BJT Differential Amplifier

[alexfung1992]

Does anyone know how to build a simple BJT Differential Amplifier circuit? And also need to gain around 20..emergency please help. Thanks for that.

As I build a circuit but is not simple enough, please have a look for that and any comment for this circuit?

 

[phyzguy]

Try replacing Q1 and Q2 with two resistors.

 

[alexfung1992]

Try replacing Q1 and Q2 with two resistors.

I see, thanks a lot