Complete Electronics Self-Teaching Guide with Projects
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56. An oscillator is a circuit that emits a continuous sine wave output without requiring an input signal. Other types of oscillators exist that do not have sine wave outputs, but they are not discussed in this book. (Chapter 9, introduction)
57. Positive feedback causes the amplifier to sustain an oscillation or sine wave at the output. Negative feedback causes the amplifier to stabilize, which reduces oscillations at the output. (Chapter 9, problems 2 and 3)
58. A capacitive voltage divider (Chapter 9, problem 14)
59. An inductive voltage divider (Chapter 9, problem 14)
60. See Figure 12.15.
Figure 12.15
(Chapter 9, problem 24)
61. See Figure 12.16.
Figure 12.16
(Chapter 9, problem 25)
62. (Chapter 9, problem 11)
63. See Figure 12.17.
Figure 12.17
(Chapter 10, problem 4)
64. Primary and secondary (Chapter 10, problem 2)
65. Vin/Vout = VP/VS = NP/NS = TR (Chapter 10, problem 6)
66. Iout/Iin = IS/IP = NP/NS = TR (Chapter 10, problem 13)
67. Zin/Zout = (NP/NS)2, or impedance ratio, is the square of the turns ratio. (Chapter 10, problem 16)
68. They are used for stepping up or stepping down an AC voltage, and to match impedances between a generator and a load. (Chapter 10, introduction)
69. See Figure 12.18.
Figure 12.18
(Chapter 11, problem 14)
70. See Figure 12.19.
Figure 12.19
(Chapter 11, problem 31)
71. R1 = 84 ohms, C1 = 622 μF, C2 = 265 μF (Chapter 11, problems 26–29)
Appendix A
Glossary
Ampere (A)
The unit of measurement of electric current.
Amplifier
Electronic device or circuit that produces an output signal with greater power, voltage, or current than that provided by the input signal.
Capacitance (C)
The capability of a component to store an electric charge when voltage is applied across the component, measured in farads.
Capacitor
A component that stores electric charge when voltage is applied to it. It can return the charge to a circuit in the form of an electric current when the voltage is removed.
Current (I)
The amount of electric charge flowing through a circuit, measured in amperes.
Diode
A component that conducts current in one direction only.
Discrete components
Individual electronic parts such as resistors, diodes, capacitors, and transistors.
Farad (F)
The unit of measurement of capacitance.
Feedback
A connection from the output of an amplifier back to the input. In some instances, a portion of the output voltage is used to control, stabilize, or modify the operation of the amplifier. However, in some instances, unwanted feedback can cause a squealing noise or can cancel another signal.
Filter
Electronic circuit that can either block or pass frequencies that fall within a certain range.
Frequency (f)
Number of cycles of a waveform that occurs in a given time period, measured in hertz (cycles per second).
Ground
Zero volts. This is the arbitrary reference point in a circuit from which all voltage measurements are made.
Henry (H)
The unit of measurement of inductance.
Impedance (Z)
Total opposition (resistance and reactance) of a circuit to alternating current (AC) flow, measured in ohms.
Inductance (L)
The property of a component that opposes any change in an existing current, measured in henrys.
Inductor
A coil of wire whose magnetic field opposes changes in current flow when the voltage across the coil is changed.
Integrated circuit (IC)
Electronic component in the form of a small silicon chip in which numerous transistors and other components have been built to form a circuit.
Kirchhoff's laws
A set of formulas that form the basis for direct current (DC) and alternating current (AC) circuit analysis. This includes Kirchhoff's current law (KCL), which states that the sum of all currents at a junction equals zero; and Kirchhoff's voltage law (KVL), which states that the sum of all voltages in a loop equals zero.
Ohm (Ω)
The unit of measurement of resistance.
Ohm's law
A formula used to calculate the relationship between voltage, current, and resistance, expressed as V= IR. Also expressed as E = IR.
Operational amplifier (op-amp)
An integrated circuit, multistage amplifier. An op-amp is much smaller and, therefore, more practical than an equivalent amplifier made with discrete components.
Oscillator
An electronic circuit that produces a continuous output signal such as a sine wave or square wave.
Phase angle
For a signal, the angle of lead or lag between the current waveform and the voltage waveform, expressed in degrees.
Phase shift
The change in a phase of a signal as it passes through a circuit, such as in an amplifier.
Pinout
The configuration of leads used to connect an electronic component to a circuit.
Power
The expenditure of energy over time, measured in watts.
