ft tester

[ppppenguin]

hfe (current gain) is often misunderstood. Good circuit design should never rely on hfe, except that it must be high enough that there isn't too much base bias current. Of course not all design is good. There may also be exceptions for germanium devices where hfe was often very low. I've also had problems with line output transistors such as BU208 which can have incredibly low hfe and thus need a lot of base drive to get them to saturate.