Course Code: GED1103
Course Name: Manufacturing Practices
Laboratory
Department of Electronics and
Communication Engineering
Name
:
RRN
:
BONAFIDE CERTIFICATE
Certified that this is the bonafide record of the workdone by _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
R R N _ _ _ _ _ _ _ _ _ _ _ of I-semester B.Tech __________________________ in
the course GED 1103 Manufacturing Engineering Practice Laboratory during the
year 2021- 2022.
Faculty in-charge
Identifications
and
symbolic representation
1
of active and passive
electronic components
Soldering,
2
De-soldering
& tracing of electronic
circuits and checking its
continuity
3
Assembly of A.C to D.C
Circuits in Bread board
Avg :
Sign
(100)
Total
(30)
Viva
(30)
Performance
(40)
Execution
Name of
Experiment
Date
S. No.
Index
Identifications and symbolic representation of active and passive
electronic components
Ex.No :_____________
Date : _____________
Aim :
To identify the symbolic representation of active and passive electronic
components
Theory:
The electronic Components have terminals and each will have its own name
and polarities. The Basic is Passive and Active components, R C L (Resistor,
Capacitor, Inductor) are passive and Most of the Semiconductors are Active
components.
Resistor
Resistor component gives resistance that is barrier to the current flow in a circuit.
There are two different symbols are widely used in schematics that is Zigzag format
(US style) and Rectangle shape, this will have two pins and three pins if variable
resistor. Unit of resistor is Ohm Ω.
Defining the value of resistor from its color bands:
1. First find the tolerance band, which is typically gold (5%) and sometimes
silver (10%), and hold the resistor such that this band is at your right-hand
side.
2. Starting from the other end, identify the first band at your left-hand side;
write down the number associated with that color.
Example: First band – BLUE- write down ‘6’.
3. Then identify the color band next to it.
Example: Second band - RED, write down a '2' next to the ‘6’.
4. The first two bands are called digit band.
5. Now read the third or multiplier band and write down that number of zeros
Example: Third band - GREEN, multiply the quantity indicated by the digit
bands with 10^5.
The resistance value of a sample resistor with a color code as ‘blue-red-green-gold”
is 62*10^5 Ω = 6.2MegaΩ(1M Ω=10^6 Ω).
Measurement of Resistance using Multimeter:
• Switch on multi-meter
• Switch to Ohmmeter
• Enable “Auto Range” in order to get the maximum number of significant
digits during measurement.
• Hold the resistor in your left hand and connect one end of a banana-to-minigrabber cable to the instrument and the other end to the resistor.
• Record the resistance value and the unit from the LCD screen
Calculate Percentage Error:
For a given resistor, we measure the difference between its nominal resistance
and measured resistance in the percentage, which is called percentage error, given
by
PE =
| NV − MV |
*100 %
NV
,
Where PE represents for percentage error, NV for nominated value and MV for
measured value.
Tabulation:
Read the color codes of 2 resistors and identify their resistances.
Resistor
Color
codes
Nominated
value
Measured
value
Percentage of
error
1
2
Capacitor
The capacitor reacts as static energy storage some times, Non-polarized (two
parallel line) capacitor have two equal plate separated by insulator and Polarized
(one straight and one curved line) capacitor have positive and negative pins.
Capacitor Value Calculation:
Ex1: Let the number 104 is written on the capacitor
Then, capacitor value is given by
104 = 10x104 x10−12 = 10−7 = 0.1µF.
Ex2:223 = 22 ∗ 103 ∗ 10−12 = 22 ∗ 10−9 = 22𝑛𝐹 = 0.022µ𝐹.
Inductor
The Inductor reacts as magnetic storage element; it is represented as loopy coils, or
curved bumps. This element doesn’t have polarities.
Diode
The Active devices are starts from diode, symbol represented with Triangle Arrow
pressed up against a line. The diode have polarities called Anode(triangle pin) and
Cathode(straight line) hence it should be identified for employment.
