I recently bought KSP 2N2222a npn transistors. The picture that I attach below shows the layout. The base of the transistor is applied a 1.5V which turns on the transistors and light up the bulb very brightly. However, I got a bulb that is so dim. The battery power and voltage is fine because I tested it and the led light up so brightly. What did I go wrong here or the transistors are fake?

Thank you

 

hi Mrss,
You should not apply a 1.5V voltage directly to the Base
You must have a current limiting resistors, you most likely have blown the 2N2222.

E

 

However, I got a bulb that is so dim ...

What are the ratings of this bulb compared to others? Maybe a higher voltage bulb?

 

The transistor needs a series resistor on the Base, like a 1K to 10K otherwise you will blow it up..