Vectronics VEC-422K - Manual (Page 7)

VEC-422K Owner's Manual SCA Decoder Kit
5
packaging. Larger plastic transistors and voltage regulators use a case backed
with a prominent metal tab to dissipate heat (T-220). Here orientation is
indicated by the positioning of the cooling tab.
Emitter
Flat Side
Metal Tab
Metal Can Device Plastic Device Tab-cooled Device
Integrated Circuits: Proper IC positioning is indicated by a dot or square
marking located on one end of the device. A corresponding mark is silk-
screened on the PC board and printed on the kit’s parts-placement diagram. To
identify specific IC pin numbers for testing purposes, see the diagram below.
Pin numbers always start at the keyed end of the case and progress
counterclockwise around the device, as shown:
1 2 3 4
8 7 6 5
Installation
Key
Key
Installation
Pin Numbers