Transistor
This components transfers resistance between two circuits based on the layers it is
called as NPN or PNP and also it is named as BJT (Bi Junction Transistor).
Thyristor
Thyristors are active device having more than two junction in layer structure and
used in high voltage and high power applications.
MosFET
Metal oxide semiconductor field effect transistor is the expansion of MosFET, these
are reacts as voltage control device having three terminals. Based on the diffusion it
is classified as Depletion and Enhancement and depends on the channel it is
classified as N and P channel MosFET.
Logic Gate
Logic Gates are comes in a Integrated Circuit (IC) format for an example IC7400
(four nand gates), The Logic operations are AND, OR, NOT, EXOR, NAND, NOR
having unique symbols. Based on the requirements we can choose two, three are
more input output pin logic gates.
Integrated Circuit
The Integrated Circuits (IC) are represented in many ways but mostly with big
arrow for operational amplifier or square box with pin functions.
Switches
Switches makes circuit connected or disconnected (ON or OFF), depends on the
number of poles and throws it is classified. Other than this push button and toggle
switches are also available in circuit diagram.
Power Supply
These are represents Power supply and bias details in circuit diagram. Symbol with
+ and – indicates DC (direct current) source and symbol with sin wave indicates AC
(alternating current) source.
Fuse
The Fuse reacts as safety element to protect circuit against large current and sudden
urges of current. The fuse are comes in different structure and different materials the
basic symbol given here, PTC represents positive temperature coefficient
(temperature dependent resistor) and it is also reacts as fuse.
Transformer
The Transformer is step down or step up the voltage and current, for electronic
circuits we use Step down and isolation transformers mostly in some other case like
inverter we use step up transformer. Transformer with two terminal secondary and
three terminal (center tapped) secondary are illustrated.
Relay
The Relay are Electromagnetic Switches and makes or disconnects circuits when
the relay coil gets energy. Depends on the pole and contact relays are classified.
Relay Switch gives N/O (normally open) and N/C (normally close) terminals when
the relay coil gets energy N/O becomes closed and N/C becomes opened terminals.
Bread Board:
A breadboard is used to make up temporary circuits for testing or to try out an idea.
No soldering is required so it is easy to change connections and replace
components. Parts will not be damaged so they will be available to re-use
afterwards.
Multimeter:
A multimeter or a multitester, also known as a VOM (Volt-Ohm meter), is
an electronic measuring instrument that combines several measurement functions in
one unit. A typical multimeter may include features such as the ability to measure
voltage, current and resistance. Multimeter may be used in analog or digital circuitsanalogmultimeters (AMM)
and digital
multimeters (often
abbreviated DMM or DVOM).
CRO:
The cathode-ray oscilloscope (CRO) is a common laboratory instrument that
provides accurate time and amplitude measurements of voltage signals over a wide
range of frequencies. Its reliability, stability, and ease of operation make it suitable
as a general purpose laboratory instrument.
A cathode ray oscilloscope (CRO) is used to see the waveform of a repetitive
electronic signal. The signal is amplified or attenuated as required and used to
deflect an electron beam in the vertical direction. This electron beam is deflected in
the horizontal direction at a suitable speed. The electron beam impinging on a
phosphorescent screen enables the viewer to see the wave shape of the signal.
Power Supply: Power supply is a reference to a source of electrical power. A device
or system that supplies electrical or other types of energy to an output load or group
of loads is called a power supply unit or PSU. The term is most commonly applied
to electrical energy supplies, less often to mechanical ones, and rarely to others.
Regulated power supply is a power supply containing means for maintaining
essentially constant output voltage or output current under changing load
conditions. The fixed voltage power supply is useful in applications where an
adjustable output is not required. This supply is simple, but very flexible as the
voltage it outputs is dependant only on the regulator and transformer you choose.
Function Generator:
A function generator is usually a piece of electronic test equipment or software used
to generate different types of electrical waveforms over a wide range of frequencies.
Some of the most common waveforms produced by the function generator are the
sine, square, triangular and sawtooth shapes.
