Elenco 130-in-1 Electronics Playground User Manual

ELECTRONIC

PLAYGROUNDTM

and LEARNING CENTER

MODEL EP-130

ELENCO®

Wheeling, IL, USA

Copyright © 2012, 2009 by Elenco® Electronics, Inc. All rights reserved.

REV-A Revised 2012

753039

No part of this book shall be reproduced by any means; electronic, photocopying, or otherwise without written permission from the publisher.

Important: If you encounter any problems with this kit, DO NOT RETURN TO RETAILER. Call toll-free [phone] or e-mail us at: [e-mail]. Customer Service • 150 Carpenter Ave. • Wheeling, IL 60090 U.S.A.

WARNING: Always check your wiring before turning on a circuit. Never leave a circuit unattended while the batteries are installed. Never connect additional batteries or any other power sources to your circuits.

WARNING:

!CHOKING HAZARD - Small parts. Not for children under 3 years.

Conforms to all applicable U.S. government requirements.

Batteries:

•Do not short circuit the battery terminals.

•Never throw batteries in a fire or attempt to open its outer casing.

•Use only 1.5V “AA” type, alkaline batteries (not included).

•Insert batteries with correct polarity.

•Non-rechargeable batteries should not be recharged. Rechargeable batteries should only be charged under adult supervision, and should not be recharged while in the product.

•Do not mix old and new batteries.

•Remove batteries when they are used up.

	• Do not mix alkaline, standard (carbon-	• Batteries are harmful if swallowed, so
	zinc), or rechargeable (nickel-
		keep away from small children.
	cadmium) batteries.

TABLE OF CONTENTS

Before We Begin	Page 4
Installing the Batteries	4
Making Wire Connections	5
Components	5
Building Your First Project	9
Troubleshooting	10
Helpful Suggestions	10
I. PLAYGROUND OF ELECTRONIC CIRCUITS	11
1. Woodpecker	12
2. Police Siren	13
3. Metronome	14
4. Grandfather Clock	15
5. Harp	16
6. Tweeting Bird	17
7. Meowing Cat	18
8. Callin’ Fish	19
9. Strobe Light	20
10. Sound Effects for Horror Movies	21
11. Machine Gun Oscillator	22
12. Motorcycle Mania	23
13. Vision Test	24
14. Patrol Car Siren	25
II. BASIC ELECTRONICS CIRCUITS	26
A MAJOR CHANGE	27
15. Dimming the Light	28
16. Flip Flopping	29
17. Capacitor Discharge Flash	30
18. Transistor Action	31
19. Series and Parallel Capacitors	32
20. Transistor Switching	33
21. Series and Parallel Resistors	34
22. Amplify the Sound	35

III. LED DISPLAY CIRCUITS		36
23. LED Display Basics		37
24. Digital Display Circuit for the Seven-Segment LED		38
25. LED Display with CdS and Transistor		39
26. Switching the LED Display Using Transistor Control		40
IV. WELCOME TO DIGITAL CIRCUITS		41
27.	“Flip-Flop” Transistor Circuit	42
28.	“Toggle Flip-Flop” Transistor	43
29.	“AND” Diode Transistor Logic with LED Display	44
30.	“OR” DTL Circuit with Display	45
31.	“NAND” DTL Circuit with Display	46
32.	“NOR” Transistor Circuit with Display	47
33.	“Exclusive OR” DTL Circuit	48
V. MORE FUN WITH DIGITAL CIRCUITS		49
34.	“BUFFER” GATE using TTL	50
35.	“INVERTER” GATE using TTL	51
36.	“AND” GATE using TTL	52
37.	“OR” GATE using TTL	53
38.	“R-S Flip-Flop” using TTL	54
39.	“Triple-Input AND” Gate using TTL	55
40.	“AND” Enable Circuit using TTL	56
41.	“NAND” Enable Circuit using TTL	57
42.	“NOR” Enable Circuit using TTL	58
43.	“NAND” Gate Making a Toggle Flip-Flop	59
44.	“Exclusive OR” GATE using TTL	60
45.	“OR” Enable Circuit using TTL	61
46. Line Selector using TTL		62
47. Data Selector using TTL		63

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VI. MEET TRANSISTOR-TRANSISTOR LOGIC	64
48. Blinking LEDs	65
49. Machiny Sound	66
50. Astable Multivibrator Using TTL	67
51. Tone Generator	68
52. Monster Mouth	69
53. Dark Shooting	70
54. A One-Shot TTL	71
55. Transistor Timer Using TTL	72
56. LED Buzzin’	73
57. Another LED Buzzin’	74
58. Set/Reset Buzzer	75
59. Another Set/Reset Buzzer	76
VII. OSCILLATOR APPLICATION CIRCUITS	77
60. Ode to the Pencil Lead Organ	78
61. Double-Transistor Oscillator	79
62. Decimal Point Strobe Light	80
63. “The Early Bird Gets the Worm”	81
64. Adjustable R-C Oscillator	82
65. Heat-Sensitive Oscillator	83
66. Pulse Alarm	84
67. Pushing & Pulling Oscillator	85
68. Slow Shut-off Oscillator	86
69. Electronic Organ Detector	87
VIII. MEET THE OPERATIONAL AMPLIFIER	88
70. Operational Amplifier Comparator	89
71. Changing Input Voltage	90
72. Non-inverting Dual Supply Op Amp	91
73. Inverting Dual Supply Op Amp	92
74. Non-inverting Amplifier	93
75. Dual-Supply Differential Amplifier	94
76. Miller Integrating Circuit	95
77. Stable-Current Source	96
78. Operational Amplifier Blinking LED	97
79. LED Flasher	98
80. Double LED Blinker	99
81. Single Flash Light	100
82. Introducing the Schmitt Trigger	101
83. Initials on LED Display	102
84. Logic Testing Circuit	103
85. Voice-Controlled LED	104
86. Buzzin’ with the Op Amp	105
87. Sweep Oscillator	106
88. Falling Bomb	107
89. Alert Siren	108
90. Crisis Siren	109
91. Op Amp Metronome	110
92. Burglar Buzzer	111

