-\/\/\-  -)|-  -||-  -þ-  ->-  ->\-  |Û  -@-  ./.  >-  ._|_.  -³|-  ->[<-
_________________________________________________________________________
°°°°°°°°°°°°°°°°°°°°°"A Basic Course In Electronics"°°°°°°°°°°°°°°°°°°°°°
                     -------------------------------
This file is for all those folks who have ever wanted to know more
about electronics.

    Electronics is great, no matter what your reason for wanting to
learn it.  Maybe you want to learn how to build your own stereo system,
or want to be able to fix all the things you break, or perhaps you want
to 'improve' something., or maybe you just want to become a ham, but
don't know squat.
    I will attempt to explain the basics of electronics in this file, but
reading this alone will do nothing for you, it will probably just confuse
you.  
    You probably already know something about electronics.  But before I
get into the fun stuff like soldering and so on, I think you should know
the principals behind your work.

THE DREADED FORMULAS

  "What?  I have to use math?  Forget this..." if you just said that to
yourself after seeing "The Dreaded Formulas" I suggest that you learn
how to use a calculator, or everything you build is gonna be a piece of
schmeg.
   _________                    ³   _________                    ÚÄÄÄÄÄÄÄÄÄ¿
  /    E    \                   ³  /    P    \                   ³ T   I   ³
 ÃÄÄÄÄÄÂÄÄÄÄ-³                  ³ ÃÄÄÄÄÄÂÄÄÄÄÄ´                  ³ H   M   ³
 ³  I  ³  R  ³                  ³ ³  I  ³  E  ³                  ³ E   P   ³
  \____³____/                   ³  \____³____/                   ³ S   O   ³
                                ³                                ³ E   R   ³
E= Volts or Electricty          ³ P= Watts or Power              ³     T   ³
I= Amps or Current              ³ I= Amps or Current             ³ A   A   ³
R= Ohms or Resistance           ³ E= Volts or Electricity        ³ R   N   ³
                                ³                                ³ E   T   ³
              Voltage           ³           Watts                ³         ³
Current=     ÄÄÄÄÄÄÄÄÄÄ         ³ Current=  ÄÄÄÄÄ                ³ T   F   ³
             Resistance         ³           Volts                ³ H   O   ³
                                ³                                ³ E   R   ³
             Voltage            ³            Power               ³     M   ³
Resistance=  ÄÄÄÄÄÄÄ            ³ Voltage=  ÄÄÄÄÄÄÄÄ             ³ M   U   ³
             Current            ³           Current              ³ O   L   ³
                                ³                                ³ S   A   ³
Voltage=     Current*Resistance ³ Power=    Amps*Volts           ³ T   S   ³
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÙ
Definition
Voltage- The amount of electrical pressure
Current- The flow of electrons
Resistance- Opposition to the flow of electrons
Power- The rate of energy consumption
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
-=ðSERIES CIRCUITSð=-

Adding resistance:        Adding voltage:         Adding current:
Rt= R1+R2+R3+...          Et= E1+E2+E3+...        It= I1=I2=I3=...
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
                                PAGE 1
-=ðPARALLEL CIRCUITSð=-

Adding resistance:        Adding voltage:         Adding current:
    1   1    1    1       Et= E1= E2= E3=...      It= I1+I2+I3+...
Rt= Ä = ÄÄ + ÄÄ + ÄÄ +...
    R   R1   R2   R3
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
THE FOLLOWING MAY BE COMPLETELY BORING, BUT READ IT ANYWAY,  I
UNFORTUNATELY CAN NOT MAKE IT FUN, YOU NEED TO KNOW THIS STUFF!

RESISTORS
What is the definition of a resistance?  The ability of a material to
oppose the flow of electrons is called resistance.  All materials
exhibit a certain amount of resistance to electron flow.  In order to
compare the resistance of various materials, we require some standard
unit of measurement.  The unit of resistance that was adapted for this
purpose is the Ohm.  The Greek letter Omega ê (which looks like an
upside-down horse-shoe) is its symbol.  One ohm may be defined as the
amount of resistance inherent in 1,000 feet of #10 copper wire.  For
example, 5,000 feet of #10 copper wire  would have a resistance of 5
ohms; 10,000 feet of #10 copper wire would have 10 ohms ect.  Although
the ohm is the basic unit, the megaohm, meaning 1,000,000 ohms, is
frequently used.  The instrument used to measure resistance is the
ohmmeter.  There are four factors which determine the resistance of a
conductor.  They are:

(1) LENGTH.  The resistance of a conductor is directly proportional to
its length.  The longer the conductor, the greater the resistance.  The
electrons have to flow through more material in a longer conductor, and
therefore meet more opposition.
(2) CROSS-SECTIONAL AREA.  The resistance of a conductor is inversely
proportional to the cross-sectional area.  This means that the
resistance becomes smaller as the thickness or area becomes larger.
(3) TEMPERATURE.  In practically all conductors, with the exception  of
carbon, the resistance varies directly with the temperature.  As the
temperature of a conductor rises, its resistance increases; as the
temperature drops, the resistance decreases.
(4) MATERIAL MAKE-UP.  The resistance of a conductor depends upon the
material of which it is made.  Because of their material structure,
some conductors have more resistance than others.