Result:
Soldering and De-soldering of electronic circuits and checking its
continuity
Ex.No :_____________
Date : _____________
Aim:
To perform soldering and desoldering of a circuit and also to check its
continuity.
Apparatus Required:
Soldering iron, solder, flux, wick or solder sucker, Resistors.
Theory:
1. SAFETY PRECAUTIONS
• Never touch the element or tip of the soldering iron.
• Take great care to avoid touching the mains flex with the tip of the iron.
• Always return the soldering iron to its stand when not in use.
• Allow joints a minute or so to cool down before you touch them.
• Work in a well-ventilated area.
• Wash your hands after using solder.
1.1 soldering.
Soldering is a process in which two or more metal items are joined together
by melting and flowing a filler metal into the joint, the filler metal having a
relatively low melting point. The filler metal used in the process is called solder.
2. SOLDERING ACCESSORIES
2.1 Soldering Iron
A soldering iron is a tool used for applying heat to two adjoining metal parts
such that solder may melt and flow between those parts, binding them securely and
conductively. A soldering iron is composed of a heated metal tip and an insulated
handle. Heating is often achieved electrically, by passing a current, supplied through
an electrical cord or a battery, through a heating element
The following are the different soldering iron types
1. Temperature-controlled iron. A soldering iron with electronic temperature
control is highly recommended. Irons without temperature control can reach
temperatures that are high enough to irreversibly damage the tips. Since
temperature is not proportional to wattage with this type of iron, the wattage
rating is relatively unimportant. A higher wattage iron results in a faster
temperature recovery time between soldering operations (40 W to 60 W units
seem to work well).
2. Non-temperature-controlled iron. A low wattage (10 W to 25 W) pencil-type
(not gun-type) can be used but is not recommended. This type of iron must be
unplugged when not in use to save the tips. The temperature is proportional to
wattage and most of these types of soldering irons will reach temperatures
that can destroy tips quickly.
3. Modified, non-temperature-controlled iron. A 10 W to 40 W pencil-type iron
can be operated from a variac to limit the wattage (and therefore the
temperature) and is a reasonable substitute for a temperature-controlled iron.
However, a variac can cost more than a temperature controlled station and
will yield less satisfactory results.
2.2 Solder
Solder is an alloy (mixture) of tin and lead, typically 60% tin and 40% lead. It
melts at a temperature of about 200°C. Coating a surface with solder is called
‘tinning’ because of the tin content of solder. Lead is poisonous and you should
always wash your hands after using solder. Solder for electronics use contains tiny
cores of flux, like the wires inside a mains flex. The flux is corrosive, like an acid,
and it cleans the metal surfaces as the solder melts. This is why you must melt the
solder actually on the joint, not on the iron tip. Without flux most joints would fail
because metals quickly oxidise and the solder itself will not flow properly onto a
dirty, oxidised, metal surface.
The following are the different solder types
1. Rosin core. 60/40 Sn/Pb (M.P. 361-376°F) and 63/37 Sn/Pb (M.P. 361°F)
solders are the most common types used for electronics assembly. These
solders are available in various diameters and small diameters are most
appropriate for small electronics work (0.02” - 0.05” dia. is recommended).
2. Lead-free. Lead-free solders are used as more environmental-friendly
substitutes for leaded solder, but they are typically not as easy to use mainly
because of their higher melting point and poorer wetting properties.
3. Silver. Silver solders are typically used for low resistance connections but
they have a higher melting point and are more expensive than Sn/Pb solders.
4. Acid-core. NEVER USE ACID CORE SOLDERS FOR ELECTRONICS!
They are intended for plumbing or non-electronics assembly work. The acidcore flux will cause corrosion of circuitry and can damage components.
2.3 Flux
Flux is used to prepare the surfaces of the conductors prior to soldering. Flux
removes oxidation from the conductors and maintains oxide-free surfaces at
elevated temperature during the soldering process. This allows all surfaces to “wet”
properly.
