The document outlines a workshop practice focused on electronics, including objectives that teach students to read drawings, sketch jobs, and use soldering tools. It describes the symbols and conventions for various electronic components, such as switches, resistors, capacitors, and power supply symbols. Additionally, it details the soldering process, emphasizing the importance of safety and correct techniques for creating valid solder joints.

1. Basic Workshop Practice (Electronics
Group)
17005
DEPARTMENT OF ELECTRONICS ENGINEERING.

2. Objective
The student will be able to:
• Read and interpret the drawing.
• Draw sketch for given job.
• Use specification tables.
• Decide Sequence of procedure.
• Recognize, identify and use of various tools used in
soldering.
• Use of soldering technique for efficient repair work.
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3. Teaching & Examination Scheme:
Teaching Scheme Examination Scheme
TH TU PR
PAPER
HRS
TH PR OR TW TOTAL
-- -- 4 -- -- -- -- 50@ 50
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4. IDENTIFICATION OF ELECTRONIC COMPONENTS
ASSIGNMENT NO.01
• Drawing of symbols / conventions of
components, devices, electromechanical
switches, relays, Displays, connectors and cables
used in Electronics and Electrical engineering.
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5. Symbols / conventions of Wire
Sr.No. Symbol Component name Meaning
01
Electrical Wire Conductor of
electrical current
02
Connected Wires Connected
crossing
03
Not Connected
Wires
Wires are not
connected
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6. 2/6/2015 WPX ( 17005) 6
Switches
Power
Supply
Bulb

7. 2/6/2015 WPX ( 17005) 7
Switches
Power
Supply
Bulb

8. 2/6/2015 WPX ( 17005) 8
Switches
Power
Supply
Bulb

9. 2/6/2015 WPX ( 17005) 9
Switches
Power
Supply
Bulb

10. 2/6/2015 WPX ( 17005) 10
Switches
Power
Supply
Bulb

11. 2/6/2015 WPX ( 17005) 11
Switches
Power
Supply
Bulb

12. 2/6/2015 WPX ( 17005) 12
Switches
Power
Supply
Bulb

13. 2/6/2015 WPX ( 17005) 13
Switches
Power
Supply
Bulb

14. 2/6/2015 WPX ( 17005) 14
Switches
Power
Supply
Bulb

15. Symbols / conventions of Switches
Sr.No. Symbol Component name Meaning
01
SPST Toggle Switch
..SwitchesSPST.jpg
Disconnects
current when
open
02
SPDT Toggle Switch
..SwitchesSPDT.jpg
Selects between
two connections
03
Pushbutton Switch
(N.O)
Momentary switch
- normally open
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16. Symbols / conventions of Switches
Sr.No. Symbol Component name Meaning
04
Pushbutton Switch
(N.C)
..SwitchesPushbutton Switch
(N.O).jpg
Momentary switch
- normally Closed
05
DIP Switch
..SwitchesDIP.jpg
DIP switch is used
for onboard
configuration
06
SPST Relay Relay open / close
connection by an
electromagnet
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ON
OFF