Reactance (X)
The degree of opposition of a component to the flow of alternating current (AC), measured in ohms. There are two types of reactance: capacitive reactance (XC) exhibited by capacitors and inductive reactance (XL) exhibited by inductors.
Rectification
The process to change alternating current (AC) to direct current (DC).
Resistance (R)
The degree of opposition of a component to the flow of electric current, measured in ohms.
Resistor
A component whose value is determined by the amount of opposition it has to the flow of electric current.
Resonance frequency
The frequency at which the reactance of a capacitor and inductor connected together in a circuit are equal.
Saturated transistor
A transistor that is completely turned on.
Semiconductor
A material that has electrical characteristics of a conductor or an insulator, depending on how it is treated. Silicon is the semiconductor material most commonly used in electronic components.
Transformer
A component that transforms an input alternating current (AC) voltage to either a higher level (step-up transformer) or a lower level (step-down transformer) AC voltage.
Transistor, BJT
A bipolar junction transistor (BJT) is a semiconductor component that can either be used as a switch or an amplifier. In either case, a small input signal controls the transistor, producing a much larger output signal.
Transistor, JFET
A junction field effect transistor (JFET), which, like the bipolar junction transistor, can be used either as a switch or an amplifier.
Transistor, MOSFET
Like the BJT and JFET, a metal oxide silicon field effect transistor (MOSFET) that can be used either as a switch or an amplifier. The MOSFET is the most commonly used transistor in integrated circuits.
Turns ratio (TR)
The ratio of the number of turns in the primary or input winding of a transformer to the number of turns in the secondary (or output) winding.
Volt (V)
The unit of measurement for the potential difference that causes a current to flow through a conductor.
Voltage (V)
The potential difference of energy that, when applied to an electrical circuit, causes current to flow, measured in volts.
Watt (W)
Unit of electric power dissipated as heat when 1 amp of curren
t flows through a component that has 1 volt applied across it.
Zener
A particular type of diode that enables the flow of current at a definite reverse-bias voltage level.
Appendix B
List of Symbols and Abbreviations
The following table lists common symbols and abbreviations.
Symbol/Abbreviation Meaning
A Ampere
AC Alternating current
App Peak-to-peak amperes
Arms Root mean square amperes
AV AC voltage gain
β (beta) Current gain
BW Bandwidth
C Capacitor
DC Direct current
F Farad
gm Transconductance
f Frequency
fr Resonant frequency
H Henry
Hz Hertz
I Electric current
IB Base current
IC Collector current
ID Drain current of a field effect transistor (FET); also current through a diode
IDSS Saturation current
Ipp Peak-to-peak current
Irms Root mean square current
kHz Kilohertz
k Kilohm
kW Kilowatt
L Inductor
LC Inductor-capacitor circuit
mA Milliampere
mH Millihenry
M Megohm
μA Microampere
μF Microfarad
μH Microhenry
μs Microsecond
ms Millisecond
mV Millivolt
Np Number of turns in a primary coil
NS Number of turns in a secondary coil
Ω Ohms
pF Picofarad
P Power
Q Transistor; also the Q value of a resonant circuit
R Resistor
Rin Input resistance of a transistor
r DC resistance of an inductor
T Period of a waveform
τ Time constant
TR Turns ratio
θ Phase angle
μV Microvolt
V Voltage
VC Voltage at the collector of a transistor
VDD Drain supply voltage
VE Voltage at the emitter of a transistor
VGG Gate supply voltage
VGS Gate to source voltage
VGS (off) Gate to source cutoff voltage
Vin AC voltage of an input signal
Vout AC output voltage
Vp Peak voltage
Vpp Peak-to-peak voltage
Vrms Root mean square voltage
VS Supply voltage
W Watts
XC Reactance of a capacitor
XL Reactance of an inductor
Z Impedance
Appendix C
Powers of Ten and Engineering Prefixes
The following table shows powers of the number 10, decimal equivalents, prefixes used to denote the value, symbols used, and typical usages.
Appendix D
Standard Composition Resistor Values
The most commonly used type of resistor is the carbon film resistor with a ± 5 percent tolerance and either a 1/4 or 1/2 watt power rating. The standard resistance values for this type of resistor are listed in the following table (in ohms). You should purchase resistors at any of these values through the online distributors listed in Appendix E, “Supplemental Resources.” Power resistors are available with fewer resistance values, which you can find in the catalogs of various suppliers.
Note In the following table, “k” represents kilo-ohms, so 7.5 k translates into 7,500 ohms. Similarly, “M” stands for megohms, so a value of 3.6 M represents 3,600,000 ohms.
