Central Semi 2N3819 back in spec?

[OneRoomStudio]

I've heard lots of stories about various 2N3819's bought over the years having Idss measurements of 12-20mA, which make them difficult/impossible to bias up correctly in a U87 circuit. Technically, those are "in spec" since the data sheet specifies 2-20mA for Idss, but vintage 2N3819's were usually in the 2-4mA range.

All of the Central Semi ones I've bought from Mouser recently have been back within the "vintage" specs though. I just measured 25 of them, and they were all between 2.2 and 3.1mA. Pretty tight tolerance for JFETs! They may have figured out the process to build them 'like they used to.'

Anyway, just wanted to share my experience. I have been buying these: https://www.mouser.com/ProductDetai...r/2N3819-PBFREE?qs=OlC7AqGiEDla/gXW0b%2BF8A==

 

[McIrish]

That's good to know. The ones I bought a couple years ago were worthless. I didn't end up using them at all and moved to a different FET.

 

[OneRoomStudio]

No guarantees of course, I might have just gotten a good batch, but worth checking out...

 

[RuudNL]

The Central Semiconductor 2N3819 FETs I have ordered in the past were all over the place...
Sometimes I've got a 'good' batch, but most of the time specifications varied wildly.

 

[Migs 31]

The Central Semiconductor 2N3819 FETs I have ordered in the past were all over the place...
Sometimes I've got a 'good' batch, but most of the time specifications varied wildly.

Maybe try Fairchild ones.
Might be more consistent for Microphone use ?
M

 

[RuudNL]

Where do you get original Fairchid 2N3819 FETs nowadays?
(Fake Fairchild 2N3819 you can get at AliExpress! )

 

[Migs 31]

Where do you get original Fairchid 2N3819 FETs nowadays?
(Fake Fairchild 2N3819 you can get at AliExpress! )

NOS, over the counter in small shops around here.
Where an old grumpy man sternly warns you not to use such & such parts/values etc.

M

 

[RuudNL]

That reminds me of a shop in Hilversum (near the place were I lived) where young uninterested guys behind the counter advised me not to use a certain part, but use THIS part instead.
In those cases I used to say: "just give me what I asked for!".
(At the time I had been working with electronics for over fourty years, so I knew what I was doing.
The boys behind the counter had just gotten out of diapers... )
No wonder this business went bankrupt!

 

[cyrano]

NOS, over the counter in small shops around here.
Where an old grumpy man sternly warns you not to use such & such parts/values etc.

M

I used to drive that old man to madness with my questions...

You're lucky to still have those shops around. Nearly all vanished here.

 

[maurizionatoli]

That reminds me of a shop in Hilversum (near the place were I lived) where young uninterested guys behind the counter advised me not to use a certain part, but use THIS part instead.
In those cases I used to say: "just give me what I asked for!".
(At the time I had been working with electronics for over fourty years, so I knew what I was doing.
The boys behind the counter had just gotten out of diapers... )
No wonder this business went bankrupt!

That reminds me of a shop in Hilversum (near the place were I lived) where young uninterested guys behind the counter advised me not to use a certain part, but use THIS part instead.
In those cases I used to say: "just give me what I asked for!".
(At the time I had been working with electronics for over fourty years, so I knew what I was doing.
The boys behind the counter had just gotten out of diapers... )
No wonder this business went bankrupt!

there was an electronic components shop near me where the owner, to every request, invariably replied: "what should you do with it?" because he never had what you wanted and he wanted to convince you to take something that he had instead, only much more expensive and always useless. I once asked him about "metal film" resistors and he replied: "they don't exist, maybe you want the metal layer ones" (in English the pun doesn't make sense, in Italian that type of resistor can invariably be called "metal layer" or "metallic film" are synonymous. Then he added: "I don't have any anyway". It was the last time I set foot in that shop, it's still open and sells very low quality Chinese stuff...

 

[Cqwet Dbdfte]

Can you use the 2N3819 SOT-23 version?