93. LED Initials	112
94. Wake Up Siren	113
95. Voice Activated LED	114
96. Logic Tester	115
IX. MORE FUN WITH OPERATIONAL AMPLIFIERS	116
97. Voice Power Meter	117
98. Reset Circuit	118
99. RC Delay Timer	119
100. Listen To Alternating Current	120
101. Pulse Frequency Multiplier	121
102. White Noise Maker	122
103. Light-Controlled Sound	123
104. DC-DC Converter	124
105. Super Sound Alarm	125
106. Op Amp Three-Input “AND” Gate	126
107. Timer	127
108. Cooking Timer	128
X. RADIO AND COMMUNICATION CIRCUITS	129
109. Operational Amplifier AM Radio	130
110. AM Code Transmitter	131
111. AM Radio Station	132
112. Crystal Set Radio	133
113. Two-Transistor Radio	134
114. Morse Code Oscillator With Tone Control	135
XI. TEST AND MEASUREMENT CIRCUITS	136
115. Water Level Warning	137
116. Water Level Alarm	138
117. Audio Signal Hunter	139
118. RF Signal Tracer	140
119. Square Wave Oscillator	141
120. Sawtooth Oscillator	142
121. Audio Continuity Tester	143
122. Audio Rain Detector	144
123. Audio Metal Detector	145
124. Water Level Buzzer	146
125. Pule Tone Generator	147
126. Resistance Tester	148
127. Transistor Tester	149
128. Sine Wave Oscillator	150
129. Sine Wave Oscillator With Low Distortion	151
130. Twin-T Oscillator	152
INDEX	153
PARTS LIST	155
DEFINITION OF TERMS	156
IDENTIFYING RESISTOR VALUES	159
IDENTIFYING CAPACITOR VALUES	159
METRIC UNITS AND CONVERSIONS	159

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BEFORE YOU START THE FUN!

Welcome to the thrilling world of electronics! Now that you have your Elenco® EP-130 Electronic Playground Kit, you can learn about electronics while doing 130 fun experiments. In this kit we have included everything you will need to start off on this electronics adventure, well except the batteries that is ☺.

As you go through this manual and do the experiments, you will notice that we have arranged the experiments, as well as information, into a logical progression. We will start off with easy circuits and then work toward the more intricate ones. Take your time and be sure to have some fun!

Each electronic component in the kit is connected to springs, so you can do all the circuit assembly without having to solder. To build a working project, all you have to do is connect the wires to the terminals as shown in each wiring sequence. There is no danger when doing these projects because you are using low voltage batteries, not the standard AC voltages.

Our simple instructions will show you how to operate the circuit for each experiment. A schematic diagram is also included, to help you learn how the circuit works. A schematic is simply a blueprint that shows how different parts are wired together. An image or symbols for each of the components in your kit are printed next to each piece.

As you will notice we refer to a Volt / Ohm Meter (VOM) for making measurements. A VOM or multimeter is a instrument that measures voltage, current (amperes or amps), and resistance (ohms-Ω). You will learn more about these in the upcoming pages. If you really want to learn about electronic circuits, it is vital that that you learn how to measure circuit values - for only then will you really understand electronic circuitry.

You do not have to have or use a VOM to do the experiments but you will find that it helps to better grasp how the circuits work. The VOM is a good investment if you plan to stay interested in electricity and electronics.

INSTALLATION OF BATTERIES

This kit requires six (6) “AA” batteries. To install the batteries to the back of your kit make sure to install them in the corresponding compartments. Put the + end and the – end correctly into the kit, the + end for the battery is the side that has the metal cap.

Remember: Never leave a dying battery or dead battery in your kit. Even if they are “leak-proof”, they still have the potential to leak damaging chemicals.

+

–

–+

++

––

–+

+

–

– +

+

+ –

–

– +

+

–

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WIRING CONNECTIONS

Provided in your kit are spring terminals and pre-cut wires, make the wires snap together for your use in the numerous projects. To join a wire to a spring terminal, just directly bend the spring over to one side and then install the wire into the opening.

When you have to join to two or three wires into a single spring terminal, be sure that the first wire does not come loose when you attach the second and third wires. The simplest way to do this is to place the spring onto the opposing side where you have connected the first wire.

Only insert the exposed or shiny part of the wire into the spring terminal. The electrical connection will not be made if the plastic part of the wire is inserted into the terminal. Removing the wire from the spring terminals is simply just bending each terminal and then pulling the wires out of it.

