untitled

Base pin

Emitter pin Collector pin

Figure 12-5:

The 2N3904

pinout.

Coil TB IC 1 Potentiometer TB Battery TB

Q1 LED TB

Figure 12-4:
Place the IC,
transistor,
and terminal
blocks
on the
breadboard.

Chapter 12: A Handy-Dandy Metal Detector 287