2SK30 that are not real 2SK30?

[Gilles C]

I tested a switchbox with the 2SK30AY that I bought yesterday.

It was not working... the pinout is SDG, not SGD as with the original 2SK30s.  :evil:

So I had to twist the pins to make them fit in the pcb that was made for 2SK30s.

So I was wondering. Did someone else got any 2SK30s with that SDG pinout?

I could not find any specs sheets with that pinout with the 2SK30.

I beging to think they don't make them anymore and just stamp 2SK30 on them to make them look like 2SK30s...

Btw, one of them didn't like being unsoldered and resoldered... So I fitted a J113 to replace it to do a few tests.  :twisted:

Gilles

[R.G.]

It is entirely possible that you got counterfeit devices. There is an ongoing underground counterfeiting high tech stuff. Read more at Rod Elliot's Elliot Sound Products in the articles.

Sadly, this even extends to things like counterfeit high-strength bolts. Think about that the next time you get into a car, train, elevator, or airplane.

Frankly, I'm surprised that no one has counterfeited germanium devices like the NKT275. Maybe the small market protects us.

[Gilles C]

It is entirely possible that you got counterfeit devices. There is an ongoing underground counterfeiting high tech stuff. Read more at Rod Elliot's Elliot Sound Products in the articles.

I didn't remember that article. Thanks.

From what I read, there need to have a logo that says what company made them I think. Or it must be a part number used by only one company.

I don't think there is a company logo, so it could just be a cheap copy. Just like the voltage regulators I once bought with very flexible legs.

I want to make a test jig to test some of the specs of these FETs, like the ON resistance, to see if it is close enough to be a 2SK30 with a different pinout, or a different FET...

I am still waiting for some more 2SK30s I order from Electronix. I wonder if those will be ok.  :?:  :?:  :?:

Gilles


Added: I found a few companies other than Toshiba and Hitashi that make 2SK30s

http://www.americanmicrosemi.com/

Wonder about the price???
http://store.americanmicrosemiconductor.com/2sk30a.html

That's from this page

http://www.searchdatasheets.com/search.php?q=2SK30a&t=

[mikeb]

AFAIK, the counterfeiting only occurs with more expensive items. You'd have to produce a hell of a lot of counterfeit small-signal active components (worh a few cents each) to make it worthwhile, whereas the high-powered (and hence much more expensive) active components offer a much tastier target. I'd be guessing that the pinout is simply different ... but would like to know if I'm wrong!

Mike

[phillip]

Frankly, I'm surprised that no one has counterfeited germanium devices like the NKT275. Maybe the small market protects us.

Actually...

There are a couple of sellers on eBay peddaling transistors that they call "NKT275" but they're actually just new production generic Germanium transistors.  One production run may be marked "NKT275" and the next production run may be marked "AC128."

Sad thing is...the guys sell that new production junk for as much as real ones would go for, mainly because they market them as  "genuine NOS!"

Sad goings on

Phillip

[Vsat]

I ordered 2SK30A-Y from Supremetronic in Toronto a few years ago. Last time I checked the stock list, it was still there, but you should inquire by email since the website is being changed and not all of the catalog is currently online. These had the standard pinout and proved to be pretty closely matched, Vgs(off) = 1.5V+/-0.1 volt when I tested 25 of them. I believe the transistor is still in production as the 2SK30ATM-Y...

[Gilles C]

I checked on their site before I ordered from Electronix, but as I didn't find anything on their new website, I decided to order from Electronix in place of sending Supremetronics an email.

Maybe I should have. I'll see.

I wanted some fast, so I also bought some locally, and these are the ones with the wrong pinout.

I will use them anyway, but I really want some with the correct pinout so I can test some layouts with that pinout.

I have only one week left before I go to a training out of town for 5 weeks (Montreal), so ordering some more right wouldn't be  a good move.

Gilles

[eaze]

Hi.
I wondered at this confusion.
Cause I'm a Japanese and have familiarity in a Japanese products (ex..semiconductors)
I've found schematics from US, "Ahh, is 2N5088 substitute 2SC945?" :cry:
...Always asking Google and found PDF of datasheets.

