Parts

Properties of some of the electronic components parts used in schematic diagrams on this website.

BC546B, BC547B, BC548B, BC556B, BC557B, BC558B

These are general purpose low power low frequent bipolar Si transistors. BC-546, 547 and 548 are NPN. BC-556, 557 and 558 are PNP.

NPN

TransistorVce max
BC 54680 V
BC 54750 V
BC 54830 V

BC548 on Wikipedia.

PNP

TransistorVce max
BC 55680 V
BC 55750 V
BC 55830 V

hfe

Suffixhfe
A250
B300
C500

1N4148

1N4148 on Wikipedia