[JamesBryant]

But don't waste time reinventing the wheel. I needed a small audio amplifier the other day and looked for an IC to build it. My junk box was empty of audio amplifiers so I went to a distributor and found a nice IC for 65p but minimum order 10 off. With postage the price was about £10, and I still had to find the other components and build it.

I was just about to order it when I realised it might be cheaper on eBay. There a found an assembled board with the same amplifier for 56p with a minimum order of 5 pieces:- £2.80 post paid and ready to use - and four spare ready-made amps for future projects.

Beating the system is fun, too.

[kevin_thibedeau]

The eBay sourced chips are likely counterfeits that won't meet all the specs.

[omgwtfbyobbq]

In my experience the random stuff I buy off of whatever $Auction_Site seems identical to what I buy from $Local_Vendor, but with no QA or packaging. The defect/failure rate is higher and it takes a lot more time to arrive, but the cost is significantly less.

It's possible that there are more counterfeits, but I don't think the stuff off of $Auction_Site is likely (>50% chance) to be a counterfeit just because it's from $Auction_Site.

[kevin_thibedeau]

If it's a chip that you can search for in a product description it has a high enough profile to be an SZ fake. See this example of a fake signal gen IC that almost works properly:

https://www.youtube.com/watch?v=02XtneCHnDA

Add in a price that's too good to be true and the odds go up.

[omgwtfbyobbq]

I can see that. I've purchased several laptop batteries that likely used old cells pulled from another laptop or whatever. At the same time, I don't mind that the runtime is a 1/2 to 3/4 of a new battery when the price is 1/5 of a new battery.