Replacement For Toshiba 2SK170/2SJ74

[Zen Mod]

for start ...... to replace 2SK/2SJ - you need 2SK/2SJ

🙂

 

[uchu007]

Okay ,
zenmod i understand this is not 2 complementary pair

 

[meanie]

I have a batch of J74/K170 Jfets, initial testing with 10v supply shows IDSS= 3~5 mA range.
Are they good for any Pass amp here ?

Thanks

 

[NicMac]

If they are BL-grade, they are almost certainly fakes and not recommended for use in Papa amps😉

 

[Skylar88]

It may be GR grade, according to the datasheet.

IDSS classification:
GR: 2.6~6.5 mA
BL: 6.0~12 mA
V: 10~20 mA

 

[NicMac]

The grade is indicated on the FET so no guesswork needed here.
Last year I did actually buy a couple of J74 GR-grade from what I thought was a reputable company (Reichelt), but as suspected they turned out to be fakes (way to low transconductance). They are still selling them (link).

 

[carsten.witt]

Yes Reichelt has only fakes and I know many people that send measurements to R and they didn't react :-(

 

[darrr]

Does anyone have experience with shopping in utsource?

 

[TonyTecson]

Does anyone have experience with shopping in utsource?

bad experience, i ordered IXYS depletion mosfets from them, IXYS parts did arrive, but they were enhancement mosfets, what it funny is that the markings are correct....
i even ordered from another source in china, same thing....

 

[quyda]

If they are BL-grade, they are almost certainly fakes and not recommended for use in Papa amps😉

Hi,
I'm about to purchase from this guy for my FW F5 project, are you telling me that they are likely fake too?
Anywhere reputable I can buy from, preferably Toshiba's

 

[NicMac]

From who are you about to purchase?

 

[Skylar88]

Hi,
I'm about to purchase from this guy for my FW F5 project, are you telling me that they are likely fake too?
Anywhere reputable I can buy from, preferably Toshiba's

Not Toshiba's, but Linear Systems from the DIYAUDIO STORE should be fine too.

Otherwise get Toshiba's from Spencer in Singapore.

 

[bloozestringer]

I ordered a matched quad for another project from Boozhound.

 

[quyda]

From who are you about to purchase?

Sorry, forgot to include ebay link

 

[6L6]

Punkydawgs is 100% genuine parts.

 

[Stixx]

Punkydawgs is 100% genuine parts.

^^^^^^^^^^^^^^ ^^^^confirmed.

 

[quyda]

Punkydawgs is 100% genuine parts.

Glad to know! What's the difference between BL and GR btw?
And do you know why
Toshiba 2SJ74 + 2SK170 LAB MATCHED OCTET to 0.03mA / 4mV (10mA range)
is CHEAPER than
Toshiba 2SJ74 + 2SK170 LAB MATCHED OCTET to 0.03mA / 4mV (7-8mA range)

 

[Dennis Hui]

That's Idss grading. GR: 2.6mA ~ 6.6 mA. BL: 6mA ~ 12mA.

There's probably more request for 7 to 8 mA parts from buyers.

 

[kstagger]

Ditto: When I redid one of my Aleph J boards, I used 2SJ74s from punkydawgs - can confirm they are the real deal.

 

[meanie]

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

The J74 were too low to be listed in the BL grade, most likely fakes.
But the K170BL tested fine.... Here are the 50pcs samples, will probably order more of these. A few pair is almost perfect IDSS match !

Korg triode B1, here i come ...yeah !