Elenco Electronics SNAP CIRCUITS SKILL BUILDER User manual

1
PROJECTS
1-57
MANUAL
58-126
ONLINE
INSTRUCTION
MANUAL
AGES
8+
Copyright © 2021 by Elenco®Electronics, Inc. All rights reserved. No part of this book shall be reproduced by any means; electronic,
photocopying, or otherwise without written permission from the publisher. U.S. Patents: 7,144,255; 7,273,377 & patents pending SOURCE CODE: SB-125V1
753124WEB
REV-A

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TABLE OF CONTENTS
Click through our table of contents to nd
the projects you want to build!
Project 58-59 p. 1
Project 60-69 p. 2
Project 70-79 p. 6
Project 80-89 p. 10
Project 90-99 p. 13
Project 100-109 p.18
Project 110-119 p.21
Project 120-126 p.26
Project Cut Outs p.30
2

1
Project 58 Lift Loss
Build the circuit to the left.
Cover the photoresistor (RP) and turn on the slide switch (S1).
The motor (M1) should spin. If not, give it a push to get it started.
Now uncover the photoresistor or get a ashlight and shine it on
the photoresistor. The motor will slow down as more light reaches
the photoresistor, and will stop spinning if enough light reaches the
photoresistor. This circuit demonstrates how darkness can be used
to control a fan. Try this circuit with and without the fan on the motor.
Project 59 Laser Blaster
This circuit demonstrates
how sounds can be made
for electronic games.
Build the circuit shown on the left.
When you turn on the slide switch (S1), the integrated circuit (U2)
should start sounding a laser gun sound. This integrated circuit is
designed to produce different sounds that can easily be changed. You
can even switch the sound on and off quickly to add sound effects to
your games or recordings.
WARNING: Moving parts. Do not touch the fan
or motor during operation.

2
Mind Reader Game
Build the circuit below. It uses a paper clip and a
3-Snap Wire as “shorting bars”.
Setup: Player 1 sets the target by placing the
3-snap shorting bar under the paper on column
2, 3 or 4. Player 2 must NOT know where the
shorting bar is located under the paper.
The object is for Player 2 to guess the location by
placing one end of the paper clip on the 5-snap
wire as shown, and the other end of the paper clip
at positions X, Y, or Z and then pressing the press
switch (S2). If Player 2 places the paper clip at
the correct position, the sounds played indicates
a “hit”. He keeps guessing until he hits. After each
hit, remove the 3-snap shorting bar and slide the
switch off and on to reset the sound.
Player 2 then sets the 2, 3, 4 side and player 1
tries his luck.
Play multiple rounds and see who gets the best
overall score. The winner will be the player who is
best at reading his opponent’s mind.
Paper Sheet to
hide position of
shorting bar
Project 60

3
Don’t Make a Sound
Use the circuit from Project 60, but now place a 3-snap wire and the
LED (D1) as “shorting bars” under the paper sheet as shown on left.
Setup: Player 1 sets the “Quiet Zone” by placing the 3-snap wire
and the LED (D1) under the paper on columns 2, 3 or 4, leaving only
one open. Player 2 must NOT know where these “shorting bars” are
located under the paper.
Both Player 1 and Player 2 are given 10 points. The object is for
Player 2 to guess the location of the “Quiet Zone” by placing the paper
clip at positions X, Y, or Z and pressing the press switch. If Player 2
places the paper clip on the correct column, and a sound plays when
he presses the press switch, this means he has not found the “Quiet
Zone” and he loses 1 point. He has three (3) tries to nd the zone on
each turn. Each time sounds are made he loses a point.
Player 2 then sets the 2, 3 or 4 side and player 1 starts searching. Play
continues until one player is at zero points and makes sound during
that players turn.
Discover the Diode
Diodes are electronic components that allow current to ow in only one
direction, blocking it in the other. The red LED (D1) is a special diode
that can emit light, and the transistor (Q1) can also be used as a pair
of diodes.
Turn on the slide switch (S1), the lamp (L1) will be bright and the
LED (D1) will be lit. The NPN transistor (Q2) is used here as a diode,
allowing the batteries to charge up the 470 mF capacitor (C5) and light
the LED.
Turn off the slide switch, the lamp will go dark immediately but the LED
will stay lit for a few moments as capacitor C5 discharges through it.
The transistor/diode isolates the capacitor from the lamp.
Project 61
Project 62
Paper sheet
to hide
position of
shorting bar

4
Mixed Up Music
Snappy says there sure are a lot of
different sounds that can be made
with the music and alarm ICs.
In the circuit, the outputs from the alarm and
music ICs are connected together. Build the
circuit shown and then place the alarm IC (U2)
directly over the music IC (U1), resting on two
1-snaps and a 2-snap. Turn on the switch (S1)
and you will hear a siren and music together
while the lamp (L1) varies in brightness.
Modify the last circuit by connecting points Y & Z with a 2-snap (on
level 5). The circuit works the same way but now it sounds like a
machine gun with music.
Project 64 Blaster Disaster
Now remove the 2-snap connection between Y & Z and then make
a 2-snap connection between X & Y (on level 5). The circuit works
the same way but now it sounds like a re engine with music.
Project 65 Siren & Song
Now remove the 2-snap connection between X & Y and then make
a 2-snap connection between W & X (on level 5). The circuit works
the same way but now it sounds like an ambulance with music.
Project 66 Ambulance Song
Project 63