If the exposed metal ends of some of the wires break off due to great use, you should just simply remove 3/8” if the insulation from the wire of the broken end and then simply twist the strands together. To remove the installation you can use either a wire-stripper tool or a simple penknife. Be extremely careful when doing this because penknives are remarkably sharp.

COMPONENTS

This kit has more than 30 distinct components. If this happens to be your first time with electronics don’t fret over not knowing the difference between a resistor or a transistor, because the general purpose of each component will be described. The following explanations will help you comprehend what each component does and you will also gain more knowledge of each component as you do each experiment. There is also a parts list in the back of this manual, that way you can compare the parts in your kit with those recorded in the back.

Resistors: Why is the water pipe that goes to the kitchen faucet in your house smaller than the one from the water company? And why is the pipe smaller than the main water line that disburses the water to your entire town? Because you don’t need a lot of water. The pipe size controls the water flow to what you really need. Electricity works in the same manner, except that the wires have a minimal resistance that they would have to be particularly thin to limit the electricity flow. They would be solid enough to handle and break effortlessly. However, the flow of water through a large pipe could be restricted to by filling a part of the pipe with rocks (a

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fine screen would keep rocks from falling over), which would prolong the flow of water but not stop it completely. Like rocks are for water, resistors work in a similar way. They regulate how much electric current flows. The resistance, is expressed in ohms (Ω, named in honor of George Ohm), kilohms (kΩ, 1,000 ohms) or megohms (MΩ, 1,000,000 ohms) is a determination of how much resistor resists the flow of electricity. The water through a pipe can be increased by an increase in water pressure or the removal of rocks. In a similar way you can increase the electric current in a circuit by increasing the voltage or by the use of a lower value resistor (this will be shown in a moment). Below the symbol for the resistor is shown.

Resistor Color Code: The method for marking the value of resistance on a part is by using colored bands on each resistor. The representation of the first ring is the digit of the value of the resistor. The second ring is a representation of the second digit of the resistors value. The third ring means that you to which power of ten to multiply by, ( or the amount of zeros to add). The fourth and final ring is a representation of the construction tolerance. A majority of resistors have a gold band that represents 5% tolerance. Simply this means that the resistor value is guaranteed to be 5% of the valued marked. See the color chart on page 159.

Variable Resistor (Control): The variable resistor is simply a control and this is required in many electric circuits. The variable resistor can be used as a light dimmer, volume control, and in many other circuits when you are wanting to change resistance easily and quickly. A normal resistor is shown, this contains an additional arm contact that moves along the resistive material and can tap off the resistance desired.

Capacitors: Capacitors move alternating current (AC) signals while prohibiting direct current (DC) signals to pass. They store electricity and can function as filters to smooth out signals that pulsate. Capacitors that are small are traditionally used in high-frequency applications such as radios, transmitters, or oscillators. Larger capacitors ordinarily reserve electricity or act as filters. The capacitance (capacity for storing electricity) of a capacitor is expressed in a unit known as farad. An extremely large amount of electricity defines the farad. Most of the value of capacitors is predetermined in millionths-of-a-farad or microfarads.

Electrolytic - Electrolytic are the four largest capacitors. They are marked with an “–”. There is only one-way to connect them to the circuit, the + and the

– wires must always go into the correct terminals.

Disc - Unlike the electrolytic above, these capacitors have no polarity and can be connected in either way.

Disc Electrolytic

Tuning Capacitor: Ever wonder what that knob that changes the stations on your radio is? It’s a tuning capacitor. When the knob is rotated, the capacitance is changed. This alters the frequency of the circuit, letting through only one frequency and blocking out the rest.

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Diodes: Are like one-way streets. They allow the current to flow in only one direction. There are three of these in your kit. Your kit contains one silicon diode (marked Si) as well as two germanium diodes (marked Ge).

Transistors: Three transistors can be found in your kit. The part that makes each transistor work is a tiny chip, which is made of either germanium or silicon. There are a total of three connections points on each transistor.They are B, which stands for base, C, which stands for collector, and E, which stands for emitter. Mainly transistors are used to amplify weak signals. Transistors can also be used as switches to connect or disconnect other components as well as oscillators to permit signals to flow in pulses.

PNP NPN

The “8” LED display is mounted on a board and to prevent burning out the display with excess current, permanent resistors have been wired in.

Integrated Circuit: The transistor was invented in the 1940’s and after that the next big break through in electronics was in the 1960’s with the invention integrated circuit or the ICs. The advantage of this that the equivalent of hundreds or even thousands of transistors, diodes and even resistors can be placed into one small package.

Two types of ICs are used in this kit. They are the quad two-input NAND and the dual-operational amplifier, and you will have the chance to learn more about these in a bit.

Simple ICs will help you to understand enough to grasp the basic theories of more advanced ICs.

LEDs (Light Emitting Diodes): These are special diodes because they give off light whenever electricity passes through them. (The current can only pass through in one direction—similar to “regular” diodes).

LED Digital Display: Seven Light Emitting Diodes are arranged to create an outline that can show most letters of the English alphabet and all the numbers. An additional LED is added to represent a decimal point.

Cadmium Sulfide (CdS) Cell: This is what is known as a semiconductor, which practically resists electricity while it conducts. The resistance changes by the amount of light that is shined upon it.

