new source of J201 transistors?

[Sensei Tim]

I was on the mouser website getting ready to order some more surface mount J201 jfets when i found this:

http://ca.mouser.com/ProductDetail/InterFET/J201/?qs=sGAEpiMZZMvplms98TlKY8skfZQpQP4sTauuqV%252bhBdb8eh7Ae4NdvQ%3d%3d

a bit on the pricey side, though

and the datasheet:
http://www.interfet.com/datasheet/J201/

[Frank_NH]

Well, if you order 100 at ~$2 a FET, probably not too bad.  I suppose we could arrange a group buy for JFET junkies like us ...

[rocket88]

i'ld be up for it, but smallbear still has j201's for $0.55 each, so not sure why we would spend nearly 4x the amount.

[motterpaul]

I double-checked my last batch (just about two months ago) and I thought I had paid $.50 apiece, but it was closer to $.17 apiece.

Here they are for $.15 apiece (15-cents) - pictures shows Fairchild:

http://www.ebay.com/itm/10pcs-J201-FAIRCHILD-Transistor-TO-92-/252033690244?hash=item3aae60ea84

Lately I have been looking at Smallbear and Mouser and I see a lot of outrageous prices. Fine if you only want one piece, I guess, but....

[Beaker]

Paul, I would be VERY suspicious of those, they look like fakes to me.

[motterpaul]

I read that you just had am incident with fakes, but I got my last batch of J201s here:

http://www.ebay.com/itm/50pcs-J201-FAIRCHILD-Transistor-TO-92-/261611171059?
and they all looked & tested good.

I did get some 5457s that look different from the Fairchilds, but they also still worked pretty much the same (though I have not tested all of them).

Anyway - at 30-cents apiece vs $3.00, I'll take a chance.

[motterpaul]

You are right that the picture looks suspect, I will say that in real life they look identical to the ones I already had - except for one which had a big F - that one is the last one I tested below.

Since I was running out when I bought the last batch I would guess that most of the ones I just tested were from the new batch.  I will say they have always worked for me.

according to Geofex (who tested 75 5485s) it is not unusual for specs to run "all over the place" in a given batch.

Anyway - it's up to each person, but these worked for me and at 1/10th the price. YMMV

Test Result:
N-Ch JFET
Blue-G, Symmetrical Src/Drn
Vgs(off)=-0.79V at Id=5.0µA
Vgs(on)=0.36V at Id=1.27mA
gfs=1.8mA/V at Id=0.8mA to 1.3mA
Idss=0.64mA at Vds=2.99V

Test Result:
N-Ch JFET
Blue-G, Symmetrical Src/Drn
Vgs(off)=-1.15V at Id=4.8µA
Vgs(on)=0.28V at Id=1.75mA
gfs=2.1mA/V at Id=1.1mA to 1.8mA
Idss=1.16mA at Vds=3.00V

Test Result:
N-Ch JFET
Green-G, Symmetrical Src/Drn
Vgs(off)=-1.21V at Id=5.0µA
Vgs(on)=0.26V at Id=1.88mA
gfs=2.2mA/V at Id=1.1mA to 1.9mA
Idss=1.30mA at Vds=3.01V

Test Result:
N-Ch JFET
Red-G, Symmetrical Src/Drn
Vgs(off)=-1.29V at Id=5.1µA
Vgs(on)=0.25V at Id=2.00mA
gfs=2.2mA/V at Id=1.2mA to 2.0mA
Idss=1.43mA at Vds=3.01V

Test Result:
N-Ch JFET
Green-G, Symmetrical Src/Drn
Vgs(off)=-1.09V at Id=5.0µA
Vgs(on)=0.29V at Id=1.73mA
gfs=2.1mA/V at Id=1.0mA to 1.7mA
Idss=1.11mA at Vds=3.00V

Test Result:
N-Ch JFET
Blue-G, Symmetrical Src/Drn
Vgs(off)=-1.12V at Id=5.1µA
Vgs(on)=0.28V at Id=1.70mA
gfs=2.0mA/V at Id=1.0mA to 1.7mA
Idss=1.11mA at Vds=3.00V

