Popular transistors.

BC556 transistor.
Pinout. Datasheet.

Marking: BC556.
Package: TO-92, 1-collector, 2-base, 3-emitter.
Material of transistor: Si
Polarity: PNP
Total Devise power dissipation |PD|: 0.625 W
Collector-base breakdown voltage |VCBO|: 80V
Collector-emitter breakdown voltage |VCEO|: 65V
Emitter-base breakdown voltage |VEBO|: 6V
Maximum collector current |Ic max|: 0.1A
Maximum junction temperature |Tj|: +150 °C
Transition frequency (ft) : 280MHz(typ.)
Emitter Capacitance |Ce|:10pF
Colector Capacitance |Cc|:3pF
Collector-emitter saturation voltage|VCE|:0,075V(IC=10mA,IB=0,5mA),
0,25V(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| : 125-500,(IC=2mA,VCE=5V), 240-500(BC556B)
Noise Figure, (NF): 2-10dB