Note: Provided is a light shield to use with the CdS cells, to use just simply place the shield over the cell, this helps to prevent light from leaving the cell.

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Antenna: This cylindrical component with a coil of fine wire wrapped around it is a radio antenna. If you’re wondering what the dark colored rod is, it’s actually mostly powdered iron. It’s also known as a “Ferrite Core”, which is efficient for antennas, and used in almost all transistor radios.

Transformer: Did you know that if you were to wrap two wires from different circuits around different ends of an iron bar, and if you were to add current in the first circuit, it will magnetically create current in the second circuit? That’s exactly what a transformer is! Transformers are used to isolate parts of a circuit, to keep them from interfering with each other.

If the iron bar in a transformer were allowed to rotate, it would become a motor. However, if a magnet within a coil is rotating then an electrical current is made; this is called a generator. Those two ideas may not seem important but they are the foundation of the present society. Pretty much all of the electricity used in this world is generated by huge generators, which are propelled by water pressure or steam. Wires transport energy to homes and businesses where it will be used. Motors are used to convert the electricity back into mechanical form so that it can be used to drive machinery and appliances.

Speaker: Did you know that electral energy is converted into sound through a speaker? By using the energy from an AC electrical signal it creates mechanical vibration. Sound waves, which are

created by variations of vibrations and then travel across the room. When you hear a sound it is actually your ears feeling the pressure from the air vibrations. To operate a speaker a high current and a low voltage are needed, so the transformer will also be used with the speaker. (A transformer can convert a highvoltage/low current to a low-voltage/high current).

Similar to the speaker, is the earphone. It is movable and more sensitive than the speaker, otherwise they are the same. The earphone you will be using is efficient as well as lightweight and can be used without taking away too much electrical energy from the circuit. Sound wise you will be using the earphone for weak sounds and for louder sounds the speaker will be used.

Batteries: The battery holders that are used in this kit are constructed to hold six (6) “AA” batteries.These batteries will be the supplier of all the power used in your experiments. When you connect the wires to the batteries make sure that you only connect the batteries to terminals noted. Terminals 119 and 120 provide 3 volts while terminals 119 and 121 provide 4.5 volts. Be aware that parts can be damaged (burned out) if you connect too much voltage (you can get up to 9 volts from the connections to the batteries) Be sure to make battery connections the right way.

Caution: Make sure your wiring uses the correct polarity (the “+” and “-” sides of the component)! Some parts can be permanently damaged if you reverse polarity.

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Switch: You know what a switch is – you use switches every day. When you slide (or flip) to the proper position, the circuit will be completed, allowing current to flow through. In the other position a break is made, causing the circuit to be “off”. The switch that we will be using is a double-pole, double-throw switch. You will learn about that later on.

Key: The key is a simple switch—you press it and electricity is allowed to flow through the circuit. When you release it, the circuit is not complete because a break is caused in the circuit’s path. The key will be used in most circuits often times in signaling circuits (you can send Morse code this way as well as other things).

Terminals: Two terminals will be used in some projects (terminals 13 and 14). They will be used to make connections to external devices such as an earphone, antenna or earth ground connection, special sensor circuits and so forth.

Wires: Wires will be used to make connections to the terminals.

Your parts and spring terminals are mounted on the colorful platform. You can see how the wires are connected to the parts and their terminals if you look under the platform.

YOUR FIRST PROJECT

A simple wiring sequence is listed for each project. Connect the wires with appropriate length between each grouping of terminals listed. When doing the experiment use the shortest wire that possibly gets the job done. New groupings will be separated by a comma, connect the terminals in each group.

As an example, here is the project 1 wiring sequence:

1-29, 2-30, 3-104-106, 4-28-124, 5-41-105, 27-88, 75-87-103-40, 115-42-119, 76-116, 121-22. Connect a wire between 1 and 29, another wire

between 2 and 30, another between 3 and 104 and then another wire between 104 and 106. Continue until all connections are made.

Caution: The last connection in each wiring sequence is an important power wire; this is deliberate. It is important that you make this connection your LAST connection. Damage can occur if one part of the circuit is completed before another. Therefore follow the wiring sequence exactly.

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TROUBLESHOOTING

You should have no problem with the projects working properly if you follow the wiring instructions. However, if you do encounter a problem you can try and fix it by using the following troubleshooting steps.These steps are comparable to those steps that electronic technicians use to troubleshoot complex electronic equipment.

1.Are the batteries being used new? If they are not, this may be your problem because the batteries could be too weak to power the project.

2.Is the project assembled properly? Check all the wiring connections to make sure that you have all the terminals wired correctly. Sometimes having someone else look at it helps to find the problem.

3.Are you following the schematic diagram and the explanation of the circuit? As your understanding and knowledge expands of electronics, you will be able to troubleshoot by following only a schematic, and once you add the description of the circuit you will be able to figure out your own problems.

4.If you have VOM, try taking some measurements of the voltage and current. You might be surprised just how handy a VOM really is.

5.Try building project 24 (Digital Display Circuit for the Seven-Segment LED). This is a very simple circuit that lights part of the LED display using only 2 wires.

Contact Elenco® if you still need help.

SUGGESTIONS TO HELP

Keep a Notebook

As you’re about to find out, you are going to learn many things about electronics by using this kit. As you learn, many of the things you discover in the easy projects will be built upon in later projects. We suggest using a notebook to help you organize the data you will be collecting.

