Download C7804 Electric Components newer

Parts
Identification
Electronic Training Course
Slide# 1
Parts Identification
Objective
The purpose of this electronic training course is
to learn how to identify components by name,
physical appearance, and schematic symbol.
Slide# 2
Parts Identification
Resistors oppose current flow. They are used in electronic circuits
to limit the amount of current that flows in the circuit. The figure
shows four common types of resistors: the carbon resistor, the
wire wound, the sandstone and the potentiometer. The carbon
resistor uses a color code to identify its value. The wire wound and
the sandstone resistors are also called power resistors, they can
handle large amounts of current and typically do not use the
resistor color code, instead they have their value printed on their
case.
Slide# 3
Parts Identification
The potentiometer is nothing more than a variable resistor. It has a
shaft that is used to adjust the value of resistance. Potentiometers
are used as volume controls in amplifiers and in hundreds of other
applications. Potentiometer values are typically marked
somewhere on the case.
Slide# 4
Parts Identification
Notice the schematic symbol of the resistors and the
potentiometer. Resistors do not have polarity and can be installed
in any direction in a circuit.
The resistance of a resistor is measured in ohms. Multiples are
commonly used to express resistor value.
K ohm (Kilo ohm: 1000 ohms)
M ohm (Mega ohm: 1,000,000)
Slide# 5
Parts Identification
Capacitors store electrical energy. They act as temporary batteries
holding up voltage until they are discharged. Capacitors are used in
hundreds of applications in electronic circuits.
The figure shows six different types of capacitors: disc, mylar and
variable capacitors which do not have polarity, and the radial, axial
and tantalum capacitors which do have polarity. Capacitors that
have polarity, must be installed with the correct orientation and
typically are marked with a “–” or “+” symbol for lead polarity
identification.
Slide# 6
Parts Identification
Notice the schematic symbol of the different types of capacitors.
The radial, axial, and tantalum capacitors schematic symbol shows
the polarity for correct physical installation.
The capacitance of a capacitor is measured in farads. The farad is
a very big unit and submultiples are commonly used.
uF/µF (micro farad: 10-6 )
nF (nano farad: 10-9)
pF (pico farad: 10-12)
Slide# 7
Parts Identification
Coils store electrical energy in a magnetic field created around
them. Coils are used in hundreds of applications in electronics and
especially in communication devices: transmitters, receivers, etc.
The figure shows a few of the many types of coils.
Wire coils and variable coils are used mainly in oscillator circuits of
transmitters and receivers to generate AC (alternating current)
signals.
Slide# 8
Parts Identification
Choke coils are mainly used in filter circuits to reject unwanted
signals. Trigger coils are used in strobe light circuits to produce a
very high voltage to trigger the flash tube.
Coils do not have polarity. The inductance of a coil is measured in
henries. The henry is a very high unit and submultiples are
commonly used.
uH/µH (micro henry: 10-6 )
mH (mili henry: 10-3
Slide# 9
Parts Identification
Transformers step up or down voltage. Transformers do not have
polarity but they have a primary and secondary coil that have to
be connected properly in the circuit. The figure shows three
common types of transformers.
Power transformers are used in electronic equipment that
connects to the wall socket. This reduces the 120VAC from the wall
outlet to a suitable voltage for the device.
Audio transformers are used in audio amplifiers, oscillators etc.
Slide# 10
Parts Identification
Radio frequency transformers are used in communication devices
such as receivers and transmitters.
Transformers are rated by the voltage or impedance of their coils
and the current and voltage they can handle. For example a power
transformer can be rated as: 120Volts to 12Volts/1 Amp. Meaning
that the primary receives the 120 Volts and the secondary will step
that voltage down to 12 volts with the capacity of delivering 1 Amp
of current. Audio transformers can be rated as: 1000 ohms to 8
ohms/10 watts.
Slide# 11
Parts Identification
Switches are used to open (interrupt) and close (connect) electric
or electronic circuits. Switches do not have polarity. Switches are
rated by the arrangement of their contacts (Single Pole/Single
Throw: SPST, Single Pole/Double Throw: SPDT, etc.) and the
maximum current and voltage their contacts can handle. Switches
are manufactured in many types and sizes and the figure shows
the most common types. The relay is a special electric switch that
closes or opens its contacts when voltage is applied to its coil.
Slide# 12
Parts Identification
Diodes are special semiconductive devices that allow current to
flow through them in one direction only. They behave like an
electronic “one way street”. Diodes have polarity. They have two
terminals known as the cathode (C) and the anode (A). The diode
allows current to flow through it only when the cathode is
negative and the anode is positive. The figure shows several types
of diodes in common use in electronic circuits. Power diodes are
used in power supplies and rectifier bridges to convert AC voltage
(alternating current like the one in the wall socket) into DC voltage
(direct current like battery current).
Slide# 13
Parts Identification
Zener diodes are used as voltage regulators and signal diodes
are used in communication and digital circuits.
LEDs (Light Emitting Diodes) are a special type of diodes that
emit light when current flows through them.
