PNP Amplifier

Project Number: 125

OBJECTIVE: To compare transistor circuits.

Description: The PNP transistor (Q1) is similar to the NPN transistor (Q2) in Project #124, except that the electric currents flow in the opposite directions. When a small electric current flows from the emitter to the base, a larger (amplified) current will flow from the emitter to the collector. Build the circuit and slowly move up the adjustable resistor (RV) control. When the LED (D1) becomes bright, the lamp (L2) will also turn on and will be much brighter.