2SK170BL

[sianturi]

Umut,
Just measure the the current Idss (current flowing between power supply and drain). Short the G-S (i.e. Vgs = 0V), and apply Vds = 10V (without any resistor). You should get between 6-12 mA. All my toshiba JFETs are well within this range.

 

[umut1001]

I finally found my multimeter and found the results
Its ma range is not working so i measured it by using 0,22ohm resistor
original japan ones have 2,3mv on resistors so it makes around 10,5ma
and thailand ones(maybe fake) They are around 2,8- 3,1mv so it makes more than 12ma

 

[umut1001]

I also measured gs resistance with precision lcr meter
original one have 1Mohm resistance @ 1khz
118kOhm @10khz
and 20kOhm @100khz
fake one
10kOhm @ 1khz
11kOhm @10khz
13kOhm Q 100khz

 

[umut1001]

I also found 15ma ones.

 

[AndrewT]

That makes them V grade, not BL.

 

[umut1001]

That makes them V grade, not BL.

I also have genuine japan made V grade 2sk170 and its Gate to source resistance @1kHz also measures 1Mohm.Thailand made ones 10kOhm measurements makes them "fake grade" not V grade

 

[WalterW]

😀😀🙂

 

[Salas]

I finally found my multimeter and found the results
Its ma range is not working so i measured it by using 0,22ohm resistor
original japan ones have 2,3mv on resistors so it makes around 10,5ma
and thailand ones(maybe fake) They are around 2,8- 3,1mv so it makes more than 12ma

Check the mA range fuse inside your meter. Probably blown.

 

[umut1001]

Check the mA range fuse inside your meter. Probably blown.

Thank you .I had fixed it.Fake ones IDSS are between 14-15ma all.

 

[Salas]

If printed BL and measure 14-15mA there is no question, they are fake. Install high rapture capacity ceramic fuses if you ever use the meter on wall box building power. For safety.

 

[Salas]

Always look for "one" in genuine Toshiba 170 to be printed like l and for "seven" to have little curved leg. Thin gray-brownish etched print. Never have a letter in the back circle. Shallow small circle. Have a short _ scar on top middle where the face meets the back. Shiny legs and not totally flat. 14mm. Little copper showing where they enter the body sometimes.

 

[umut1001]

Always look for "one" in genuine Toshiba 170 to be printed like l and for "seven" to have little curved leg. Thin gray-brownish etched print. Never have a letter in the back circle. Shallow small circle. Have a short _ scar on top middle where the face meets the back. Shiny legs and not totally flat. 14mm. Little copper showing where they enter the body sometimes.

very good description