JFET with configuration SDG (source , drain , Gate)

[haseeb zaib]

hello everyone

I have this transistor in TO-92 package. Now the number on it is all gone, I checked it using transistor tester it came out to be a jfet with configuration of SDG. I have attached a picture of transistor tester. Now I cant find jfet similar with this configuration. So does anyone here knows about any jfet with this configuration? please tell me if you know about any.

[moffy]

Sorry, but it looks like a straight forward NJFET, the tester is just using a slightly different symbol to what most are used to(the diode is normally drawn in the gate rather than the source).

[Kleinstein]

With nearly all JFETs drain and source are interchangable. At least the transistor tester will have a very hard time to tell them apart. So for the pinout the main point is finding one with the gate on the right side.  An example would be J111-J113 or  J201/J202.  For a replacement one can turn TO92 parts the other way around with no big problem.

[haseeb zaib]

  For a replacement one can turn TO92 parts the other way around with no big problem.

This is exactly what I am saying to my senior engineer but he want everything same XD

[Kleinstein]

There are JFETS in To92 case with the gate on all three pins, though some may be hard to get by now:
BF245 , BF256 : gate on the left
SK117,SK170  : gate in the middle
J111 etc.         : gate on the right

Finally there is a really odd one from Motorola (but I think this is more like a typo):

[BrokenYugo]

  For a replacement one can turn TO92 parts the other way around with no big problem.

This is exactly what I am saying to my senior engineer but he want everything same XD

Many JFET data sheets note that drain and source are interchangeable, if that's what they're worried about.

[mag_therm]

2N4416   123 : SDG  To72
It has a 4th pin on the circle connected to the case