-Resistors are important components in electronic circuits.  A resistor
opposes the flow of electrons.  We can control the electron flow (the
current) by varying the resistance in a circuit.  Most resistors have
standard fixed values, so they can be called fixed resistors.  Variable
resistors, also called pontentiometers, allow us to change the value of
the resistance without removing and changing the component.
-Potentiometers are used as the volume and tone controls in most stereo
amplifiers.  Resistors as said before come in different values.  Since
it is not always practical to print the resistance value on the side of
a small resistor, there is the resistor color code.  Reading a resistor,
band A [the one closest to the end of the resistor] represents the first
figure of the value.  Band B represents the second figure.  Band C
represents the number of zeros after the first two numbers.  Band D
indicates the tolerance [the guaranteed percentage of accuracy of the
color coded value].
                                PAGE 2

ÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
COLOR CODES: ³  Tolerance:      ³
Black  0     ³  Silver  10%     ³  RESISTOR COLOR CODES
Brown  1     ³  Gold    5%      ³
Red    2     ³  No 4th band 20% ³
Orange 3     ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Yellow 4     ³  Example:           Red =2  1st Digit
Green  5     ³       ÚRed        Green =5  2nd Digit
Blue   6     ³ _ÚÒÄÒÄÒÄÒÄÄ¿_       Red =2  No. Of Zeros
Violet 7     ³  ÀÐÄÐÄÐÄÐÄÄÙ     Silver =10% Tolerance
Gray   8     ³Red^ ³   ÀSilver
White  9     ³  Green            ANSWER: 2500 Ohms
ÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

SWITCHES
Single-Pole-Single-Throw [SPST]  Connects a single pair of wires, and
                                 has only two positions
Single-Pole-Double-Throw [SPDT]  Connects a single wire to one of two
                                 other contacts
Double-Pole-Single-Throw [DPST]  Connects two input lines to their
                                 respective output lines at the same time
Double-Pole-Double-Throw [DPDT]  Has two center contacts which connects
                                 these two center contacts to one of two
                                 other contacts

VOLTAGE AND CURRENT
Voltage is another term used to describe the difference of potential of
electrical pressure.  It is the force which pushes or forces electrons
through a wire.  The unit of voltage is the volt, and the instrument
used to measure it the voltmeter.  The kilovolt is equal to 1000 volts.
Current is the term commonly used to describe the flow of electrons.  It
is the result of the application of a difference of potential to a
circuit.  If we increase the number of electrons flowing past a point in
a given amount of time, we have more current.  The unit of current is
the ampere.  Milliampere and microampere are terms used to denote
one-thousandth and one-millionth of an ampere respectively.  Current is
measured with an ammeter.  Another term used in electrical work is the
coulomb.  The coulomb is the unit of electrical quantity.  The coulomb
is the number of electrons contained in one ampere.

FUSES
A fuse is simply a device made of metal that will heat up and melt,
creating an open circuit to protect your equipment when a certain
amount of current flows though it.  To protect against unexpected short
circuits and other problems.  A fuse in a transistor radio using little
power may be designed at 500 mA.  The fuses in your home's 120-V
circuits may be designed to blow at 15 or 20 A.  Remember that fuses
are designed to protect against too much current, not to much voltage.

BATTERIES
Batteries are made up of cells.  The cells produce a small voltage.  The
number of cells in a battery determines the voltage we get out of the
battery.  Electricity is created when a chemical reaction takes place
within the battery, this form of energy is called direct current [DC]
because the electrons move from the positive pole to the negative
pole.
                                PAGE 3


TRANSISTORS
Diodes and transistors are two types of semiconductors that have
replaces vacuum tubes.  These semiconductors are much smaller and
produce much less heat.  They are also usually less expensive than
tubes.  The most common type of transistor is the bipolar transistor.
Bipolar transistors are made of two different kinds of material.  The
two kinds of semiconductor material are known as N-type material and
P-type material.  The N refers to the way electrons, or negative
electric charges, move through the material.  The P refers to the way
positive charges move through the material.

Types Of Transistors
NPN transistor- A transistor that has a layer of P-type semiconductor
material sandwiched between layers of N-type semiconductor material.
PNP transistor- A transistor that has a layer of N-type semiconductor
material sandwiched between layers of P-type semiconductor material.

CAPACITORS
A capacitor is composed of two or more conductive plates with an
insulating material between them.  What is created is an electric field
between these plates.  A capacitor stores electric charge in the form of
of an electrostatic field.

