Figure 2-3. Transistor Representations
2-10. The very first transistors were known as point-contact transistors. Their
construction is similar to the construction of the point-contact diode covered in chapter 1.
The difference is that the point-contact transistor has two P or N regions formed instead of
one. Each of the two regions constitutes an electrode (element) of the transistor. One is
named the emitter and the other is named the collector (see Figure 2-4, view (A)).
Figure 2-4. Transistor Constructions
2-11. Point-contact transistors are now practically obsolete. They have been replaced by
junction transistors, which are superior to point-contact transistors in nearly all respects.
The junction transistor generates less noise, handles more power, provides higher current
23 June 2005