This notebook does not have to be like the one you use in school. Think of it more as a fun notebook, that way you can look back on the all the projects you have done once you finish.

Wiring Sequence Marking

When you are wiring a project, especially those with lots of connections, you will find it helpful to mark off each terminal number as you connect the wires to it. Use a pencil and make light marks so that you can go back multiple times and re-read the sequence.

Collecting Components

You should start to make your own collection of electronic parts and therefore have your own scrap box of electronic parts.You can build your own circuits in or on top of a framework, box or container. You could use your circuit as a Science Fair project at school and even make a major research project from it.

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I. PLAYGROUND OF ELECTRONIC CIRCUITS

-11-

EXPERIMENT #1: WOODPECKER

For your first experiment you are going to make a	Notes:
circuit that that sounds like a woodpecker chirping.
Follow the wiring sequence carefully and observe the
drawings. Don’t forget to make all the proper
connections and have fun!
The simple circuit shown here does not have a key
or a switch, but you can easily add one. Replace
connection 124-28 with connections 124-137 and
138-28 to connect the key. Or, you can hook the
switch up by replacing 124-28 with connections 124-
131 and 132-28. Now you can easily turn off and on
the circuit. Go outside and see if you can attract birds
with it.
Want a different sound? Try varied combinations of
capacitance and resistance in place of the 100μF
capacitor and the 1kΩ resistor. To change the 100μF
		Schematic
capacitor to 470µF, disconnect terminal 116 and
transfer to terminal 118. Then, reconnect the wire
from 115 to connect to 117. Your “bird” might sound
like a cricket, or a bear!
Also, you can try using the 3V power supply.
Disconnect terminal 119 and connect it to terminal
123. Now your bird might sound like an English
sparrow. Feel free to experiment. Just don’t replace
the 47kΩ resistor with anything below 10kΩ,
because it might damage the transistor.

Wiring Sequence:

o 1-29

o2-30

o3-104-106

o 4-28-124

o5-41-105

o27-88

o75-87-103-40

o115-42-119

o76-116

o121-122

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EXPERIMENT #2: POLICE SIREN

Here is the first siren you are going to do – don’t be	Notes:
shocked if this experiment becomes the most famous
circuit in this kit.
This siren sounds like a real siren on a police car!
After the wiring is competed press the key. The tone
you eventually hear gets higher after pressing the
key. When you release the key, the tone gets lower
and then fades out.

Try some of these modifications:

1.If you change the 10μF capacitor to a 100μF or a 470μF it will give a very long delay for both turn off and turn on.

2.Change the circuit to remove the delays by temporarily disconnecting the 10μF capacitor.

Schematic

3. Change out the 0.02μF capacitor to a 0.01μF capacitor, and then to a 0.05μF capacitor.

Wiring Sequence:

o 1-29 o 2-30

o 3-103-109 o 4-119-137

o5-47-110

o46-104-90

o114-48-120

o85-138

o86-89-113

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EXPERIMENT #3: METRONOME

Learning to play a musical instrument? Then you	Notes:
might find this experiment helpful. This is an
electronic version of the metronome, used by musical
students and musical geniuses alike, worldwide.
If you press the key, you hear a repeating sound from
the speaker. Turn the control knob to the right and
you’ll hear the sound “get faster” as the time between
sounds shortens.
Try swapping out the 4.7kΩ resistor with different
one. Also, you might want to try a different capacitor
in place of the 100μF capacitor too see what effect it
will have. Are you still keeping notes?
If you would like to hear the difference that a stronger
capacitor makes, try connecting the 470μF capacitor
to the batteries. Connect terminal 117 to 119 and
terminal 118 to terminal 120. You might need to
adjust the control to maintain the same pulse rate.

Schematic

Wiring Sequence:

o 1-29

o2-30

o3-104-116

o 4-28-138

o5-41-103

o27-80

o40-115-79

o42-119

o120-137

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EXPERIMENT #4: GRANDFATHER CLOCK

	Does your home lack a grandfather clock? Well not	Notes:
	any longer, with this experiment you will make your
	own electronic grandfather clock.
	This circuit will produce clicks at approximately one-
	second intervals. The sound and timing together
	might remind you of an old grandfather clock. If you
	would like for it to go faster or slower then you can
	change out the 100kΩ resistor.
	The steady ticking can put animals (and people) into
	a sleepy state of mind. If you have ever traveled on a
	train, you remember how sleepy you get from
	hearing the clicking sound of the wheels.
	Ever scare a clock out of ticking? Shout directly into
	the speaker. You can briefly stop the clock! The
	speaker acts like a microphone as well. The sound
		Schematic
	of your voice vibrates the speaker and disturbs the
	electrical balance of the circuit, briefly.

Wiring Sequence:

o 1-29 o 2-30

o 3-104-116 o 4-90-120

o5-41-103

o40-72

o42-119

o 71-89-115

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EXPERIMENT #5: HARP

Have you ever wanted to make music just by waving	Notes:
your hand? Well that is just what you are going to be
doing. How does this magic work? Well, the tones
change based upon the amount of light that gets to
the CdS cell. With a bright light the tone is higher but,
if you cover the CdS with your hand, the sound gets
lower.
Since the early days of vacuum-tube circuitry, this
method of creating musical sound has been used.
Leon Theremin was the inventor of this type of
instrument, thus the instrument has been named the
Theremin in his honor.
After the wiring has been completed press the key
and then wave your hand over the CdS cell. You will
soon be able to play music with this magical
electronic instrument after just a bit of practice. Use		Schematic
your CdS cell light shield and use it to experiment for
more light control. Most importantly HAVE FUN!

