate capacities.
--
Waldek Hebisch