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PC Electronics Plus (Most Significant Bits)(1995).ISO
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elec6.cai
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1991-12-20
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@OPTIONS ESCAPE NOEDIT
@ESC SYSTEM
.SCREEN 0
.COLOR 15,0
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ INTRODUCTION ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
.LOCATE 9,14
All electrical and electronic products are built from
.LOCATE 10,14
a limited number of basic components that perform
.LOCATE 11,14
one of two functions:
.LOCATE 13,14
1. Switch the flow of current on and off.
.LOCATE 15,14
2. Regulate the amount of current that flows through
.LOCATE 16,17
all or part of the circuit.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
.LOCATE 7,16
That's correct, the only thing the components in an
.LOCATE 8,16
a circuit can do is:
.LOCATE 11,26
SWITCH THE CURRENT ON AND OFF
.LOCATE 13,40
or
.LOCATE 15,17
REGULATE (INCREASE/DECREASE) THE AMOUNT THAT FLOWS
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ COMPONENTS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
.LOCATE 10,13
To perform the kind of complex tasks we associate with
.LOCATE 11,13
electrical and electronic products using components
.LOCATE 12,13
that are so limited in what they can do, engineers use
.LOCATE 13,13
those simple components as building blocks.
.LOCATE 15,13
Separate circuits are constructed using various components
.LOCATE 16,13
and then different circuits are linked together to make
.LOCATE 17,13
a complete system.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ COMPONENTS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
.LOCATE 5,22
The most commonly used components are:
.LOCATE 7,36
RESISTORS
.LOCATE 8,36
CAPACITORS
.LOCATE 9,37
DIODES
.LOCATE 10,35
TRANSISTORS
.LOCATE 12,22
In electronic products those components
.LOCATE 13,22
can be mounted on:
.LOCATE 15,30
PRINTED CIRCUIT BOARDS
.LOCATE 17,39
or
.LOCATE 19,22
Miniaturized and placed on silicon wafers
.LOCATE 20,22
in the form of:
.LOCATE 22,31
INTEGRATED CIRCUITS
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ RESISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
.LOCATE 7,16
In Section Two we discussed the measurement of the
.LOCATE 8,16
of the activity in a circuit in terms of:
.LOCATE 10,21
VOLTS - The "pressure" of the electrons.
.LOCATE 12,15
AMPS - The volume of electrons flowing in a circuit.
.LOCATE 14,13
WATTS - The total amount of power (WATTS = VOLTS x AMPS)
.LOCATE 16,39
and
.LOCATE 18,10
OHMS - The measure of the RESISTANCE to the flow of electrons.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ RESISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
The RESISTOR is the component used to:
REDUCE THE AMOUNT OF POWER FLOWING IN PART OF THE CIRCUIT
When a Resistor is inserted in a circuit, some of the energy
of the flowing electrons will be dissipated in the form of
heat at that location. In a Blower Motor, Resistors are used
to vary the amount of power going to the motor, which makes
the motor run faster or slower as desired.
┌─────────────────────────┐
│ Symbol: --/\/\/\/\/\-- │
│ │
│ or │
│ │
│ __┌────────┐__ │
│ └────────┘ │
└─────────────────────────┘
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ RESISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
VARIABLE RESISTORS
A Variable Resistor is one in which the amount of power
or voltage being absorbed can be adjusted. A radio volume
control is an excellent example of a Variable Resistor.
A Variable Resistor is also known as a POTENTIOMETER.
┌─────────────────────────┐
│ Symbol: │
│ --/\/\│\/\/\-- │
│ │ │
│ │
│ or │
│ │
│ │ │
│ __┌───────┐__ │
│ └────────┘ │
└─────────────────────────┘
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ RESISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
.LOCATE 9,13
While the Resistors used in Blower Motors are typically
.LOCATE 10,13
coils of wire mounted on a "Resistor Block", most
.LOCATE 11,13
Resistors used in electrical and electronic circuits
.LOCATE 12,13
are made from carbon or other material encased in
.LOCATE 13,13
a ceramic sleeve.
