Elenco Electronics SC3DMEG Instruction Manual page 9

About Your Snap Circuits
SOUND MODULE
The melody IC (U32) contains a specialized
sound-generation integrated circuit (IC), a
small speaker, and a few
components. The IC has a recording of the
melody, which it makes into an electrical signal
for the speaker. The speaker converts the
signal into mechanical vibrations.
vibrations create variations in air pressure,
which travel across the room. You "hear"
sound when your ears feel these air pressure
variations.
LAMP
A light bulb, such as in the 4.5V lamp (L4),
contains a special thin high-resistance wire.
When a lot of electricity flows through, this wire
gets so hot it glows bright. Voltages above the
bulb's rating can burn out the wire.
The blue, blink red, and color2 LEDs (D9,
D11 & D12) are light emitting diodes, and may
supporting
be thought of as a special one-way light bulbs.
The
In the "forward" direction, (indicated by the
"arrow" in the symbol) electricity flows if the
voltage exceeds
brightness then increases. The blink red LED
contains a microcircuit that turns it on and off.
The color2 LED contains red, green, and blue
LEDs, with a micro-circuit controlling them. A
high current will burn out an LED, so the
current must be limited by other components
in the circuit (Snap Circuits
internal resistors added, to protect them in
case you make wiring mistakes). LEDs block
electricity in the "reverse" direction.
The clear motor (M4) converts electricity into
mechanical motion.
LEDs
a turn-on threshold
LEDs have
®
MOTORS
An electric current
Parts
®
through the motor will turn the shaft. It can
also be used as a generator, since it produces
an electric current when the shaft is turned.
How does electricity turn the shaft in the
motor? The answer is magnetism. Electricity
is closely related to magnetism, and an electric
current flowing in a wire has a magnetic field
similar to that of a very, very tiny magnet.
Inside the motor are several coils of wire with
many loops. If a large electric current flows
through the loops, the magnetic effects
become concentrated enough to move the
coils. The motor has a magnet inside, so as
the electricity moves the coils to align them
with the permanent magnet, the shaft spins.
The orange motor (M9) is a motor with a built-
in gearbox. The gearbox makes the shaft spin
slower but with greater force. Do not try to spin
its shaft manually to generate electricity
because you may break it. The middle snap is
only used for mechanical stability.
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