1. Base: At the bottom of the 4HS8 tube is a base, which serves as the connection point between the tube and the socket and holds the pins that make the electrical connection between the tube and the socket.
2. Elements: The 4HS8, like all vacuum tubes, consists of two or more elements. The elements consist of a cathode, which controls the current flowing through the tube, a grid, which controls the voltage that flows through the tube, and an anode, which is the terminal at the other end of the tube.
3. Envelope: The elements of the 4HS8 are enclosed in a glass or ceramic envelope. The envelope helps to protect the elements from dust, moisture and other contaminants.
4. Filaments: The filaments of the 4HS8 are two small pieces of wire that carry the electricity to the element’s cathodes. The filaments become hot when electricity passes through them, warming the tube and making it more efficient.