Wiring Sequence:

o 1-29 o 2-30

o 3-16-41-109 o 4-120

o5-106-110

o15-87

o40-105-88

o 42-137 o 119-138

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EXPERIMENT #6: TWEETING BIRD

In this experiment you are going to make a circuit	Notes:
that that sounds like the mockingbird.
Follow the wiring sequence and observe the
drawings. Don’t forget to make all the proper
connections and have fun!
To finish the circuit below, slide the switch to the A
position to turn on the power. No sound will come
from the speakers yet. When you press the key you
will hear a sound quite like a bird chirping from the
speaker. When you release the key, you will still be
able to hear the chirping sound but eventually it will
slow down and stop. The first transistor “Q1” is
dropped off from the battery when the key is
released.Transistor “Q2” still produces the bird sound
until the controlling current from transistor “Q1” stops.
Try using a different value capacitor instead of the		Schematic
10μF and the 100μF capacitors. These capacitors
control the amount of electricity reaching the
transistors. Listen for the difference. Make sure to
start keeping notes on your experiments.

Wiring Sequence:

o 1-29

o2-30

o3-106-110

o 4-41-131-138

o5-44-109

o40-114-91-75

o42-85

o43-105-86-77

o119-45-115-113-92

o76-137

o78-116

o120-132

-17-

EXPERIMENT #7: MEOWING CAT

Are you bothered by mice, do you not have a	Notes:
mousetrap? You should try this next experiment to
help you instead—see if the sound of this cat can
keep the pests out of your life.
Just follow the drawing below and the wiring
sequence. To start the experiment switch the set to
B. Press down on the key and release it immediately.
You will hear the meow from the cat coming from the
speaker. If you adjust the control knob while the cat’s
meow is fading away, what effect on the circuit
operation does it have? Now set the switch to A and
try it once more. Now it sounds as if the cat is
begging for a dish of milk in a low, long sounding
		Schematic
tone.
To produce a variety of sounds try experimenting
with this circuit. Whatever you do just don’t change
the value of the 0.05μF capacitor to more than 10μF
or reduce the value of the 10kΩ resistor— or else the
transistor could get damaged.

Wiring Sequence:

o 1-29

o2-30

o3-41-109

o 4-72-82-132-114

o5-106-110

o27-40-105

o115-113-42-119

o71-138

o81-28

o116-131

o120-137

-18-

EXPERIMENT #8: CALLIN’ FISH

Did you know that many marine animals	Notes:
communicate to each other using sound? I bet you
have heard that dolphins and whales use sound for
communication, but what you probably don’t know is
that they are not the only ones. Due to research we
are able to find out that some fish are attracted to
certain sounds. Making this circuit, will allow you do
to some research of your own.
Once you make the last connection you are turning
on the power. You should be able to hear pulses of
sound coming from the speaker. The sound changes
by turning the control. This circuit is a type of audio
oscillator circuit, which you will learn more about later
in this book.
If you have a fish tank at home or at school you
should place your kit near the glass to see if the fish
are attracted to the sound. Are they?
If you like to fish, you should try this out while fishing.
What you need to do is attach another speaker to
		Schematic
terminals 1 and 2 using long lengths of insulated
wire. Wrap the speaker carefully in a waterproof
plastic bag or place it in a tightly sealed jar. Make
sure that no water is able to reach the speaker. Lower
the speaker into the water, cast your fishing line, and
see if you catch anything.

Wiring Sequence:

o 1-29 o 2-30

o 3-93-100-110 o 4-120

o5-41-109

o27-94

o 28-40-99 o 42-119

-19-

EXPERIMENT #9: STROBE LIGHT

In this experiment you will be creating an oscillator	Notes:
circuit that doesn’t make sound using a speaker or
an earphone. Instead the circuit will produce light
with an LED. This will give you an idea of how larger
strobe lights work. When you press the key, watch
LED 1. At certain intervals the light turns on and off.
With the 50kΩ control you can control the rate of
blinking.
Try substituting a capacitor with a lower value for the
100μF capacitor to see how an oscillator works.
Make a prediction about what you think will happen?
Were you correct?

Schematic

Wiring Sequence:

o 3-115

o4-27-138

o5-31

o28-80

o33-47

o79-116-112-46

o111-48-121

o119-137

-20-

EXPERIMENT #10: SOUND EFFECTS FOR HORROR MOVIES

The sounds that you will hear from this circuit will remind you of the music you hear in horror movies. Once you wire the project, use your special light shield and your hand to change the light amount that shines onto the CdS cell. This changes the pitch of the music.

The pitch of a sound is determined is by the sound wave’s frequency, which is the number of cycles of electromagnetic energy per second. The amount of light on the CdS cell determines the resistance of the cell. The more resistance you have the slower the frequency of the musical sound waves. The oscillator circuit produces the basic sound wave.

Frequency modulation, or FM, is when the frequency of an oscillator is controlled by part of the circuit. An FM radio signal is similar to this but at higher frequencies.