.LOCATE 15,13
Such resistors are easy to identify thanks to the
.LOCATE 16,13
distinctive color coded rings on the sleeve used to
.LOCATE 17,13
indicate the resistance value and other specifications.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ RESISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
TYPICAL RESISTOR
┌─┬─┬──┬─┬──┬─┬──┬─┬───┐
════════╡ │░│ │▒│ │▓│ │█│ ├════════
└─┴─┴──┴─┴──┴─┴──┴─┴───┘
First Digit ──┘ │ │ │
Second Digit ──────┘ │ │
Multiplier ─────────────┘ │
Tolerance ───────────────────┘
First Digit = First digit of resistance value (0 thru 9) in OHMS
Second Digit = Second Digit of resistance value (0 thru 9) in OHMS
Multiplier = Number of zeros after first two numbers
Tolerance = "Margin for error" - more or less than above numbers
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ RESISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
CALCULATING A RESISTOR VALUE BASED ON THE FOLLOWING STANDARD COLOR CODES:
COLOR DIGIT ZEROS COLOR DIGIT ZEROS
Black = 0 None Green = 5 5
Brown = 1 1 Blue = 6 6
Red = 2 2 Violet = 7 7
Orange = 3 3 Grey = 8 8
Yellow = 4 4 White = 9 9
┌─┬─┬──┬─┬──┬─┬──┬─┬───┐
════════╡ │░│ │▒│ │▓│ │█│ ├════════
└─┴─┴──┴─┴──┴─┴──┴─┴───┘
Brown ────────┘ │ │ │
Blue ──────────────┘ │ │
Orange ─────────────────┘ │
Tolerance ───────────────────┘
┌───────────────────────────────────────────────────────────────────────┐
│1st RING:BROWN(1) 2nd RING:BLUE(6) 3rd RING:ORANGE(000) = 16,000 OHMS│
└───────────────────────────────────────────────────────────────────────┘
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ CAPACITORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
While a Resistor's role is to reduce the amount of power
flowing to part of a circuit, a CAPACITOR performs just the
opposite function - it collects electric current and allows
it to build up to a higher level.
One location where a Capacitor (Condenser) is used in automotive
applications is in the ignition circuit between the coil and
the points. It collects any primary current that flows when
the points are opening to prevent the current from arcing
between the contacts.
┌─────────────────────────┐
│ Symbol: │
│ │
│ │ │ │
│ ──────┤ ├────── │
│ │ │ │
│ │
└─────────────────────────┘
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
.LOCATE 10,17
A dramatic example of a CAPACITOR at work
.LOCATE 11,17
occurs in the kind of electronic flash unit used on
.LOCATE 12,17
most 35 mm cameras. The capacitor absorbs energy
.LOCATE 13,17
from the small batteries and then releases it
.LOCATE 14,17
to provide the burst of power required to create
.LOCATE 15,17
a flash of bright light.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ DIODES ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
A DIODE is a valve that allows electric current
to flow only in one direction in a circuit.
It can be useful in preventing current in one wire
from "spilling over" into another and from flowing
"backwards" in a circuit.
Diodes are also used to convert ALTERNATING CURRENT
into DIRECT CURRENT (Remember, the flow of Electrons
keeps reversing in Alternating Current). Diodes are
used in products like battery chargers where they are
called RECTIFIERS.
┌─────────────────────────┐
│ Symbol: │
│ │ /│ │
│ ──────┤─├───── │
│ │ \│ │
│ │
└─────────────────────────┘
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌──────┐
┌──────────────────────────────────│REVIEW│──────────────────────────────────┐
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒└──────┘▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒┌──────────────────────────────────┐▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒│REMEMBER THE FOLLOWING KEY POINTS:│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒└──────────────────────────────────┘▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒┌────────────────────────────────────────────────────────────────────────┐▒│
│▒│ │▒│
│▒│ │▒│
│▒│ │▒│
│▒│ │▒│
│▒│ │▒│
│▒└────────────────────────────────────────────────────────────────────────┘▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
└────────────────────────────────────────────────────────────────────────────┘
.WAIT 20
.LOCATE 12,5
1. RESISTORS REDUCE THE AMOUNT OF CURRENT FLOWING IN A CIRCUIT.
.WAIT 30
.LOCATE 14,5
2. CAPACITORS COLLECT CURRENT AND ALLOW IT TO BUILD UP.
.WAIT 30
.LOCATE 16,5
3. DIODES ARE VALVES THAT ONLY ALLOW CURRENT TO FLOW IN ONE DIRECTION.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ TRANSISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
The TRANSISTOR is the most versatile of the components
that can be included in a circuit. It is also the most
complicated.