The following are the different solder types
1. The most common flux used in hand soldering of electronic components is
rosin, a combination of mild organic acids extracted from pine trees (some
manufacturers use synthetic compounds).
2. Although fluxes can be obtained in liquid or paste form, they are typically
contained in solders (rosin core) used for hand assembly of electronics.
Fluxes labeled as “Acid” are strong acids (as opposed to the mild rosins) and
should never be used for electronics assembly.
2.4 Sponge
A sponge is required for keeping tips clean for best heat transfer. A clean
soldering iron tip is one of the most important steps towards producing good solder
joints.Most soldering stations come with sponges and sponge holders.
2.5 Tips
Currently, most tips sold for electronics work are iron-clad copper and have
long life spans. Iron-clad tips cannot be filed or sanded when they become oxidized;
they must be replaced. Many tip shapes are available, but miniature needle or chisel
point tips are best for most work. The tip shape should be chosen to provide the
highest contact surface area for best heat conduction. Minimizing the shank length
can increase the heat transfer from the iron (heater) to the tip. Copper tips can still
be purchased but are not recommended because of their short life span and poor
wetting properties.
3. NECESSARY TOOLS
These are the recommended minimum complement of tools for soldering:
1. Miniature needle-nose pliers
2. Miniature side cutters
3. Wire strippers
4. Solder removal tool (“Solder Sucker”)
5. Water bottle
6. Safety glasses
4. MAKING SOLDERED JOINTS
4.1 Preparing the Soldering Iron
•Place the soldering iron in its stand and plug in.
The iron will take a few minutes to reach its operating temperature of about 400°C.
• Dampen the sponge in the stand.
The best way to do this is to lift it out the stand and hold it under a cold tap for a
moment, then squeeze to remove excess water. It should be damp, not dripping wet.
• Wait a few minutes for the soldering iron to warm up.
You can check if it is ready by trying to melt a little solder on the tip.
• Wipe the tip of the iron on the damp sponge.
This will clean the tip.
• Melt a little solder on the tip of the iron.
This is called 'tinning' and it will help the heat to flow from the iron’s tip to the
joint. It only needs to be done when you plug in the iron, and occasionally while
soldering if you need to wipe the tip clean on the sponge.
• You are now ready to start soldering!
Please turn the page for further instructions...
4.2 Making Soldered Joints
• Hold the soldering iron like a pen, near the base of the handle.
Imagine you are going to write your name! Remember to never touch the hot
element or tip.
• Touch the soldering iron onto the joint to be made.
Make sure it touches both the component lead and the track. Hold the tip there for a
few seconds and...
• Feed a little solder onto the joint.
It should flow smoothly onto the lead and track to form a volcano shape as shown in
the diagram below. Make sure you apply the solder to the joint, not the iron.
• Remove the solder, then the iron, while keeping the joint still.
Allow the joint a few seconds to cool before you move the circuit board.
• Inspect the joint closely.
It should look shiny and have a ‘volcano’ shape. If not, you will need to reheat it
and feed in a little more solder. This time ensure that both the lead and track are
heated fully before applying solder.
5. SOLDERING ADVICE FOR COMPONENTS
Some components require special care when soldering. Many must be placed
the correct way round and a few are easily damaged by the heat from soldering.
Appropriate warnings are given in the table on the next page, together with other
advice which may be useful when soldering.
Components
Resistors
Pictures
Soldering advice
No special precautions are required.
Connect either way round.
Diodes
Diodes must be connected the correct way
round: a = anode, k = cathode.
Use a heat sink with germanium diodes.
IC holders
Ensure the notch is at the correct end.
(DIL sockets)
Do not insert the IC at this stage to
prevent it being damaged by heat.
Presets (small
No special precautions are required.
variable
On stripboard take care to ensure you
resistors)
insert them the correct way round.
Capacitors,
No special precautions are required.
non-polarised
Connect either way round.
(less than 1μF)
Take care to identify their value.