Notes:

Schematic

Wiring Sequence:

o 1-29

o2-30

o3-47-106

o 4-74-45-42-119

o5-103-105

o15-86

o16-46-104

o40-113-80

o41-112-78

o44-114-83-76

o120-48-81-79-75-77

o73-85-84

-21-

EXPERIMENT #11: MACHINE GUN OSCILLATOR

This circuit is what engineers refer to as a “pulse oscillator”. It will make machine gun like sounds.

There are many different ways to make oscillators. In this kit, you will build several of them and later on, you will be told on how they work. In the meantime, we will just tell you what an oscillator is.

An oscillator is a circuit that goes from high to low output on its own, or in other words, it turns itself on and off. A pulse oscillator is controlled from pulses, like the pulses made from a capacitor charging and discharging. The oscillator in this kit turns off and on slowly. However, some oscillators turn off and on many thousands of times per second. Slower oscillators can often be seen controlling blinking lights, such as turn signals in a car or truck. “Fast” oscillators are used to produce sound. The fastest oscillators produce radio frequency signals known as “RF signals”. The RF signal oscillators turn on and off millions of times per second!

The amount of times an oscillator turns off and on each second is called the frequency of the oscillator. Frequency is measured in units called hertz (Hz). The frequency of this oscillator is about 1 to 12Hz. The frequency of a radio signal oscillator would be measured in either MHz (megahertz, meaning a million hertz) or kHz (kilohertz, meaning a thousand hertz).

Once you finish wiring, press the key to start the oscillator. The 50kΩ resistor is the control; you can swap it out with other resistors to change the sound from a few pulses per second to a dozen or so per second. Also, you can change the frequency of this oscillator circuit by swapping out other capacitors in place of the 10μF. Remember to observe the correct polarity!

Notes:

Schematic

Wiring Sequence:

o1-29

o2-30

o3-110-114

o4-27-138

o5-41-109

o28-82

o40-113-81

o42-119

o121-122

o124-137

-22-

EXPERIMENT #12: MOTORCYCLE MANIA

Have you ever tried to steer a bicycle or a motorcycle with just four fingers? This would be dangerous on a real motorcycle but on electronic version it is a lot of fun!

To do this project, connect the components following the wiring sequence. Next grasp the metal exposed ends of the two long wires (connected to terminals 110 and 81) in between your index finger and thumb of your left and right hands. Now vary your grip/pressure and listen as the sound changes in the speaker. Due to the grip you use the sound changes.

You can create different sounds by controlling the light that into the CdS cell. If you have a strong light on the CdS cell you can control the entire operation by putting more pressure on the wires within your hands. Make a shadow over the CdS cell with your hand and see what happens.

By holding the ends of the wires, you are making yourself an extension of the circuitthus a human resistor. When you change your grip the resistance changes in the projects current. The sound from the circuit will make a real motorcycle noise and with practice you can do it real well. By doing this you can make the motorcycle idle as well as race.

Wiring Sequence:

o 1-29

o2-30

o3-16-105-109

o 4-120

o5-41-106

o15-82

o40-110-WIRE

o42-119

o81-WIRE

WIRE

Experiment with different values for the 0.1μF and 0.05μF capacitors, but make sure you don’t use values above 10μF or you may damage the transistor.

Notes:

Schematic

-23-

EXPERIMENT #13: VISION TEST

This circuit produces short pulses. After you close		Notes:
the key, the LED display shows 1 for a second and
then turns off, even when you keep pressing the key.
You could create a game with this circuit. Display a
number or a letter on the LED display and then have
the players tell you what number it is. You change
numbers or letters on the display by just changing
the wiring to the display. Connect the terminals to
form the letters or numbers to terminal 71 (in the
place of the 21 and 23 terminals). Connections for
the number 3 would be 17-21-22-23-20-71.
You can try different values of capacitors to see their
effects. Don’t use a capacitor with a value higher than
10μF or the excessive current can damage the
transistor.

Schematic

Wiring Sequence:

o21-23-71

o25-124-137

o40-73

o41-72

o82-83-42-119

o74-81-111

o84-112-138

o121-122

-24-

EXPERIMENT #14: PATROL CAR SIREN

With this experiment you may want to be careful not	Notes:
to confuse your neighbors. This experiment sounds
as like a loud siren just like the real sirens on police
cars and ambulances. The tone is initially high but as
you close the key the tone gets lower. You are able
to control the tone just as the police and ambulance
drivers do.
The oscillator circuit being used is the same type
used in many other experiments in this kit. Press the
key and another capacitor is added to the circuit to
slow the action of the oscillator circuit.

Schematic

Wiring Sequence:

o 1-29

o2-30

o3-104-106-110

o 4-85-120

o5-41-109

o40-137-105-86

o103-138

o42-119

-25-

II. BASIC ELECTRONICS CIRCUITS

-26-

A MAJOR CHANGE

Until now, in addition to the wiring sequences you have had drawings to help guide you in the wiring connections. The rest of the projects will have just the schematic diagram without the circuit drawings.

A schematic diagram is like a road map but it is used for electronic circuits. It shows you how different parts connect together and how electricity flows through a circuit. Electronics engineers and technicians use schematics to help guide them through circuits.

