BC549C NPN Transistor

BC549C NPN Bipolar TransistorNPN Transistor Schematic Symbol

Alternatives that will definitely work in this design are BC549, BC548, BC547.  The 'C' suffix indicates a high gain grouping.  BC549 without the suffix might have either high or medium gain.  It makes no significant difference in this circuit.  The schematic symbol will often have a circle drawn around it, especially if it is a higher power transistor.  The transistor package is described as a TO-92. In the circuit, Q4 is used as a common emitter voltage amplifier and driver for the class B output stage.

Navigate Up