Test Result:
N-Ch JFET
Blue-G, Symmetrical Src/Drn
Vgs(off)=-0.58V at Id=5.3µA
Vgs(on)=0.38V at Id=0.99mA
gfs=1.7mA/V at Id=0.6mA to 1.0mA

Test Result:
N-Ch JFET
Green-G, Symmetrical Src/Drn
Vgs(off)=-1.29V at Id=4.9µA
Vgs(on)=0.25V at Id=1.93mA
gfs=2.0mA/V at Id=1.2mA to 1.9mA

Test Result:
N-Ch JFET
Green-G, Symmetrical Src/Drn
Vgs(off)=-0.75V at Id=5.0µA
Vgs(on)=0.33V at Id=2.01mA
gfs=3.2mA/V at Id=1.2mA to 2.0mA
Idss=0.99mA at Vds=3.01V

Test Result:
N-Ch JFET
Red-G, Symmetrical Src/Drn
Vgs(off)=-1.02V at Id=4.8µA
Vgs(on)=0.29V at Id=1.49mA
gfs=1.9mA/V at Id=0.9mA to 1.5mA
Idss=0.92mA at Vds=3.01V

Test Result:
N-Ch JFET
Green-G, Symmetrical Src/Drn
Vgs(off)=-0.79V at Id=4.9µA
Vgs(on)=0.36V at Id=1.27mA
gfs=1.8mA/V at Id=0.8mA to 1.3mA
Idss=0.64mA at Vds=2.99V

They all look pretty close except for VGS(off) - I see some specs are missing ID=dss, but I found that if I tested them again it usually came up.

[Muadzin]

I ordered some J201's from Polida in the past that I used in some Wampler builds. A Pinnacle, Plexi Drive and a Black 65 I built yesterday. Using a JFET matcher board from Madbean I found several matches for each build. The Pinnacle I found to be underwhelming, which I thought was weird as everybody kept saying it was a hi-gain pedal. The Plexi Drive was low gain, but that seemed to be in character. But when I fired up the Black 65 with a matched set there was no gain at all whatsoever. By now I had some SMD J201's with adapter boards and swapped them in and lo and behold, there was gain! So I took a good look at the Polida J201's and what do you know? Fakes! Normally the lettering is sort of kinda engraved into transistors but in these cases it looked more like it was sanded off and the new labels stencilled onto it.

Having finally learned that my J201's were fakes I took a look at my Plexi Drive and Pinnacle builds again. Previously they had me underwhelmed so I swapped the transistors for the SMD J201's. The Plexi Drive is still a low gain drive. But now with ten times the amount of gain. And the Pinnacle has now become a hi-gain beast!

I learned my lesson. F*** you Polida! Chinese sellers suck! Don't these morons understand that these kind of practices are bad for their long term business? Never EVER order any semi conductors from China again!!

[Silver Blues]

Well I wouldn't go that far, just because one seller is turning out fakes doesn't mean they all are. China is kind of a big source of parts for this hobby. I understand your anger however, this is not something that should happen. Perhaps you should report this to eBay buyer protection and see if you can't have them do something about it. They are usually not particularly tolerant to sellers that break their rules.

[rocket88]

i completely agree with silver. it's really sad, because i had ordered a lot of IC's from polida, and they were all good. that was 2yrs ago maybe, and now there's a lot of people getting bad and/or fake parts from them. report it to eBay right away, and you'll get a refund. don't even contact polida other then if you want to inform them that you're filing a complaint for fake components.

there are many good chinese sellers on ebay, but the sad fact is that there's a lot of occurrences where people have found out that there are companies that will use more then 1 ebay name for selling. what makes this really interesting is that one may have a bad reputation and the other a good reputation, when they sell the exact same parts.

on another note, i've had a rather large IC order in my eBay cart from polida, i'm pretty happy i didn't complete the order, since this is like the 5th time i've heard of bad business practices from them.

