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Diodes are commonly used to Sometimes, we put LED’s in shapes
change AC current into DC current. to make numbers or letters on
These are called rectifiers. digital displays, like on a digital
Another common use is in radio clock. If your clock lights up in
receivers for transforming the AC color, it’s probably an LED display
radio signal into a signal that can (black on grey are LCD displays,
be turned into audio that we can not LED).
hear.
There are different types of diodes,
but they all share this one-way
valve characteristic. One special
kind of diode is the LED, or Light
Emitting Diode. These are the
colored (or white) “lights” that are
used on so many things these
days. They are diodes that have
been specially designed to emit
light of a certain color when you
put electricity through them. They
have polarity because they need to Transistors
be connected just like any other The transistor is a small electronic
diode. We generally just use them component that has radically
to make light, but they still only let changed your life. It has made
current through one way. We’ll be most of the electronic items we use
doing a bunch of experiments with today (like computers, cell phones,
LEDs, so just know that they come etc.) possible.
in many different sizes and colors.
A transistor
is kind of
like an
electronic
dimmer
switch.
Think of a light dimmer – you
know, the kind that you might
have on the lights in a room in
your house, or a friend’s house.
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