In the old days we used to have test equipment that you could stick a transistor in and it would show you the characteristics of the device.
I doubt any still exist, so I would suggest you set up a simple amplifier circuit, one for NPN and one for PNP and plug them in a low voltage test rig to see which one works.
From there you can adjust the amplifier gain and current drive capabilities.
If you have an application for them, use the test rig to see if they would work, then go from their.
It is probably not worth investing a whole lot of time as you can buy these things for pennies.
In the old days we used to have test equipment that you could stick a transistor in and it would show you the characteristics of the device.
I doubt any still exist, so I would suggest you set up a simple amplifier circuit, one for NPN and one for PNP and plug them in a low voltage test rig to see which one works.
From there you can adjust the amplifier gain and current drive capabilities.
If you have an application for them, use the test rig to see if they would work, then go from their.
It is probably not worth investing a whole lot of time as you can buy these things for pennies.
There should still be multi-meters available that have the ability to do checks and get Beta for them. I know my Craftsman meter does and it's about 13+ years old. But DAB is right, I remember using a transistor "checkers" a few years ago. Jerri Ellesworth shows one in one of her videos when she creates a cat's wisker based transistor.
