Experiment 1 - The Transistor Circuit
To understand how a transistor works, a simple circuit is enough.
Consider the circuit shown...
Simple transistor circuit.
The circuit has the typical behavior of a
Circuit diagram of a simple transistor circuit.
If the push-button switch S1 is open,
no voltage applies to the base
and no current flows into the base.
The transistor blocks
and the LED1 remains dark.
If you press S1,
a small voltage applies to the base,
and a small current flows through the base into the transistor.
The transistor is switches through
and the LED1 lights up.
A small current into the base of the transistor
has the result
that a much larger current flows through the transistor
from the collector to the emitter.
The base current is amplified!
However, this is not the only way
of how a transistor can amplify current,
or also voltage...