A Transistor can be used as a SWITCH, to REGULATE the
flow of current, or even as a DIODE, depending on its
construction and how it is wired into the circuit.
┌─────────────────────────┐
│ Symbol: \ │
│(Non \ │
│ specific ├────── │
│ symbol) / │
│ / OR │
│ ────┤\ │
│(Amplifier │ \_____ │
│ Transistor) │ / │
│ ────┤/ │
└─────────────────────────┘
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ TRANSISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
.LOCATE 7,11
Remember from earlier sections that.......Electric Current
.LOCATE 8,11
is the flow of Electrons from a location where there is
.LOCATE 9,11
a supply of Free Electrons......to a location where there
.LOCATE 10,11
is a supply of atoms that have a shortage of Electrons.
.LOCATE 12,11
The location with the supply of Free Electrons is the - (minus)
.LOCATE 13,11
or Negative side of the circuit. When discussing Transistors
.LOCATE 14,11
this side is identified by the letter "N".
.LOCATE 16,11
The location with the supply of atoms that have a shortage
.LOCATE 17,11
of Electrons is the + (plus) side. It is identified by the
.LOCATE 18,11
letter "P".
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ TRANSISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
Unlike Resistors, Capacitors, and Diodes, which have only two
"leads" - a short wire at each end that allows the component
to be inserted into the circuit, a Transistor has THREE "leads".
--/\/\/\/\/\--
RESISTOR \
\
\
│ │ \
──────┤ ├────── │
│ │ ├──────────
CAPACITOR │
/
/
│ /│ /
──────┤─├───── /
│ \│
DIODE TRANSISTOR
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ TRANSISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
Transistors are made from SEMICONDUCTOR materials - solid
materials that can be a source of Free Electrons (N) or
atoms with a shortage of Electrons (P).
Two of the three "leads" in the Transistor attach to
parts of the Transistor that contain either "P" Semiconductor
material or "N" material.
The third "lead" attaches to a "BASE" that separates
the other two parts of the Transistor.
There are two possibilities:
│ │
┌──┬─┴─┬──┐ ┌──┬─┴─┬──┐
────┤P │ N │ P├──── ────┤N │ P │ N├────
└──┴───┴──┘ └──┴───┴──┘
As a result, there are PNP Transistors and NPN Transistors.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ TRANSISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
The way a Transistor works is easy to understand if you
think of the component two slices of "SEMICONDUCTOR"
material that have the same characteristics, separated
by a layer of material that is exactly the opposite - but
can change when Electrons are added to it or are withdrawn
from it.
When the middle material is opposite there is a "break"
in the circuit and current will not flow. If the status
of the middle material changes, the circuit will be
completed, and current will flow.
AND, since a Transistor has three "Leads" Electrons can
flow into or out of the Transistor from two separate
locations.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ TRANSISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
The following example illustrates how a Transistor can be
used as a SWITCH to activate a buzzer. In this case there
is a low power "Control" circuit that connects to a circuit
which contains a separate power source which will provide
the large amount of current required by the buzzer.
+│ - - │+
┌─┤├────────/\/\/\/\─────────────┬──────────┤├────────────────────┐
│ │ ┌┴┐ │ │
│ │N│ │
│ / ├─┤ ┌────┴───┐
└────■/ ■─/\/\/\/\─────────────┤P│ Electron │ BUZZER │
Electron flow ├─┤ Flow └────┬───┘
│N│ │
└┬┘ │
└────────────────────────────────┘
HOW IT WORKS: When the switch is open, the Base (P) acts as a barrier
to the flow of Electrons in the buzzer circuit which is served by its
own power supply. When the switch is closed, Electrons are pumped out
of the Base which allow electrons from the buzzer circuit to flow
across the base, completing the buzzer circuit.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ TRANSISTORS ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
A Transistor's ability to regulate the flow of current
is frequently used to increase the flow of current - by
combining current from two sources (or by creating two
paths from a single source) that feed into a common
point. In such applications the term AMPLIFIER TRANSISTOR
is used.
