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

[PRR]

> How are FETS manufactured? Are they manufactured and then sorted and labelled based on their specs or does a manufacturer make a batch of J201's.

There are a dozen basic "masks". Skinny channel for low leakage, fat channel for low resistance.

There is a small range of processing. Kinda like you can cook cookies for 7 minutes soft or 9 minutes crunchy.

There are several packages.

There are 98,765 different part-numbers. Even discounting same part in metal plastic SMD, and insignificant differences, there's thousands of electrically different part numbers.

So yeah: they load "Mask 55", they bake 7.6 minutes, and they get FETs from Vgs from 0.3V to 10V, Idss from 0.3mA to 20mA.

If they have an order for J201, they sort-out some with 0.3-1.5V and 0.2-1.0mA, check the other specs like gate leakage (mostly controlled by mask and baking, but some high-spec part numbers might have to be sub-sorted), and put them in a bin. BUT if they have an order for private-number 08642BA, which might be a J201 except 50V breakdown for a dollar more, they will check breakdown and sell the 50+V parts under the higher-price part-number.

> wonder if they aren't some other "cheaper" jfet

All the "small" FETs are the same core price (the low-resistance FETs do cost more). And packaging costs more than the die.

However there's some go-to part numbers in high demand, and other part numbers which could do the same work but don't get selected very often. In general, raw FETs are not part-numbered until an order is being filled, so there won't be an over-stock of some unloved part number. Still there's lots of half-barrels of FETs with part numbers nobody is looking for.

And yes re-marking has become rampant. It's just a form of printing. Who invented printing? Folks in and around China (Gutenberg was a copycat). What is one of the MOST common manufacturing machines? Part-number printers. Everything from cereal bowls to car parts has a number. You can probably buy a small parts printer in those industrial towns easier than I could buy a boat (I passed 11 boats for sale coming back from supper).

Get your parts from *reputable* vendors. DigiKey and Mouser are super-safe. They both do so much business with Fairchild (or whoever) that they won't knowingly buy fakes. Some big distributor got burned (I think on fake CPUs!) so all the solid vendors are on the lookout. SmallBear is also safe: while he has been sold a fake or two, he gets right on it and makes it right.

There IS a long tradition of very lowest price purchasing. Radio manufacturers had buyers who would haunt odd surplus and failed businesses to save a part-cent per resistor. Those radios often hardly made their 30-day warranty. That's OK for a fly-by-night radio maker. It's a very poor example for hand-made personal or boutique pedals.

[haveyouseenhim]

Good news for me. I finally got a refund from polida. That dern chinaman needs to learn a lil more english if hes going to sell things to english speaking countries.  It was a nightmare dealing with that guy.

[garcho]

I like reading about how components are made, it's fascinating, thanks PRR. And I dig that we're watching out for each other, being a bunch of broke-asses looking for deals.

But...

WARNING, THE FOLLOWING CONTAINS OPINIONS. IF YOU DON'T LIKE OPINIONS, DON'T READ IT:

That dern chinaman needs to learn a lil more english if hes going to sell things to english speaking countries.

Hey, aren't you a Southerner? 

I find this thread kinda sad for a number of reasons. First, and most importantly, it's ridiculous that we live in a world so desperate and cynical that we rip each other off for peanuts; I'm so sorry you guys have been burned, what BS, really pisses me off, I love this online community and hate seeing hard working builders get ripped off.
Second, it's too bad that we're not doing much DIY SMD. That would make a lot of sourcing way easier.
Third, iPhones are made in China, and it's been MANY YEARS since I bought some mass-fabbed thing that was so well crafted. So, as my grandpappy said, 'can't all be bad'.
Fourth, don't like cheap crap from China? Then buy expensive crap from the States. Whenever people complain about 'hipsters buying organic' and 'boutique prices' and stuff like that, then turn around and complain about cheap crap from China it drives me nuts. If you don't want to buy from Small Bear et al. then buy cheap crap from across the ocean; no sympathy for the devil. Think you can have local, fair and cheap? Try visiting Europe for a little dose of reality. EVERYTHING is expensive. Except beer. We need to learn how to live with less, like adults. Impossible, I know.
Fifth, the US lost industry because of Americans who run gigantic companies who don't care about the consequences their actions have for the rest of us, tax loopholes and corporate welfare thanks to Congressmen selling their souls to lobbyists, and because of the rampant corruption of the totally f'd up Chinese government, not because of the 'wily Chinaman', or some grand conspiracy. That, and we decided as a nation a long time ago that we care more about quantity than quality.
Sixth, there's nothing inherently good about stuff made in the States, at least, not for the last few decades. We've certainly made our fair share of crappy plastic junk that breaks right away. In fact, along with the Japanese, we invented that.
Seventh, and I don't know about yous guys, but in Chicago, I'd trust a Chinese ebay seller at least as much as a general contractor, McDonalds, or a Boeing administrator. I think we assume Chinese sellers are sly before we give them a chance. And ask yourself, if people in China, or Sweden, or Botswana wanted to buy your pedals, would you learn their languages? Yeah right. No one has it easier when it comes to communication than native English speakers, even if they are from the South. Have a little compassion you hard asses! 

