Transistor Switching

Transistor
A transistor works much like a relay by switching electronic signals, except that it is much more sensitive and versatile. Today, we test the transistor to see how it differs from a relay. We start by building a simple momentary switch circuit to test the transistor and later switch the momentary switch for just two stand alone jump wires.

The yellow and blue wires that protruding upwards allows us to test the transistor with a simple touch of a finger. When electricity passes through the finger (low-resistance) the transistor receives the electricity and sends it to the LED, powering it as a result.

If you just add a little bit of moisture to your fingers, the LED will glow even brighter!