[Muadzin]

I bought those J201's more then a year ago. Can you even still get your money back after all that time?
Right now I'm more angry at myself then at them. The golden rule is still, when something is too good to be true, it usually is. When they offer it way, WAY cheaper then a reliable internet store like Smallbear it's probably better to assume its too good to be true.

This whole thing makes me glad though that I had just placed a new order with chromosphere for more mmbfj201's and adapter boards. Now that I have some good J201's in my builds they start to sound amazing!

[rocket88]

muadzin, what you have to remember is that when you order from china that's the same place companies like smallbear get their parts from, and by ordering from some of these chinese companies you're basically going right to the distributor. for instance, from tayda we usually pay about $5-6usd for an enclosure, 125b or 1590b, from tayda. i've gotten in contract with who they by from, and i'm paying about $2-3usd for an enclosure, 125b or 1590b. they are in china, and $3.40usd for 1590dd. so you really can get things drastically cheaper then we normally find from our typical retailers, but i have to by 20 enclosures at a time.

when you order from companies in china on eBay, you just have to be careful of their rating, and read to see if people had issues with them. i'm going to be ordering a massive amounts of IC's from ele-parts, rating of 99.8%. i've ordered from them before and everything was perfect. again prices are very cheap, but they are reliable, and you have look at the pictures carefully. i've don't a lot of research on identifying  counterfeit IC's, and in most pictures you can tell if something looks off. plus as soon as i get them i check them in a circuit i know will work, if it doesn't or has issues i contact the seller and file a complaint so others font get counterfeit parts. i also will do the acetone test with them if they're modern IC's.

[Sensei Tim]

rocket88 wrote

 i've gotten in contract with who they by from, and i'm paying about $2-3usd for an enclosure, 125b or 1590b. they are in china, and $3.40usd for 1590dd. so you really can get things drastically cheaper then we normally find from our typical retailers, but i have to by 20 enclosures at a time.

care to share with the rest of the class? ;)

[Muadzin]

rocket88 wrote

muadzin, what you have to remember is that when you order from china that's the same place companies like smallbear get their parts from, and by ordering from some of these chinese companies you're basically going right to the distributor. for instance, from tayda we usually pay about $5-6usd for an enclosure, 125b or 1590b, from tayda. i've gotten in contract with who they by from, and i'm paying about $2-3usd for an enclosure, 125b or 1590b. they are in china, and $3.40usd for 1590dd. so you really can get things drastically cheaper then we normally find from our typical retailers, but i have to by 20 enclosures at a time.

when you order from companies in china on eBay, you just have to be careful of their rating, and read to see if people had issues with them. i'm going to be ordering a massive amounts of IC's from ele-parts, rating of 99.8%. i've ordered from them before and everything was perfect. again prices are very cheap, but they are reliable, and you have look at the pictures carefully. i've don't a lot of research on identifying  counterfeit IC's, and in most pictures you can tell if something looks off. plus as soon as i get them i check them in a circuit i know will work, if it doesn't or has issues i contact the seller and file a complaint so others font get counterfeit parts. i also will do the acetone test with them if they're modern IC's.

Oh, I get that. Kinda hard to fake a 125b though. I'm fine with ordering parts that are in current production from China. That's why I said don't order rare semi conductors from China. When it comes to such parts I'd rather spend some extra money for a reliable vendor then take my chances with some Chinese, whose parts for mysterious reasons seemingly have to travel by ox cart via the Silk Road as they take forever to arrive, and then I have to put them through all sorts of hoops to see if they're legit? Life's too short for that. When I order parts I want them to arrive ASAP and I want to use them in my builds knowing they're reliable. I don't think that's too much to ask for, right?

[rocket88]

nah bro. i'm not coming at you as if you're saying anything wrong, just point out how a lot of this works. it's not that you can get a fake 125b, just that technically if it's not made by hammond it's a clone, and there are good and bad ones out there. how about this, $0.09 each for aluminum knobs that usually go for $1.00 each.

it's just that you have to remember that anyone that has a company that sells, they have a distributor that they buy from, they raise the price to sell to us. it's just retail.

and, you're correct about "rare" parts. if it's too cheap walk away.