Appendix E
Supplemental Resources
This appendix provides a list of websites, books, magazines, tutorials, and electronics suppliers that should be of interest if you want more knowledge about basic electronics concepts, reference material for circuit design, or the supplies needed to build circuits.
Web Sites
Following are some websites that may prove useful:
Building Gadgets (www.buildinggadgets.com/)—This is an electronics reference site maintained by Earl Boysen (one of the authors of this book). There are lots of handy links to electronics tutorials, discussion forums, suppliers, and interesting electronics projects here. This website includes support web pages for each project in the Complete Electronics Self-Teaching Guide, including the following: Data sheets for key components.
Parts lists with links to the appropriate locations in online catalogues for suppliers.
Color photos showing details of circuit construction and testing.
All About Circuits (www.allaboutcircuits.com/)—This site includes an online book on electronics theory and circuits, as well as discussion forums on electronics projects, microcontrollers, and general electronics issues.
Williamson Labs (www.williamson-labs.com/)—This site includes tutorials on electronics components and circuits. Many of these tutorials include animated illustrations that can help you understand how each circuit functions.
Electro Tech online (www.electro-tech-online.com/)—This is a discussion forum on electronics projects and general electronics issues.
Electronics Lab (www.electronics-lab.com/index.html)—This is a collection of a few hundred interesting electronics projects.
Discover Circuits (www.discovercircuits.com/)—This is a collection of thousands of electronic circuits.
Books
Following are some books that may prove useful:
Electronics For Dummies, Second Edition, by Cathleen Shamieh and Gordon McComb (Indianapolis: Wiley, 2009)—This is a good book to start with. It provides an introduction to electronics concepts, components, circuits, and methods.
The Art of Electronics, Second Edition, by Paul Horowitz and Winfield Hill (New York: Cambridge University Press, 1989)—This is a useful reference book for designing circuits, as well as understanding the functionality of existing circuits.
ARRL Handbook for Radio Communications 2012 (Newington, Connecticut: American Radio Relay League, 2012)—Although this is intended for ham radio enthusiasts, it is also a useful reference book for understanding circuit design. This handbook is updated every year, but if you buy the current edition, it should be good for several years.
Magazines
Following are some magazines that may prove useful:
Everyday Practical Electronics Magazine (www.epemag3.com/)—This magazine provides interesting detailed electronics projects for hobbyists.
Nuts and Volts Magazine (www.nutsvolts.com/)—This magazine provides information on new components for hobbyists and projects, focusing on circuits using microcontrollers.
EDN Magazine (www.edn.com/)—This magazine includes articles on new components/designs for the engineering community.
Suppliers
This section shows retail stores and online distributors.
Retail Stores
Following are some retail stores that may prove useful:
Radio Shack (www.radioshack.com/)—This retail chain carries electronic components and has stores in most U.S. cities.
Fry's Electronics (www.frys.com/)—This retail chain carries electronics components and has stores in nine states.
Online Distributors
Following are some online distributors that may prove useful:
Jameco Electronics (www.jameco.com/)—This is a medium-sized distributor that carries most of the components you'll need, with a reasonably sized catalog that you'll find easy to use to find components.
Mouser Electronics (www.mouser.com/)—This is a large distributor that carries a wide range of components with a nice ordering system on its website that lets you put together separate orders for different projects, which is handy if you're planning multiple projects. This distributor also does a good job of packaging, clearly labeling components for shipment.
Digi-key (www.digikey.com/)�
��This is another large distributor with a broad selection of components. Digi-key may carry components that are difficult to find at smaller suppliers.
Appendix F
Equation Reference
The following table provides a quick reference to common equations.
Appendix G
Schematic Symbols Used in This Book
The following table shows schematic symbols used in this book.
Component Symbol
Battery
Buzzer
Capacitors Capacitor
Variable Capacitor
Diodes Diode
Zener Diode
Light Emitting Diode
Photodiode
Generator (DC)
Ground
Inductors Inductor
Tapped Inductor
Lamp
Meters Meter
Ammeter
Voltmeter
Motor
Operational Amplifier
Resistors Resistor
Two-Contact Variable Resistor (Potentiometer)
Three-Contact Variable Resistor (Potentiometer)
Signal Generator (Sine Wave)
Switches Single-pole, Single-Throw (SPST) Switch
Single-pole, Double-Throw (SPDT) Switch
Test Point
Transformers Transformer
Center Tap Transformer
Transistors NPN BJT
PNP BJT
N-Channel JFET
P-Channel JFET
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