17. Symbols / conventions of Switches
Sr.No. Symbol Component name Meaning
07
SPDT Relay
..SwitchesRelay.jpg
Relay open / close
connection by an
electromagnet
08
Jumper Close connection
by jumper
insertion on pins.
09
Solder Bridge Solder to close
connection
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18. Symbols / conventions of Ground
Sr.No. Symbol Component name Meaning
01
Earth Ground Used for zero
potential reference
and electrical
shock protection.
02
Chassis Ground Connected to the
chassis of the
circuit
03
Digital / Common
Ground
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19. Symbols / conventions of Resistor
Sr.No. Symbol Component name Meaning
01
Resistor (IEEE) Resistor reduces
the current flow.
02
Resistor (IEC)
..Switchesresistor-color-code-
all.gif
03
Potentiometer
(IEEE)
Adjustable resistor
- has 3 terminals.
04
Potentiometer (IEC)
..SwitchesPotentiometer.jpg
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20. Symbols / conventions of Resistor
Sr.No. Symbol Component name Meaning
05
Rheostat (IEEE) Adjustable resistor
- has 2 terminals.
06
Rheostat (IEC)
..SwitchesRheostat .jpg
07 Trimmer Resistor
..SwitchesTrimmer Resistor.jpg
Preset resistor
08
Thermistor
..SwitchesThermistor.jpg
Thermal resistor -
change resistance
when temperature
changes
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21. Symbols / conventions of Resistor
Sr.No. Symbol Component name Meaning
09
Photo resistor /
Light dependent
resistor (LDR)
..SwitchesLDR 1.jpg
Photo-resistor -
change resistance
with light intensity
change
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22. Symbols / conventions of Capacitor
Sr.No. Symbol Component name Meaning
01
Capacitor Capacitor is used to
store electric charge. It
acts as short circuit
with AC and open
circuit with DC.02
Capacitor
03
Polarized Capacitor Electrolytic capacitor
04
Polarized Capacitor
05
Variable Capacitor
..SwitchesCapacitor.JPG
Adjustable capacitance
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23. Symbols / conventions of Inductor
Sr.No. Symbol Component name Meaning
01
Inductor Coil / solenoid that
generates
magnetic field
02
Iron Core Inductor Includes iron
03
Variable Inductor
..SwitchesInductors.gif
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24. Symbols / conventions of Power Supply
Sr.No. Symbol Component name Meaning
01
Voltage Source Generates
constant voltage
02
AC Voltage Source AC voltage source
03
Current Source Generates
constant current
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25. Symbols / conventions of Power Supply
Sr.No. Symbol Component name Meaning
04
Generator Electrical voltage is
generated by
mechanical rotation of
the generator
05
Battery Cell Generates constant
voltage
06
Controlled Voltage
Source
Generates voltage as a
function of voltage or
current of other circuit
element.
07
Controlled Current
Source
Generates current as a
function of voltage or
current of other circuit
element.2/6/2015 WPX ( 17005) 25

26. Symbols / conventions of Meter
Sr.No. Symbol Component name Meaning
01
Voltmeter
..SwitchesVoltmeter.jpg
Measures voltage. Has
very high resistance.
Connected in parallel
02
Ammeter
..SwitchesAmmeter.jpg
Measures electric
current. Has near zero
resistance.
Connected serially.
03
Ohmmeter
..SwitchesOhmmeter.jpg
Measures resistance
04
Wattmeter
..SwitchesWattmeter.jpg
Measures electric
power
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27. Symbols / conventions of Lamp / Light Bulb
Sr.No. Symbol Component name Meaning
01
Lamp / light bulb
Generates light
when current
flows through
02
03
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28. Symbols / conventions of Diode
Sr.No. Symbol Component name Meaning
01
Diode Diode allows current
flow in one direction
only (left to right).
02
Zener Diode Allows current flow in
one direction, but also
can flow in the reverse
direction when above
breakdown voltage
03
Schottky Diode Schottky diode is a
diode with low voltage
drop
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29. Symbols / conventions of Diode
Sr.No. Symbol Component name Meaning
04
Varactor / Varicap
Diode
Variable capacitance
diode
05
Tunnel Diode
06
Light Emitting Diode
(LED)
LED emits light when
current flows
through
07
Photodiode
..SwitchesDiode.gif
Photodiode allows
current flow when
exposed to light
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30. Symbols / conventions of Transistor
Sr.No. Symbol Component name Meaning
01
NPN Bipolar Transistor Allows current flow
when high potential
at base (middle)
02 PNP Bipolar Transistor
Allows current flow
when low potential
at base (middle)
03
Darlington Transistor Made from 2 bipolar
transistors. Has total
gain of the product
of each gain.
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31. Symbols / conventions of Transistor
Sr.No. Symbol Component name Meaning
04
JFET-N Transistor N-channel field
effect transistor
05 JFET-P Transistor
P-channel field
effect transistor
06
NMOS Transistor N-channel MOSFET
transistor
07
PMOS Transistor
..Switchestransistorpinouts.gif
P-channel MOSFET
transistor
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WPX ( 17005) 31