5
Fuse or Lose
When you close the slide switch (S1), current ows from the batteries
through the slide switch (S1), the lamp (L1), motor (M1), and back to
the battery (B1). Pretend the 2-snap wire marked fuse in the drawing
on the left is a device that will open the circuit if too much current is
taken from the battery. When press switch (S2) is closed, the light is
shorted and motor speed increases due to an increase in current to the
motor. While still holding press switch (S2) down, remove the 2-snap
wire marked fuse and notice how everything stops. Until the fuse is
replaced, the open circuit path protects the electronic parts. If fuses did
not exist, many parts could get hot and even start res. Replace the
2-snap wire and the circuit should return to normal.
Many electronic products in
your home have a fuse that will
open when too much current is
drawn. Can you name some?
Space Battle
Build the circuit shown on the left. Turn on the switch (S1) and you will
hear exciting sounds, as if a space battle is raging!
The motor (M1) is used here as a 3-snap wire, and will not spin.
The preceding circuit is loud and may bother people around you,
so replace the speaker (SP) with the LED (D1). Make sure you
connect the LED with the positive (+) side on A6, not U3. Now you
have a silent space battle.
Project 68 Bizzare Blinker
Project 69
Project 67
WARNING: Moving parts. Do not touch the fan
or motor during operation.

6
People that are deaf need lights to tell them
when a doorbell is ringing. They also use
circuits like this to tell them if an alarm has
been triggered or an oven is ready.
Can you think of other uses?
Different sounds that can easily be
changed are very important when
designing games and toys.
Wave & Watch
This circuit does not use the noisy speaker (SP) but instead uses a
nice quiet LED (D1). Turn on the slide switch (S1), the LED ickers.
Wait a few seconds, and then cover the photoresistor (RP), and the
icker stops. The icker is controlled by the photoresistor; uncover it
and the icker resumes.
Switching Sounds
Build the circuit shown on the left. When you close the slide switch (S1),
the integrated circuit (U2) should start sounding an up-down siren. This
is just one more sound effect that this integrated circuit is designed to
produce. Switch the sound on and off quickly and see if you can create
even different effects. This mode will create many robotic sounds if
switched quickly.
Project 70
Project 71

7
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.
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.
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.
Pop On, Pop Off
Turn the slide switch (S1) on and off several times. You hear static
from the speaker (SP) when you turn off the switch.
Project 72 Project 73
Project 74
WARNING: Moving parts. Do not touch the fan
or motor during operation.
Current Splitter Light Up & Listen

8
Project 76
Little to Big
Place the fan on the motor (M1) and turn on the slide switch (S1), then compare
this circuit to Project #31. Push the press switch (S2), the lamp doesn’t light now
but the motor still spins.
The lamp is dark because the 100Wresistor (R1) limits the current through it. The
NPN transistor (Q2) uses the small lamp current to create a large current that spins
the motor.
Now replace the 100Wresistor (R1) with the larger 1KWresistor (R2). The motor
spins more slowly now, because the transistor cannot create as large of a motor
current from such a small controlling current.
The lamp is dark because the
photoresistor limits the current
through it. The NPN transistor uses
the small lamp current to create a
large current that spins the motor.
If you tried to control the motor speed
by placing the photoresistor in series
with the motor, the motor would not
spin because the photoresistor would
limit the current. But the photoresistor
can control the motor speed with help
from the transistor. You may need to
shine a light on the photoresistor (RP)
if the motor does not spin.
Compare this circuit to Project 75. It uses the
photoresistor (RP) to control the current to
the NPN transistor (Q2), instead of the press
switch (S2). You can adjust the speed of
the motor (M1) by changing how much light
shines on the photoresistor.
The motor doesn’t spin because the
100Wresistor (R1) limits the current
through it. The NPN transistor (Q2)
uses the small motor current to create
a large current that lights the lamp.
Now replace the 100Wresistor (R1)
with the larger 1KWresistor (R2). The
lamp is only slightly less bright even
though the motor current is much
lower.
Now place the 100Wresistor back in
the circuit and replace the press switch
with the photoresistor (RP). A bright
light on the photoresistor will turn the
lamp on. But if the light is dim, then
the photoresistor has high resistance,
so little current ows through the
transistor and the lamp is off.
Compare this circuit to Project 23. Push the
press switch (S2), the motor (M1) doesn’t
spin now but the lamp (L1) still lights.
Project 75
Project 77
WARNING: Moving parts.
Do not touch the fan or
motor during operation.
WARNING: Moving parts. Do not touch the fan or
motor during operation. Do not lean over motor.
Fan may not rise until switch is released.
Transistors, such as the NPN transistor (Q2), can amplify
electric currents. In this circuit, the small current through the
resistor is used to control a larger current through the motor. A
large resistor value limits the current through the lamp, making
it very dim, but the transistor amplied current is large enough
to still spin the motor.
Light to LightLuminate & Rotate