You don’t need to build your circuits from the schematic diagrams by themselves. We have added the number of terminals to where you will be making the wiring connections on each schematic, to help you out - a line between numbers on the schematic means that you should connect a wire between those terminals in your kit. Every part in your kit has a schematic symbol all of its own. At the beginning of this manual you will find a picture of each part with its schematic symbol as well as a short description.

As you will start to notice, the schematics have some lines that cross each other and that there is a dot at the crossing point. This means that the two wires which are represented by the lines, are to be connected at the point where the dot is located (you will find the terminal number next to the dot). If there is not a dot where the lines cross, this means that the wires do not connect (you won’t see a terminal number if the wires don’t cross).

Lines Are Connected / Lines Not Connected

The schematic diagrams will look confusing at first but they are simple once you have some practice using them. Don’t get discouraged if you get confused at first. You will be constructing circuits in no time by just looking at the schematic diagrams.

To be able to read schematic diagrams is important for anyone getting into the field of electronics. Many electronics books and magazines display intricate circuits only in schematic form. A schematic is also shorter and more accurate way to show a circuit rather than a written form.

-27-

EXPERIMENT #15: LIGHT DIMMER

Ever thought you could use a capacitor to dim a light? Try this project. After you finish the wiring, set the switch to A. Then the LED segments will light up slowly and show an L. Once the LED reaches its brightest point it will stay on. Move the switch to B and watch as the L fades away.

Look at the schematic. When the switch is on, the current flows from the battery to the 100μF capacitor to charge. Once the capacitor reaches full charge, electricity flows to the transistor base and turns it on gradually, which turns the LED on. Eventually the capacitor will be completely charged and then the current flows continuingly to the base of the transistor and the LED stays on.

When the switch is turned off and you remove the battery from the circuit, then the capacitor starts to discharge through the transistor and the LED. The L dims until the discharge of the 100μF is finished.

If you want a slower dimmer circuit, all you have to do is replace the 100μF capacitor with the 470μF capacitor. Replace connections 25-116-124 with connections 25-118-124. Be patient because the LED does eventually come on.

Go back to project 2 (the police siren) and see if you can figure out why the siren goes from high to low as you press and then release the key.

Hint: the 10μF capacitor charges when you close the key.

Notes:

Schematic

Wiring Sequence:

o 18-19-20-48 o 25-116-124 o 46-115-90 o 119-47-131 o 89-132

o 121-122

-28-

EXPERIMENT #16: FLIP FLOPPING

How about we take a break? This circuit is for	Notes:
entertainment. The numbers 1 and 2 will flash on the
display in the circuit. This might remind you of some
neon signs that have eye-catching advertisements
on them.
A “flip-flop” circuit controls the LED display in this
experiment. In later projects you will be learning more
about flip-flop circuits. Try a different value for the
capacitors to see the effects on the operation speed.
Try and rewire the LED display to flash numbers
other than 1 and 2. Try placing higher values in place
of the 22kΩ and 4.7kΩ resistors. Do not use lower
values for any of the resistors or else you could
damage the transistors.

Wiring Sequence:

o17-19-20-22-41-116-82

o21-42-45-119

o23-44-118-84

o79-81-83-85-25-124

o80-117-40

o86-115-43

o121-122

Schematic

-29-

EXPERIMENT #17: CAPACITOR DISCHARGE FLASH

In this circuit single pulses of high voltage electric energy are generated by suddenly discharging a charged capacitor through a transformer. Automobile ignition systems use a similar capacitor-discharge reaction.

The operation of this circuit is simple but the concepts involved are important to helping you understand more complicated circuits. If you have access to an oscilloscope, you can scientifically measure the energy that is discharged through the transformer.

The 470μF capacitor stores up energy as the batteries supply millions of electrons to the capacitors negative electrode. Meanwhile the batteries draw the same number of electrons from the capacitors positive electrode so that the positive electrode is lacking electrons. The current must pass through the 4.7kΩ resistor, so it requires at least 12 seconds for the capacitor to receive the full 9V charge from the batteries.

The amount of charge a capacitor can store depends on its capacitance value and the voltage applied across it. This represents the amount of electrons displaced in the electrode.

The amount of electrons in a capacitor’s electrode is measured in coulombs. The quantity of one coulomb is 6,280,000,000,000,000,000 electrons (6.25 x 1018).

The charge in either electrode of the capacitor is determined by multiplying the capacitance (C) by the voltage across the capacitor (E). (Q = C x E). The 470µF (470 x 10-6F) capacitor at 9V is calculated as follows:

Q = C x E = 470 x 10-6 x 9 = 4.23 x 10-3 coulombs

or:

470 x 0.000001 x 9 = 4.23 x 10-3 coulombs (265,564,400,000,000 electrons)

Pressing the key causes the above number of electrons to pass through the transformer winding in a very short time and induces a high voltage in the secondary winding. Thus causing the LED to flash.

An oscilloscope is an electronics measurement instrument used by engineers and technicians. If you have access to one, connect it (with help from someone who knows how to use it) to terminal 3 and terminal 5 of the transformer to indicate the presence of 90V or more. The indicated voltage is produced

when the charge held by the capacitor is released into the transformer.

Notes:

Schematic

Wiring Sequence:

o1-138

o2-118-124

o3-31

o5-33

o79-119

o80-117-137

o121-122

-30-