My Transistors, original or copy?

Jump to Latest
W

WalterW

Member
Joined 2012
Paid Member
Oh, no bought fakes again.... 2SK170BL
First I ordered 10 pieces, they were the real stuff, so I bought another 100.....fakes.

Good fakes though, laserprinted, Yfs = 18 -19 mS, V ( pinch off) = -0.85V instead of max. -0.5V.
See picture... good one, fake one...
 

Attachments

  • fake.jpg
    fake.jpg
    601.7 KB · Views: 405
K

kees52

Member
Joined 2009
WalterW said:
Oh, no bought fakes again.... 2SK170BL
First I ordered 10 pieces, they were the real stuff, so I bought another 100.....fakes.

Good fakes though, laserprinted, Yfs = 18 -19 mS, V ( pinch off) = -0.85V instead of max. -0.5V.
See picture... good one, fake one...
Click to expand...

Dat sucks vriend.

Ik heb igbt,s binnen, 60 amps voor een las inverter.

I have igbt,s received, 60 amps for weld inverter, I do not now she real, but I have not yet problems with it .

Do not understand people do rip off because she drain the store intto the river.

Niet meer dan 10 kopen he, beter 10 leveranciers if you get my drift.

regards

kees
 
A

AndrewT

R.I.P.
Joined 2004
WalterW said:
Oh, no bought fakes again.... 2SK170BL
First I ordered 10 pieces, they were the real stuff, so I bought another 100.....fakes.

Good fakes though, laserprinted, Yfs = 18 -19 mS, V ( pinch off) = -0.85V instead of max. -0.5V.
See picture... good one, fake one...
Click to expand...
V pinch off varies with Idss.
A low Idss BL will have a low Vpinchoff.
A high Idss BL will have a high Vpinchoff.
Since BL varies from 6mA to 12mA (2:1) expect a similar range of Vpinchoff.
the 2sk170 datasheet shows typical Vgs off (0.1uA) of 700mV for 12mA Idss dropping to 550mV for 6mA Idss.
These being typical will have a tolerance.
I would expect at least 500mV to 750mV for the BL grade, but I have not measured many Vgs off, so I don't have reliable data.
But clearly your 500mVgsoff for a guide value for the BL grade is misleading.
 
Soundhappy

Soundhappy

Member
Joined 2012
WalterW said:
I will first give the shop a chance to solve it (widerrufen), before I name and shame them ;)
It's a German shop who probably isn't aware they are fakes....
Click to expand...

Yeah WalterW you have reason let's make life constructive
hope people learn from this lesson and bring us good semi's
after higher quality controls in near future :) Greetings
ps. LSK jfets from DiyAudio store was like usual safe deal
 

Attachments

  • E217B257-9D13-4583-B4C8-35E93031F34D.JPG
    E217B257-9D13-4583-B4C8-35E93031F34D.JPG
    162.3 KB · Views: 309
K

Keepsake10

Member
Joined 2009
Hi soundhappy,
The 8 watt Le Monstre looks quite interesting. I build until now some tube amplifiers, nevertheless I am not an "extremist" so transistors are an option as well. Actually I have some old fullrange speakers saved from Nordmende exquisite de luxe - one of the biggest and latest tube device made at Nordmende. This Nordmende had a tube amplifier with ell80 rated at about 8,5W per channel. Anyway, those speakers are really impresive - oval construction (about 33 cm / 24 cm) and might be an excellent candidate for Hiraga Le Monstre.
Is out there any safe source for the original transistors ?? at least all Jfets I could find on WWW looks like fakes.
 
K

kees52

Member
Joined 2009
wg_ski said:
There isn't any "MJ150024". It's only supposed to have one zero. One is marked with a different number and that doesn't correspond to any known MJ, even if you take out the extra zero.
Click to expand...

Oke thanks for clarity. I did search fir you but I think these are special made, as this company do work for army.

this sucks you have to measure, what is difficult I think to find out amps and voltage.

I did use the mje 15024 for audio did well.

regards

kees
 
Last edited:
You must log in or register to reply here.
Top Bottom