User Manual

Project 99
Green Light
Turn on the slide switch (S1),
and the green LED (D2) lights.
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Replace the green LED (D2) with the red/yellow bicolor LED
(D10); try it in both directions (red on right, and yellow on right).
The speaker uses electromagnetism to create
changes in air pressure, which your ears feel
and interpret as sound. Think of the speaker
as creating pressure waves in the air just like
waves in a pool. You only see waves in the
pool when you disturb the water, so the
speaker only makes sound when the voltage
changes.
Turn the slide switch (S1) on and off several times. You hear static from
the speaker (SP2) when you turn the switch on or off.
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Project 101
Pop On, Pop Off
Project 100
Red/Yellow Light
LEDs are light emitting diodes, which
convert electrical energy into light. The
color of the light depends on the
characteristics of the material used in
them. The red/yellow bicolor LED is
actually a red LED and a yellow LED
connected in opposite directions inside
the same part.
LEDs are much more energy-efficient
than incandescent light bulbs, and can be
made very small.