DIRECT CURRENT [DC] & ALTERNATING CURRENT [AC]
Direct current is current that flows only in one direction.  Alternating
current is current that is constantly switching direction of flow.  It is
important to remember that current will only flow through a complete
circuit.
ÚÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
³SCHEMATICS³                                                                ³
ÃÄÄÄÄÄÄÄÄÄÄÙ                                                                ³
³Every circuit component has a schematic symbol.  A schematic symbol is     ³
³nothing more than a drawing used to represent a component.  We use these   ³
³symbols when we are making a circuit diagram, or wiring diagram, to        ³
³show how the components connect for a specific purpose.                    ³
³                                                                           ³
³At this point I would like to point out that the following schematic       ³
³symbols are going to look distorted, since this is a text file it's near   ³
³impossible to replicate the true schematic symbol for each component.      ³
³                                                                           ³
³In this file:                -      +                                      ³
³A battery is       -|³-      -|³|³|³-  [Of coarse we should know that + is ³
³shown as        Single Cell Multi-cell  positive & - means negative]       ³
³                                                                           ³
³A resistor is shown as -\/\/\/\-                                           ³
ÆÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ͵
³Complete Circuit                                                           ³
³         ÚÄÄÄÄÄÄÄÄÄ¿       Another Way to show this: ÚÄÄÄÄÄÄÄÄÄ¿           ³
³       + ³         /                                 ³         ³           ³
³Source  ÄÁ-        \ Load       S1=Source          S1*         *R1         ³
³       - Â         /            R1=Resistor          ³         ³           ³
³         ÀÄÄÄÄÄÄÄÄÄÙ                                 ÀÄÄÄÄÄÄÄÄÄÙ           ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ
                                Page 4




SERIES CIRCUIT
ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
³Find the resistance of R2    | Solution: Since we know the total current & ³
³        R1         R2=?      | battery voltage, we can use Ohm's law to    ³
³ÚÄÄÄÄÄ/\/\/\ÄÄÄÄÄÄ/\/\/\ÄÄÄ¿ | find total resistance.                      ³
³³ .5 A                     ³ |     E   100       Since the total resistance³
³ÀÄÄÄAÄÄÄÄÄÄÄ|³|³ÄÄÄÄÄÄÄÄÄÄÄÙ | Rt= Ä = ÄÄÄ = 200 in this series circuit is ³
³R1= 75 ê        100 V        |     I   .5        200 ohms and R1= 75 then  ³
³ANSWER:                      |                   R2= Rt - R1               ³
³R2= 125 ê                    | R2= 200 - 75 = 125 ohms                     ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ
PARALLEL CIRCUIT
ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
³Find the current through R2  |Solution: Since we know the resistance of R1 ³
³Find the total current       |and the current through R1, we can find the  ³
³       R1                    |voltage across R1 using Ohm's law.           ³
³ ÚÄÄÄ/\/\/\ÄÄ¿               |E   I       E           E                    ³
³ ³     R2    ³               | R1= R1*R1   R1= .2*50   R1= 10 V            ³
³ ÃÄÄÄ/\/\/\ÄÄ´               |Since R1 is in parallel with R2, the voltage ³
³ ³           ³               |across R2 is the same as that across R1.     ³
³ ÀÄÄÄ|³|³ÄÄÄÄÙ               |Therefore, E                                 ³
³R1= 50 ê                     |            R2= 10 V                         ³
³R2= 200 ê                    |Knowing the resistance of R2 and the voltage ³
³Current through R1 is .2 A   |across it, we can find the current through R2³
³                             |I   ER2   10                                 ³
³ANSWER:                      | R2=ÄÄÄ = ÄÄÄ = .05 Amp                      ³
³R2= .05 Amp                  |     R2   200                                ³
³Total Current= .25 Amp       |In a parallel circuit, the total current is  ³
³                             |equal to the sum of the induvidual branch    ³
³                             |currents; therefore:                         ³
³                             |I = I   + I     / I = .2 A + .05 A = .25 Amp ³
³                             | T   R1    R2  /   T                         ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ
I just finished describing series & parallel circuits.  I bet that you
are royaly confused right now.  That is why I will skip combination
circuits.  These types of circuits are both series and parallel.  They
are near impossible to describe.  If you know series and parallel really
good there is no need to talk about combination circuits.  I also gave
you a brief description of some common components.  If what you've seen
looks retarded, maybe your not cut of for this sort of thing.  I don't
want you to waste your time so move on, try some other hobby.

Other miscellaneous info
-=-=-=-=-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
þIn a conductor, the free electrons are tightly bond to their atoms.
þThe unit of electrical quantify is the coulomb.
þA voltmeter measures electrical pressure.
þResistance is measured by an ohmmeter.
þThe unit of electrical current is the ampere.
þA kilovolt is 1000 volts.
þThe instrument used to measure power is the wattmeter.
þOhm's law states that the resistance is equal to the voltage divided by
 the current.
þThe ratio of current to voltage in a circuit is know as conductance.
þThe resistance of two equal resistors connected in parallel is one-half
 of one of the resistors.
þIn a series circuit, the source voltage is equal to the total
 resistance multiplied by the total current.
þThe total current in a series circuit is equal to the current in any
 part of the circuit.
þA short circuit causes a heavy current to be drained from the
 electrical source.
þWhen soldering, the work should be heated, rather than the solder.
/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
Stay tunned for part II, "Soldering"...