At .06 each, you can afford to just build up a simple circuit and see if it performs as expected. I have gotten “bad” TO-92s before, out of a bin of loose parts with mixed brands. No idea if they were counterfeit or just mismarked. It was a PNP when it was supposed to be an NPN. It was only a handful out of a couple hundred - I just tossed the ones that looked like it. The rest were fine. Were any of them real? In the circuit it didn’t really matter.
Why we make a big stink over counterfeit power transistors is because they can go up in flames, and they do show up all the time. The likelihood of getting a fake is exponentially related to the normal selling price and goes off the scale if there is no legitimate source. For jellybean parts it is less likely, but can happen. A circuit using a BC546 probably won’t have a safety issue. If it’s bad it just won’t work. Being noisy or low gain comes under that umbrella. Then you spend more and get good ones. For something mission critical you don’t take the chance. But there are a lot of times where almost anything would work.
Why we make a big stink over counterfeit power transistors is because they can go up in flames, and they do show up all the time. The likelihood of getting a fake is exponentially related to the normal selling price and goes off the scale if there is no legitimate source. For jellybean parts it is less likely, but can happen. A circuit using a BC546 probably won’t have a safety issue. If it’s bad it just won’t work. Being noisy or low gain comes under that umbrella. Then you spend more and get good ones. For something mission critical you don’t take the chance. But there are a lot of times where almost anything would work.
Thnks for the advice. Probably they'll work fine but i need some 'good' 546b for differential pair, so noise, gain and matching are quite important here. I think you can understand what i'm trying to say. The sad thing is, here in india RS sell some very common but essential components in bulk quantity, i don't know why the do so?
Although their price is little high but i'm comfortable with that because component quality is assured. Mouser is not a option here because of their high shipping rate, so my only option is local component stores. You may not believe but they sell authentic 3886tf for only $3 and tl074 for $0.15! So still there is a hope 🙂 Although I have to search many stores, because mostly they sell are of low quality cheap components. India is not a great place for audio related components and for hobbyist like me.We don’t have much in the way of “local components stores” here - unless you want to pay $3 each for NTE123AP. We had two local surplus shops, but one closed up shop and the other hasn’t gotten new inventory since the start of the pandemic. Pretty much everything going forward is going to be regular distributors. I did spend the last 3 or 4 years building a huge inventory to last the next 20 or 30 - mainly because what I use is rapidly disappearing, and I expect money to be tighter and tighter over time. When thru hole parts go away entirely, the likelihood of fakes will hit 99% - even for 6 cent parts, and making circuit boards at home will become almost impossible requiring either an offshore order or a $500 board run domestically just to make the simplest of circuits. Soon there won’t be any place in the world that’s good for the audio hobby unless you have gobs of money to throw at it. I doubt I’ll ever have a pick and place machine and a proper reflow setup - but that’s where it’s going.