The don't fake JFETs now.......do they?

[duck_arse]

those ^ legs are a real mess. very un-fairchild-like.

[rockola]

I recently purchased some 2N5484 from adeleparts2010 off eBay. They measure IDSS of 32uA@15V (yes that is correct) versus minimum spec of 1mA, and VGS off of -600mV. In a standard common source configuration with VDD = 15V, RD = 47k, RS = 10k, RG = 1M (to gnd), the VGS forward biases to 0.6V. It should typically be negative biased to around 1 - 1.5V in this circuit.

I don't know what these parts are, but they are most certainly not 2N5484s.

Nothing has changed. Against my better knowledge I purchased 10x 2N5457 and 5x 2N5484 from adeleparts2010 in December. None worked. They did issue a refund when I complained.

I built two test rigs, RG's and the "new improved" one, to check these out. I also had some 2N5457 from Mouser, and from an earlier eBay order (don't remember the vendor, this would have been years ago). The old eBay 2N5457s look exactly like the ones I now received (Fairchild stamp, no letter in the back, etc.) - except they seem to be genuine. (I also had a bag from yet another ancient eBay deal which was full of fakes. Oh well.) The values were in the same range as the ones from Mouser (which have an Onsemi stamp). However, of the whole bunch (maybe 40 working JFETs all up) only two measured Vgs >-1.0V, with the majority being in the -0.6V...-0.8V range. I only ran the new batch through the "new improved" matcher so don't know (yet) how these would have behaved with that one. I'm now left wondering what to make of this (and what to make with these).

[italianguy63]

Recently got fake 2N5458's from eBay (China).  But, now have a good stash of real old-stock Motorola's.

MC

[megavolt]

Hi,

first post here 

Stumbled across this thread via google, only a reading member up to now...

Bought several ICs from ebay, and nearly all of them were fakes, sellers were the last two mentioned here, pol* and adel*. Voltage doublers, standard ICs (LM 833 e.g.), LM308, MN3008, all sanded, reprinted. The voltage doublers double nevertheless, the op amps work, although I did not compare to the same model from a reliable source yet. None of the MN3008 worked. ICs sold as new were clearly desoldered. All J201 I got from those sources seem to be fakes. All these sellers had a good reputation at ebay. I had left a positive feedback before I even noticed what junk I got, possibly others did the same.

My advice is to stay clear from these sellers mentioned above. Perhaps they do not even know what rubbish they sell, but they do not care either.

[Rob Strand]

We need a fake sellers list on this forum.

[merlinb]

Even surface mount JFETs are going obsolete now. Seems the world doesn't want to use them anymore. We're very worried at work.
https://media.digikey.com/pdf/PCNs/Vishay/PCN-SIL-0052008%20Rev%202.pdf

[Kevin Mitchell]

On the subject of creating a list of bad vendors...

adeleparts2010 on ebay had sold me a load of fake B245B.
So far that's the only fake part that I've received in my few years of DIY electronics and also my only purchase with that vendor. In a circuit with over 600 parts this bastard stumped me for over a month.

[tubegeek]

Ahhh shit. 50 pieces of 2N5485 from adeleparts2010 are testing weirdly - 0 for Vp in the simple JFET tester.

So that's the explanation then?

Let me see if I can get my money back. Damn it. Wish I had seen this thread before purchasing. Thanks gents.

Here are the details for this seller that come up when I request return/refund.

ZhenYi Chen
1914,Wanke Huizhi Center,Changhua Road, Wuhou District
Cheng Du, 四川省, 610045

[Kevin Mitchell]

Ahhh shit. 50 pieces of 2N5485 from adeleparts2010 are testing weirdly - 0 for Vp in the simple JFET tester.

So that's the explanation then?

Let me see if I can get my money back. Damn it. Wish I had seen this thread before purchasing. Thanks gents.

Yeah they're bastards for sure.

I seem to have better luck using UTSOURCE for obsolete parts. Though often I'll receive desoldered/used ICs. No big deal - as long as they work and the price was reasonable to offset the chance of bad ones being in the batch.

-KM

[tubegeek]

Quickly received a refund for $10.52 on a 13.24 transaction.

Out 2.72, not the end of the world (probably deducted the shipping and their fee.) I've requested that they issue a refund for the balance, I don't care that they got hit with those costs, they're selling counterfeit parts for crying out loud.

But I'm at least not out that much at this point.

Of course I'll negative feedback once all is said and done. Bastards.

[Govmnt_Lacky]

Of course I'll negative feedback once all is said and done. Bastards.

Did they restore that feature?

I ask because I remember LONG ago when I received some bad items from a seller, I filed a complaint through eBay and ended up getting refunded. When I went back to leave feedback about the transaction, I was told (by EBay) that I could not leave a (negative) feedback since the seller refunded. Seemed stupid to me but that was what I was told.

[tubegeek]

Did they restore that feature?

I guess we'll see! I "escalated" the refund complaint - Merry Christmas, adeleparts2010! - and asked for the rest of my money. No way should I pay for shipping of an item that's not as advertised - I believe the UCC (Uniform Commercial Code) has my back on this, but that's a US law and it's a Chinese seller so....

Trade wars are good, and easy to win, or so I hear.

[merlinb]

FYI Central Semiconductor have recently redesigned all their JFET masks to ensure long term supply.
Here's the JFETs Parametric Search section on their website.
https://my.centralsemi.com/paraSearch/parametricSearch_v1_1.php?task=bldPartTable2&PGroup=30&subGroup=10

[tubegeek]

FYI Central ...

Stingy with free samples apparently though

But good info and good news thanks!

[mac]

I just bought a few BF245B Fairchild from an elect store near my apt which has been my main source for years.
These "fets" are nice low gain NPNs for a Fuzz Face 

mac