off topic:

And Paul, I agree the pollution is sick and out of hand, but somehow, being 1/4 the population of China, we still pollute almost as much. According to Reuters' sources, China produces 6 billion tonnes of carbon waste, the US produces 5 billion. Have you ever been to Houston, Hoboken, or Gary Indiana? They're not as bad as major Chinese cities, but only because they're not as big. Next up is Russia, with 1.5 billion. Not exactly holier than thou, ya know?

rant over, back to schematics!

[haveyouseenhim]

Oh c'mon. What I said was a jab at southerners. I'm not racist by any stretch of the imagination.

If I were selling to sweden, china, or north korea I would at least use google translate.  I don't assume anything about a seller until they do me wrong. this guy was shiesty and wanted to buy positive feedback from me

[garcho]

I know, that's why I was ribbin' ya dude, relax! I come from Chicago, we have horrible, horrible accents, and lots of racists of all colors and creeds.

I'm not disputing your story either, just sayin' online gear forums are rife with China hate that goes a little overboard, IM[not so]HO.

[pappasmurfsharem]

I bought some j201's from tayda and they look and act just like yours. Not trying to knock against tayda though, because in that same order I got some box caps and they're just fine. Just a heads up if anyone wants to buy some j201's from tayda. Luckily, I'm only out $2.50.

That's strange.

All my J201s from TAYDA look like the Fairchild on the right. Not to mention my BSIAB and Wampler Pinnacle clone sounds amazing.

[deadastronaut]

@gary:  everything in europe is expensive apart from beer?..., gord blimey luv a duck, me old china, fruit cake, plates of meat ,apples n pears, whistle n flute, dog n bone,  try England ...central London £4.50 gbp a pint of crap lager...

thats why i brew my own real ale... ...cheap and tastes 10 times as good. .


oh and petrol £1.42 a litre...not a gallon.

[garcho]

I forgot England isn't Europe! 

For the next contest, can we fund you to brew some DIYSBrew for the prize?

[haveyouseenhim]

If it ain't Murrica it might as well be one them dagum oriental countries.

Drink a real mans beer       steel reserve

[askwho69]

I bought some j201's from tayda and they look and act just like yours. Not trying to knock against tayda though, because in that same order I got some box caps and they're just fine. Just a heads up if anyone wants to buy some j201's from tayda. Luckily, I'm only out $2.50.

That's strange.

All my J201s from TAYDA look like the Fairchild on the right. Not to mention my BSIAB and Wampler Pinnacle clone sounds amazing.

Ohhh my GOSH! tayda has j201 but WHEN i measure the idss and the like... its very far from the real j201 i bought from other suppliers... the logo fairchild is different from tayda.. tayda has cheap logo on it rather than from my other supplier!!! TAYDA HAS FAKE J201!! but still worked though!! they measure as off



J201 Real FC            J201 Tayda          J201 FC       MPSA102   
IDSS - .36              IDSS - 1.6            .35                8.8
VP - .66                Vp - 1.56               .65                3.28
RS -  1522              Rs 809                1541              309
Rd - 18750              RD - 2857          17743             168
Vs - .25                .62                     .25                  1.8
Vd 5.75                 6.01                    5.37               7.22
Id .16                  .76                     .16                   5.84
Av 6.2                  1.8                     5.8                    .3
Av 15.8                 4.9                     15.2               -11.3
Vo 7.5                  5.1                     6.9                   1.6
Cp 104.6nf


       
5457 -04               jo8                      d3
5457                    tayda                j201
IDSS - .14             1.3                     .29
VP - .98               1.47                    .61
RS - 5851              939                     1746
RD - 44010             3642                    21662
VS -.38                .58                     .23
VD -5.98               5.95                    5.35
Id .06                 .62                     .13
Av 3.8                 1.9                     6.2
db -11.5               5.8                     15.9
vo - 6.8               5.3                     7
cp -27n                170n                   91.2n


All the tayda has high readings!!! its damn fake

[darron]

Oh wow... Interesting with tayda. Never ordered from them but respected company.

