Elenco Upgrade Kit SC100 to SC750 - Manual (Page 17)

-16-
Project #124
OBJECTIVE: To compare transistor circuits.
There are three connection points on an NPN transistor (Q2), called
base (marked B), emitter (marked E), and collector (marked C). When
a small electric current flows from the base to the emitter, a larger
(
amplified) current will flow from the collector to the emitter. Build the
circuit and slowly move up the adjustable resistor (RV) control. When
the LED (D2) becomes bright, the lamp (L2) will also turn on and will
be much brighter.
NPN Amplifier
Project #125
OBJECTIVE: To compare transistor circuits.
The PNP transistor (Q1) is similar to the NPN transistor (Q2) in project
#166, 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.
PNP Amplifier