Popular transistors.

BC557B transistor.
Pinout. Datasheet.

Type Designator: BC557B.
Package: TO-92, 1-collector, 2-base, 3-emitter.
Material of transistor: Si
Polarity: PNP
Total Devise power dissipation |PD|: 0.5W(at ambient temperature ≤ + 25 )
Collector-base breakdown voltage |VCBO|: 50V
Collector-emitter breakdown voltage |VCEO|: 45V
Emitter-base breakdown voltage |VEBO|: 5V
Maximum collector current |Ic max|: 0.1A
Maximum junction temperature |Tj|: +150 C
Transition frequency (ft) : 100MHz(min)
Collector-Base Capacitance |Ccbo|:6pF
Collector-emitter saturation voltage|VCE|:0,06V(IC=10mA,IB=0,5mA),
0,18V(IC=100mA,IB=5mA)
Base-emitter saturation voltage|VBE|:0,75V(IC=10mA,IB=0,5mA),
0,93V(IC=100mA,IB=5mA)
Forward current transfer ratio |hFE| : 220-457,(IC=2mA,VCE=5V)
Noise Figure, (NF): 2-10dB