Transistor Substitutions

[darrenw6000]

What are the most important numbers when finding substitutes, so many considerations, hfe, mhz etc etc

[madbean]

That really depends on the type of transistor you are trying to sub for and what it is doing in that particular instance. Honestly, when I find myself in this situation where I don't already know I just Google (transistor name) and "sub" and many times that gives good info. Sometimes from DIYSB, in fact.

Even some transistors with very close specs don't work as subs but that is more rare, IME. For instance, the VFE Pale Horse I've been building calls for a 2N5484 or J113. Well, I had a J112 that was very close to the 113 specs for certain traits but it just did not work for that particular application.

At the most basic, stuff like Hfe, NPN vs PNP etc for BJT transistors; Vgs and Idss for JFET. And pinout is always a consideration esp. with JFET because they can get weird.

[lego4040]

Thanks for the tip Brian. By the time I get to finding a substitute that I might have at hand usually  I can find what I need on the net and order it