Elenco Circuit Maker Skill Builder 125 - Manual (Page 31)

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Project #50 Lingering Light
Project #51
Current Splitter
Project #52
Light Up & Listen
!
WARNING: Moving parts. Do
not touch the fan or motor during
operation.
Capacitors can store electricity and are
used to delay changes in voltage. They
can block unchanging voltages while
passing fast-changing voltages.
Transistors use a small current to
control a large current, and have three
connection points (the small current,
the larger current, and the combined
current). But they are actually
constructed using two diodes that are
connected together. These diodes are
similar to your LED (light emitting
diode) except that they don’t emit light.
Build the circuit and press the switch (S2). You see that the LED (D1)
turns off slowly after you release the switch.
This delay in turning off the LED is caused by the 470mF capacitor
(C5).
Turn on the switch (S1), the LED
(D1) and lamp (L1) are bright. This
is an unusual circuit which uses the
NPN transistor (Q2) as two
connected diodes to split the
current from the batteries into the
paths with the LED and lamp. If the
LED (D1) does not light, you may
have weak batteries in need of
replacement.
This circuit has four different
types of output. Flip the switch
(S1) several times. The LED
(D1) and lamp (L1) light up, the
motor (M1) spins, and the
speaker (SP) makes a siren
sound. If the LED does not light,
you may have weak batteries
that need replacement.
This is an unusual circuit which
uses the NPN transistor (Q2) as
two connected diodes, to split
the current from the batteries
(B1) into the paths with the LED
and lamp.
CM-125_Manual_031514.qxp_CM-125_Manual_031514 4/2/14 12:19 PM Page 31