32. Symbols / conventions of Antenna
Sr.No. Symbol Component name Meaning
01
Antenna / aerial
..SwitchesAntenna.jpg
Transmits & receives
radio waves
02
03
Dipole Antenna
..SwitchesDipole Antenna.jpg
Two wires simple
antenna
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33. Symbols / conventions of Misc.
Sr.No. Symbol Component name Meaning
01
Motor
..SwitchesMotor.jpg
Electric motor
02
Transformer
..SwitchesTransformer.jpg
Change AC voltage
from high to low or
low to high.
03
Electric bell
..SwitchesElectric bell.jpg
Rings when
activated
04
Buzzer
..SwitchesBuzzer.jpg
Produce buzzing
sound
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34. Symbols / conventions of Misc.
Sr.No. Symbol Component name Meaning
05
Fuse
..SwitchesFuse.jpg
The fuse disconnects
when current above
threshold. Used to
protect circuit from
high currents.06
07
Bus
..SwitchesBus.jpg
Contains several
wires. Usually for
data / address.
08
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35. Symbols / conventions of Misc.
Sr.No. Symbol Component name Meaning
09
Optocoupler / Opto-
isolator
Optocoupler isolates
connection to other
board
10
Loudspeaker
..SwitchesLoudspeaker.jpg
Converts electrical
signal to sound waves
11
Microphone Converts sound waves
to electrical signal
12
Operational Amplifier
..SwitchesOperational
Amplifier.jpg
Amplify input signal
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36. Symbols / conventions of Misc.
Sr.No. Symbol Component name Meaning
13
Analog-to-digital
converter (ADC)
Converts analog signal
to digital numbers
14
Digital-to-Analog
converter (DAC)
Converts digital
numbers to analog
signal
15
Crystal Oscillator
..SwitchesCrystal Oscillator.jpg
Used to generate
precise frequency clock
signal
16
Schmitt Trigger Operates with
hysteresis to reduce
noise.2/6/2015 WPX ( 17005) 36

37. Symbols / conventions of Logic Gates
Sr.No. Symbol Component name Meaning
01
OR Gate Outputs 1 when
any input is 1.
02
AND Gate Outputs 1 when
both inputs are 1.
03
NOT Gate (Inverter) Outputs 1 when
input is 0
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38. Symbols / conventions of Logic Gates
Sr.No. Symbol Component name Meaning
04
NOR Gate Outputs 0 when
any input is 1.
05
NAND Gate Outputs 0 when
both inputs are 1.
06
XOR Gate Outputs 1 when
input is 0
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39. Symbols / conventions of Logic Gates
Sr.No. Symbol Component name Meaning
07
D Flip-Flop Stores one bit of
data
08
Multiplexer / Mux
4 to 1
Connects the output
to selected input
line.
09
Demultiplexer /
Demux
1 to 4
Connects selected
output to the input
line.
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40. IDENTIFICATION OF ELECTRONIC COMPONENTS
ASSIGNMENT NO.03
• Collect the catalog from internet for instruments
required for Electronic Workshop.
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41. Instruments used in Electronic Workshop
• Function Generator.
• Multimeter.
– Analog Multimeter.
– Digital Multimeter.
• Power Supply.
– AC Power Supply
– DC Power Supply.
– SMPS.
– Programmable Power Supply.
• Oscilloscope.
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42. Function Generator
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43. Analog Multimeter
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44. Digital Multimeter
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45. DC Power Supply
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46. Power Supply SMPS
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47. Oscilloscope
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48. Introduction and
demonstration of soldering

49. WHAT IS SOLDERING
• Soldering is the process of joining
metal leads, creating a mechanical
and electrical bond. As shown in the
figure, the lead of the resistor and the
pad of the circuit board are
mechanically attached and electrically
connected.

50. WHAT IS REQUIRED
• The tools needed for the soldering process:
– Safety glasses
– Soldering iron
– Solder
– Wire cutter
– Damp sponge

51. TOOLS
 Assemble the proper tools together.

52. WHY SAFETY GLASSES
• It is important always to wear the
safety glasses during the whole
soldering process to protect your
eyes against boiling solder particles
that fly up while the solder is melting
and pieces of leads that might fly in
any direction when they are cut.

53. WHAT IS A SOLDERING IRON
• The soldering iron is the tool that is
used to heat the joint. It has a tip that
is heated by an internal heating
element.

54. SOLDERING IRONS
Pencil tip Temperature Controlled

55. WHAT IS SOLDER
• Solder is the material that melts on the
joint attaching to both the component
lead and the pad on the circuit board.

56. WHAT OCCURS WHEN SOLDER MELTS
• As the solder melts during the soldering
process, it attaches to the component lead
and the pad.
• The flux flows into the joint dissolving existing
oxides on the leads and preventing the
formation of new ones. This facilitates the
formation of a good soldering joint.