The following is small preparations and you'll not need to repeat.
Check it out, make a note, and you'll find good substitute

Well,,, in Japan, "2SK30A" is a most common and very popular.
for low-frequency use, especially audio-use.
And of cource, not VINTAGE/NOS, and not so expensive.

http://www.semicon.toshiba.co.jp/eng/
Click on datasheet search, You can find datasheet of TOSHIBA.

Its current part-number is 2SK30ATM. perfect substitute of "2SK30A"
TOSHIBA only carried out the minor change.
There is 2SK30ATM in a market actually.

AMS is just a seller, not a manufacture company.

=====
http://www.sm.rim.or.jp/~konton/Museum-7.htm
The minor change of "30A"was carried out in this way.
You'll notice the versions since 1970s.

Tons of data lists of Japanese transistor/FET also containing old things.
http://lobs.hp.infoseek.co.jp/data/data.html
The upper is bipolars, lower is FETs.

=====
2SK is J-FET or MOS-FET.
the digits following "2SK"shows original part-number for every manufucture.

=====
Japanese(or OEM) Bipolar-transisiter...
2SA PNP generally high-freq use, low-freq OK
2SB PNP low-freq
2SC NPN generally high-freq use, low-freq OK
2SD NPN low-freq

=====
In the case of TOSHIBA,
The alphabet added to the end expresses an Idss ranking.
You can specify it certainly.

See PDF of 2SK30ATM...

R: 0.30-0.75,
O: 0.60-1.40,
Y: 1.20-3.00,
GR: 2.60-6.50 [mA]

...Have you noticed that it is initials of a row like color-code?

2SK30A-O or -Y was often used by BOSS in 1970-80s.


In Bipolar,
that alphbet expresses hFE ranking.

[Gilles C]

Hey, Thanks a lot for the help and info.

About the code letters, it looks like colors indeed ... GR for GRey, etc...

But I never saw any other specs sheet other that the one for Toshiba and that was for the 2SK30ATM.

I'll check your infos a bit more later tonight.

I checked the 2 different 2SK30s I have and the one with the correct pin-out has the letters "ma" after the 2SK30A number.

The ones with the incorrect pin-out has a "68".

Must be to identify the company.

Gilles

[eaze]

hi, again.  

I think that you may mistake about pinout problem.

but I don't know your concrete application.

for example, switch-use J-FET,
It is satisfactory even if it replaces D and S.

In others,
It may mistake because of blurred printing.
3 & 8, B & R....

These are common mistake.
Although I do not suspect you :?

P.S.
GR must be GReen. so, BL is BLue...
for example >>>2SC1815-BL

[Gilles C]

GReen... Arg... that's right.  :oops:

Grey is "Slate" in the technical english language for the wires colors. I forgot. My main language is french, so...

The pinout problem is not with the SD being reversed. It's with the Gate being on one side (DSG) in place of being in the middle (DGS).

So I can't use the standard configuration (DGS) for the layouts. Or I can't use the wrong DSG configuration to repair a Boss effect that uses the standard DGS configuration.

Here is the layout I used for my test:

http://ampage.org/hammer/files/DUALLOOP.png

It uses the standard DGS configuration.

Hummm, just for fun, I'll post a picture of my two 2SF30 FETs.

Btw, I did a few tests with both a J113 and a 2SK30A FET, and they give me the same results. Well, at least as a switch. I still have to try them as audio preamps.

Thanks again

Gilles

Added: That reminded me of when I started working for an intercom company many years ago. They made a mistake when they started to use the following color code http://www.cisco.com/univercd/cc/td/doc/product/core/7204/7204ig/wire4icg.htm#38766

They inverted the solid color and the stripe color when they made all the cables and connections. So we had a new standard...

[Lonestarjohnny]

Thank's Ease, Very good site's with lot's of good info, and thank you to Gilles, very good code chart, i'll be useing these when i'm in need of a data sheet or code chart,
Johnny

[Gilles C]

 My pleasure. I like to give and get all the info I can get about anything...  

Mark Hammer is my hero...  

And it is true.

I don't have his memory or his knowledge, but I like to share anyway.

And thanks Ease for sharing your knowledge.  

Gilles

[eaze]

I agree with you, Gilles
I also have the same comment about info.

And, thank you for your detailed report!