Elenco Green Projects - Manual (Page 8)

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About Your Snap Circuits ® Green Parts
The red & yellow LED’s (D1 & D5) are light
emitting diodes, and may be thought of as a
special one-way light bulb. In the “forward”
direction, (indicated by the “arrow” in the symbol)
electricity flows if the voltage exceeds a turn-on
threshold (about 1.5V for red and 2V for yellow);
brightness then increases. A high current will
burn out the LED, so the current must be limited
by other components in the circuit. LED’s block
electricity in the “reverse” direction.
RED & YELLOW LEDs HAND CRANK
CAPACITOR
The 470 μμF capacitor (C5) can store electrical
pressure (voltage) for periods of time. This
storage ability allows it to block stable voltage
signals and pass changing ones. Capacitors are
used for filtering and delay circuits.
The horn (W1) converts electricity into sound by
making mechanical vibrations. These vibrations
create variations in air pressure, which travel
across the room. You “hear”
sound when your ears feel
these air pressure
variations.
The clock (T2) contains a small crystal. When a
crystal is struck by an electronic pulse, it vibrates.
A microelectronic circuit makes the pulse and
measures the vibration rate. The vibration rate is
used as a time
standard, from
which minutes,
hours, and the
date are
calculated.
The pivot stand contains two resistors, 47 Ω and
10K Ω. Resistors “resist” the flow of electricity and
are used to control or limit the electricity in a
circuit. Materials like metal have very low
resistance (<1
Ω), while materials like paper,
plastic, and air have near-infinite resistance.
Increasing circuit
resistance reduces
the flow of
electricity.
SLIDE SWITCH
PRESS SWITCH
OTHER PARTS
The hand crank (HC) is a motor with a
gearbox attached. The gearbox
spins the motor shaft faster
but with less force
than you are
turning the
hand crank.
Hand Crank
The press switch (S2) connects (pressed, “ON”)
or disconnects (not pressed, “OFF”) the wires in
a circuit. When ON it has no effect on circuit
performance. It turns on electricity just like a
faucet turns on water
from a pipe.
Press Switch (S2)
The slide switch
(S5) connects
(ON) the center
snap to one of the
other two snaps.
When connected it has
no effect on circuit
performance. It directs electricity just like a value
controls water in a pipe.
Slide Switch (S5)
LED’s (D1) & (D5)
Capacitor (C5)
Horn (W1)
Clock (T2)
Pivot Stand