Need help with Transistors

[Scubaru]

So, I have been playin around with electronics for a few years. Nothing more than some basic circuits with various gates, resistors, capacitors, etc. I finally started to study Transistors and kinda am looking for like a full overview or at least answer some questions I have.

Well I understand (or at least I think I do) that a NPN is open until power is applied to the "Base" which then allows power to pass between the "Collector" and "Emitter". The PNP works in the opposite, correct?

Now I had built a basic circuit once as a kid with one of those Radioshack kits and I remember taking the power off of the "Base" and the LED stayed on. However I have seen several videos on Youtube and from what I am seeing the Transistor acts like a switch, in that when power is removed, all power stops moving through the transistor, correct?

Now I wanted to go to Jameco.com and order some generic use transistors for circuits that carry between 5v and 12v. Is there a such thing as "Generic"? I just want something I can play with and get a feel for what capabilities I have with a few transistors.

Any other information you guys can give me would be great. I feel like I have a small grasp on this huge world of Transistors.....Thanks Guys!

 

[harps]

YouTube - MAKE presents: The Transistor]

hello

this guy explains transistors and other components in a series of youtube vids.: )

he explains npn pnp etc... its just not fast information ...make a cuppa tea.

 

[Scubaru]

I actually have seen that, it did open my eyes to a lot but I am still looking for some other details.

 

[MrAl]

Hello,

Some common transistors for starting out would be 2N2222, 2N3904, 2N3906 for example.