7-segment displays are a group of LEDs arranged in a
"figure 8” to display alphanumeric characters.
Slide# 14
Parts Identification
SCRs (Silicon Controlled Rectifiers) are diodes that only
conduct after a positive pulse has been applied to its gate
lead. Notice the schematic symbols of the different diodes.
Power diodes, zeners, bridge rectifiers and SCRs are rated by
the voltage and current they can handle. Signal diodes are
rated by type. LEDs and 7-segment displays are rated by their
size, color and type of lens.
Slide# 15
Parts Identification
Transistors amplify and switch current. They are very important
semiconductive devices that are found in almost any electronic
circuit today, either as an individual component or consolidated
into integrated circuits (ICs). Transistors have polarity. They have
three terminals called: emitter (E), base (B), and collector (C).
Transistors are basically classified according to their type (NPN or
PNP) and the power they can handle: small signal or power
transistors. NPN and PNP type transistors have different
schematic symbols.
Slide# 16
Parts Identification
Integrated Circuits (ICs) consolidate a large electronic circuit
containing transistors, resistors, diodes, capacitors, etc, into a
small package. ICs have polarity and have to be installed with the
notch, dot or band on the case in the correct orientation. There
are thousands of different types of ICs but basically they can be
classified into three large families: CMOS, TTL and Linear. Each
family has its own electrical characteristics.
Slide# 17
Parts Identification
Speakers transform electrical energy into sound. Speakers
have two terminals. They do not have polarity but they have
phase.
If you connect two speakers together, they will have to be “in
phase” in order to get maximum sound from them. The
phase of the speaker is indicated by a colored terminal and
sometimes by a positive or negative mark.
Slide# 18
Parts Identification
Speakers are rated by their impedance (resistance to the
alternating current) 4 ohms, 8 ohms, etc, and by the power
they can handle: 10 watts, 100 watts, etc.
The piezo element and the buzzer shown on the figure also
transform electrical energy into sound, but in contrast with
the speakers, the sound they produce have a fixed frequency
(tone).
Slide# 19
Parts Identification
Microphones transform sound into an electric signal.
Microphones may or may not have polarity depending on the
type.
The electret type microphone shown in the figure has
polarity, while the crystal and dynamic have no polarity.
Slide# 20
Parts Identification
CDS (Cadmium Sulfide) Cells, also commonly called
photocells, vary their internal resistance according to the
light they receive.
CDS cells do not have polarity. CDS cells are rated by their
resistance range (ohms).
CDS cells are manufactured in many forms and sizes.
Slide# 21
Parts Identification
Lamps transform electric energy into light. There are many types of
lamps used in electronics, as shown in the figure.
In an incandescent lamp the light is produced when the current
flows through a tiny filament that gets extremely hot.
In the neon, fluorescent and xenon types, the light is emitted when
an internal gas gets ionized.
Notice the differences in the schematic symbols of the different
types of lamps.
Slide# 22
Parts Identification
Test
Identify the Components
Slide# 23
Parts Identification
Test
Identify the Components
Resistor
Slide# 24
Parts Identification
Test
Identify the Components
Resistor
LED
Slide# 25
Parts Identification
Test
Identify the Components
Resistor
LED
Transistor
Slide# 26
Parts Identification
Test
Identify the Components
Resistor
LED
Transistor
Transformer
Slide# 27
Parts Identification
Test
Identify the Components
Resistor
LED
Transistor
Transformer
Lamp
Slide# 28
Parts Identification
Test
The figure shows the schematic symbol of a _____.
The figure shows the schematic symbol of a _____.
The figure shows the schematic symbol of a _____.
What is the function of a resistor?
What is the function of a capacitor?
Slide# 29
Parts Identification
Test
The figure shows the schematic symbol of a _____.
Capacitor
The figure shows the schematic symbol of a _____.
The figure shows the schematic symbol of a _____.
What is the function of a resistor?
What is the function of a capacitor?
Slide# 30
Parts Identification
Test
The figure shows the schematic symbol of a _____.
Capacitor
The figure shows the schematic symbol of a _____.
Resistor
The figure shows the schematic symbol of a _____.
What is the function of a resistor?
What is the function of a capacitor?
Slide# 31
Parts Identification
Test
The figure shows the schematic symbol of a _____.
Capacitor
The figure shows the schematic symbol of a _____.
Resistor
The figure shows the schematic symbol of a _____.
Switch
What is the function of a resistor?
What is the function of a capacitor?
Slide# 32
Parts Identification
Test
The figure shows the schematic symbol of a _____.
Capacitor
The figure shows the schematic symbol of a _____.
Resistor
The figure shows the schematic symbol of a _____.
Switch
What is the function of a resistor?
Oppose current flow
What is the function of a capacitor?
Slide# 33
Parts Identification
Test
The figure shows the schematic symbol of a _____.
Capacitor
The figure shows the schematic symbol of a _____.
Resistor
The figure shows the schematic symbol of a _____.
Switch
What is the function of a resistor?
Oppose current flow
What is the function of a capacitor?
Store electrical energy
Slide# 34