Which transistor can be connected in place of a 2N3904?

Question

which transistor can be connected in place of a 2N3904......

i m making a light blnking circuit.....

can i use a BC547 or a 1558 in place f it.

Answer 1

Yes you can use the BC547.  The electronic properties are the same, but the physical configuration of the base, collector and emitter may different than the 2N3904.  Verifiy the base, emitter and collector terminations and alter the circuit as needed.