57. Step 1:
WHAT ARE THE STEPS IN SOLDERING?

58. Prepare component for mounting.
• In this step you bend the leads of the
component at 90 degree angle to fit into the
holes of the circuit board. You can do this
with your hand or with the help of pliers. Be
sure that the leads are bent at the right
distance from the body of the component so
they fit comfortably in the holes on the board.

59. Step 2:
Mount component onto board

60. Mount component on board.
• In this step you insert the leads of the component into
the holes on the board, from the component side. The
body of the component should rest on the component
side of the board.
• It is a common incorrect practice among new students to
install the component on the soldering side (foil side) of
the board instead of the component side, or to install the
component away from the surface of the board, instead
of resting on the surface of the board, as shown in the
figure.

61. Step 3:

62. Bend component leads slightly.
• After you have inserted the leads of the
component into the holes on the board, you
should bend the component leads slightly to
hold the component in place while the board
is turned over to be soldered.

63. Step 4.
Heat iron. Clean tip with damp
sponge

64. Clean iron's tip.
• Before you start soldering and after the tip of
the iron has heated up, the tip of the iron
should be cleaned on a damp sponge and
tinned, by melting apiece of solder on the
iron's tip and then wiping the tip on the damp
sponge again.
• The tip of the iron should always have an even
shiny metal surface from the solder. Each time
oxide forms on the tip, clean the tip on the
damp sponge to make it shiny again.

65. Step 5.

66. Apply heat.
• In this step you apply heat to the joint to be
soldered by touching the tip of the iron firmly
against both the component lead, and the pad on
the board, simultaneously. Allow about three
seconds or more for the joint to heat up before
applying the solder.
• This is one of the most important steps in the
soldering process. If you do not heat up the joint
(lead and pad on the board) sufficiently you will
get a cold soldering joint which will have to be re-
soldered.

67. Step 6.
Apply Solder

68. Apply solder.
• After the joint has heated up, apply solder to
the point where the lead and the pad join.
Apply enough solder to create a "mountain "
of solder that attaches to both, the lead and
the pad, as shown in the drawing of step 8. A
common problem among new students is to
apply too little or too much solder, neither is
good.

69. Step 7.

70. Remove solder.
• After the solder has melted on
the joint forming a nice
connection as the one shown in
steps 8 and 9, remove the solder
wire from the joint then remove
the iron.

71. Step 9:

72. Inspect the soldering joint.
• After the joint has cooled off, visually inspect the
joint that you have created. It should have a shiny
and smooth surface and it should attach to both
the component lead, and the pad on the board. In
the next transparency we will see what good and
bad soldering joints look like.
• If, during the inspection, you recognize that your
soldering is not good, you will have to re-solder
the connection by reheating the joint with the
iron, until the solder melts and then applying a
little more solder.

73. Step I0:
 Cut excess lead

74. Cut off component leads.
• After you have soldered a joint the next step is
to cut off the excess component lead using a
wire cutter. Trim the lead off the component as
close to the solder joint as possible. This is
another important step in the assembly process
that can not be avoided because untrimmed
component
• leads might cause short circuits between
metallic traces on the board.

75. Good solder joint.
As we have said before, a good soldering joint has a
shiny and smooth surface and attaches to both the
component lead, and the pad on the board.

76. Cold solder join: You can recognize a cold solder
joint because it is dull (not shiny) and irregular (not
smooth). Cold solder joints do not make good
electrical connections and should be re-solder.

77. Solder not attached to lead: In this type of
defective soldering joint the solder is attached
to the pad of the board but not to the lead of
the component.

78. In this type of defective soldering joint
the solder is attached to the lead of
the component but not to the pad on
the board.
Solder not attached to pad

79. This problem is caused by not
trimming the component leads after
soldering the joint.
Leads not trimmed

80. Leads not trimmed.
• Leads that are not trimmed pose a
potential problem because they can
be touching each other or touching
other parts of the pad, producing
short circuits and damaging the
components. Never leave untrimmed
leads after the soldering is
completed.

81. Solder bridge:
• Solder bridge: A solder bridge is a bridge
made with solder that is connecting two pads
(or foil traces) that should not be connected.
Sometimes solder bridges are easy to detect
and other times they are so tiny that they can
only be detected with the use of a magnifying
glass.

82. Solder bridge:
Solder bridges can be eliminated
by melting them with the soldering
iron.