┌───────────────
┌┴┐ OUTPUT
│N│
Electron Flow├─┤
─────────────┤P│
INPUT ├─┤
│N│
└┬┘ Electron Flow
└───────────────
INPUT
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒ PRINTED CIRCUIT BOARDS AND INTEGRATED CIRCUITS ▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
In an Electrical Circuit, a path for Electrons to follow
is typically constructed from separate wires (and the
bodywork in the case of a vehicle) linked together, with
various components inserted in the wires, to form a loop.
A PRINTED CIRCUIT BOARD creates the same path in the form
of a pattern of conducting material deposited on a flat
board. The different components are then inserted into
the path. The "leads" from the components can be inserted
into holes in the paths and soldered, or they are soldered
on the paths without using holes (surface mount).
An INTEGRATED CIRCUIT is simply a miniaturized version of
a printed circuit that is built up in layers of different
materials to create paths for the current to follow as well
as components (resistors, diodes, and transistors) that
control the flow of current.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌──────┐
┌──────────────────────────────────│REVIEW│──────────────────────────────────┐
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒└──────┘▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒┌──────────────────────────────────┐▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒│REMEMBER THE FOLLOWING KEY POINTS:│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒└──────────────────────────────────┘▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
│▒▒▒▒▒┌───────────────────────────────────────────────────────────────┐▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒│ │▒▒▒▒▒▒│
│▒▒▒▒▒└───────────────────────────────────────────────────────────────┘▒▒▒▒▒▒│
│▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒│
└────────────────────────────────────────────────────────────────────────────┘
.WAIT 20
.LOCATE 9,12
1. THE FOUR BASIC ELECTRONIC COMPONENTS ARE: RESISTORS
.LOCATE 10,59
CAPACITORS
.LOCATE 11,59
DIODES
.LOCATE 12,59
TRANSISTORS
.WAIT 30
.LOCATE 14,12
2. THEIR ONLY FUNCTIONS ARE TO SWITCH (TURN OFF/ON) THE
.LOCATE 15,16
FLOW OF CURRENT OR REGULATE (INCREASE/DECREASE) IT.
.WAIT 30
.LOCATE 17,12
3. AN ELECTRONIC CIRCUIT IS JUST LIKE ANY OTHER
.LOCATE 18,16
ELECTRICAL CIRCUIT EXCEPT THAT IT IS SMALLER AND IT
.LOCATE 19,16
USES "SOLID STATE" COMPONENTS MADE OF SPECIAL
.LOCATE 20,16
SEMICONDUCTOR MATERIALS.
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
┌────────────────────────────────────────────────────────────────────────────┐
│ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ A FINAL NOTE ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
└────────────────────────────────────────────────────────────────────────────┘
We noted at the start of Section 1 that this INTRODUCTION
TO ELECTRICITY AND ELECTRONICS would not make you an
Electronics engineer. And even though we've just scratched
the surface, we have already covered a great deal of material
that should make it easier for you to understand any type
of electrical or electronic system. Some of the things you
should now know more about include:
ELECTRICITY AMPS CIRCUIT DIAGRAMS
ELECTRONICS WATTS LOADS
ELECTRONIC OHMS ELECTRICAL COMPONENT SYMBOLS
ELECTRONS MILLI (1/1000) ELECTRONIC COMPONENT SYMBOLS
FREE ELECTRON MICRO (1,1000,000) RESISTANCE/RESISTORS
DIRECT CURRENT TEST LIGHTS CAPACITORS
ALTERNATING CURRENT VOLTMETERS DIODES
CONVENTIONAL CURRENT OHMMETERS TRANSISTORS
ELECTRON CURRENT AMMETERS PRINTED CIRCUIT BOARDS
VOLTS CIRCUIT INTEGRATED CIRCUITS
.LOCATE 25,19
.PAUSE (*(Press ENTER to continue/ESCAPE to exit)*)
.CLS
.USE PROG=EQIZ6.CAI
