Transistor Can Packages; TO-18 Case style, Metal Can
TO-18 Metal Can
TO-18 is a through-hole device with a metal lid.
Terminal identification; Pin 1 Emitter, Pin 2 Base, Pin 3 Collector.
Note the location of the tab to the pins.
TO-18 Lead Location
Transistor Sockets are available for the TO-18 package and will also work for TO-92, TO-5, or TO-72 Devices.
The sockets are PC Mounting of differing sizes [1/4" Diameter X 1/4" High, is one example].
The required Heat Sink would be circular style to slide over the top of the metal can, normally secured with a
Thermal Adhesive.
Components that can be purchased in a TO-18 package include a 2N2222A NPN Transistor, or 2N2646 UJT to name just two.
Design note; Derating curves for a 2N2222A Transistor in a TO-18 package.
Types of Transistor cases; Transistor Packages.
Manufacturers of FETs and BJTs [Transistor Manufacturers]
How to Derate Transistors