I have a box full of legit j201's isolated from my obvious knock off ones. They came from two of our very close favorite suppliers and I found some fake ones in there. Can't confirm who it came from though.

[J0K3RX]

I bought some j201's from tayda and they look and act just like yours. Not trying to knock against tayda though, because in that same order I got some box caps and they're just fine. Just a heads up if anyone wants to buy some j201's from tayda. Luckily, I'm only out $2.50.

That's strange.

All my J201s from TAYDA look like the Fairchild on the right. Not to mention my BSIAB and Wampler Pinnacle clone sounds amazing.

Ohhh my GOSH! tayda has j201 but WHEN i measure the idss and the like... its very far from the real j201 i bought from other suppliers... the logo fairchild is different from tayda.. tayda has cheap logo on it rather than from my other supplier!!! TAYDA HAS FAKE J201!! but still worked though!! they measure as off
     
All the tayda has high readings!!! its damn fake

Damn shame!!! Un-cool! Maybe start ordering SMD version of the J201 - MMBFJ201 / marking - 62P  still available last I checked Mouser
I know, I know... Run! Run for your lives... it's surface mount!!

http://www.mouser.com/ProductDetail/Fairchild-Semiconductor/MMBFJ201/?qs=sGAEpiMZZMv4z0HnGdrLjpo3FY8YkyPvx%252bQykc9k8ic%3d

[psychedelicfish]

I ordered some j201s from tayda, and they all look like the fake ones... I tested the VGS(off) and the IDSS using the tester on the Fetzer Valve page, and while all of them were within spec for VGS(off), only one of them didn't have too high of an  IDSS, and even then that one was right on the upper end of the spec.

[EATyourGuitar]

I got some fake AF128 in a super shiny metal can. I should have known by the name and picture. they just clone what sells. AC128 is selling for a high price so china invents AF128. notice how %90 of fake germaniums on ebay have the same fresh and shiny package with no oxidation like you would expect.

[darron]

 :icon_sad:Magnatec do some new af128, ac128. They aren't bad really. I wouldn't say that they are 'fake' since lots of companies made them. Lots of companies make 4558, 072 etc etc chips too.

I do get a bit annoyed when people sell the tungsram ac128 etc as vintage when they look a bit oxidizes and similar. Not shiny. Tell you what though, I'd take a shiney new magnatec one over the "T" tungsram ones around.

You're right, they label them to what they know people are looking for, but for our purposes they do a similar trick.

[EATyourGuitar]

The retailer had these af128 listed germanium NOS pnp but they were silicon with %33 working %33 not working and %33 overpriced diodes (broken transistor). That is not good business or good transistors IMO. What i mean about the oxidation is a good sign that they are actually old.

[darron]

i've had my share of shitty dealing with certain online sellers. been bitten too many times to not have bad memories stirred up. so, i have sympathy for people buying them

just saying too, if you lookup 'ac128' on ebay there's a lot of older/oxidised looking ones. doesn't mean they are actually vintage or better. with the "T" - tungsram. i've literally got hundreds of them in my collection of thousands of ge trannies. from around the 80's from memory? the chinese 128's can be a bit average. the uk 128's from magnatec were discontinued last year and mostly sounded really good after circuit adaption, so there's no need to disregard all newies. in every case you get bad eggs too so the guys on QA were not targeting audiophiles.

[rockhorst]

The retailer had these af128 listed germanium NOS pnp but they were silicon with %33 working %33 not working and %33 overpriced diodes (broken transistor). That is not good business or good transistors IMO. What i mean about the oxidation is a good sign that they are actually old.

It's really easy to oxidize stuff, harder to keep it shiny

[caress]

yup i'll also chime in here to say i got 2 different loads of the reject j201s from tayda.  one in an order i placed around december and another i just recently placed (which was much smaller, just testing to see if they still had the same ones).  they do work, but as i use j201s in 2 of my production pedals as gain stages i can objectively say that the biasing is a bit off and they have significantly less gain than a real j201.   

[R.G.]

Think about parts counterfeiting the next time you buckle your seat belt on an airplane.