What can i do with 4 pins transistors . The fourth pin is called " shield " I think . Can I just cut it or I have to solder that pin somewhere ? Examples of transistor : af137 and af138 .
You can leave it unconnected or connect it to ground. If you cut the lug is fine, thats what I do with my transistors.
Seconded! I usually snip them off so they don't short anything out.
Thanks for the answers ;)