Capacitors,
Electrolytic capacitors must be connected
the correct way round, they are marked
electrolytic
with + or - near one lead.
(1μF
and
greater)
LEDs
LEDs must be connected the correct way
round: a = anode, k = cathode.
(Light
Emitting
Use a heat sink with small (3mm) LEDs.
Diodes)
Transistors
Transistors have three leads and must be
connected the correct way round.
Use a heat sink clipped to each lead in
turn between the joint and the transistor.
Integrated
When all soldering is complete, carefully
Circuits
insert ICs the correct way round in their
(ICs
or
‘chips’)
holders. Make sure all the pins are lined
up before pushing in firmly.
6.Desoldering Guide
1 Desoldering
At some stage you will probably need to desolder a joint to remove or reposition a wire or component. There are two ways to remove the solder
1.1 With a desoldering pump (solder sucker)
• Set the pump by pushing the spring-loaded plunger down until it locks.
• Apply both the pump nozzle and the tip of your soldering iron to the joint.
• Wait a second or two for the solder to melt.
• Then press the button on the pump to release the plunger and suck the molten
solder into the tool.
• Repeat if necessary to remove as much solder as possible.
• The pump will need emptying occasionally by unscrewing the nozzle.
1.2 With a solder remover wick (copper braid)
• Apply both the end of the wick and the tip of your soldering iron to the joint.
•
As the solder melts most of it will flow onto the wick, away from the joint.
• Remove the wick first, then the soldering iron.
• Cut off and discard the end of the wick coated with solder.
After removing most of the solder from the joint(s) you may be able to remove the
wire or component lead straight away (allow a few seconds for it to cool). If the
joint will not come apart easily apply your soldering iron to melt the remaining
traces of solder at the same time as pulling the joint apart, taking care to avoid
burning yourself.
SERIES CIRCUITS
Series circuits are sometimes called current-coupled or daisy chain-coupled. The
current in a series circuit goes through every component in the circuit. Therefore, all
of the components in a series connection carry the same current. There is only one
path in a series circuit in which the current can flow.A series circuit's main
disadvantage or advantage, depending on its intended role in a product's overall
design, is that because there is only one path in which its current can flow, opening
or breaking a series circuit at any point causes the entire circuit to "open" or stop
operating.
Current
In a series circuit the current is the same for all elements.
Resistors
The total resistance of resistors in series is equal to the sum of their individual
resistances:
Parallel circuits
If two or more components are connected in parallel they have the same potential
difference (voltage) across their ends. The potential differences across the
components are the same in magnitude, and they also have identical polarities. The
same voltage is applicable to all circuit components connected in parallel. The total
current is the sum of the currents through the individual components, in accordance
with Kirchhoff’s current law.
Voltage
In a parallel circuit the voltage is the same for all elements.
Resistors
The current in each individual resistor is found by Ohm's law. Factoring out the
voltage gives
.
To find the total resistance of all components, add the reciprocals of the resistances
of each component and take the reciprocal of the sum. Total resistance will
always be less than the value of the smallest resistance:
.
For only two resistors, the unreciprocated expression is reasonably simple:
OBSERVATION:
Series Circuit :
Theoritical(NV)
Practical (MV)
𝑅1
𝑅2
𝑅𝑇 = 𝑅1 + 𝑅2
Parallel Circuit:
Theoritical(NV)
Practical (MV)
R3
R4
RR
RT = 3 4
R3 + R4
Result:
Thus, a simple series and parallel connection of resistor is performed using
soldering.
ASSEMBLY OF A.C TO D.C CIRCUITS IN BREAD BOARD
Ex.No :_____________
Date : _____________
Aim
To construct a Half wave rectifier , an A.C to D.C Circuit in Bread Board and
observe its output response.
Apparatus Required:
S.
Item Description
Specification
No.
Quantity in
Nos.
1
PN diode
1N4007
1
2
Resistor
1 KΩ\1W
1
3
Transformer
(0-230)V\ (6-0-6) V – 250
1
mW
4
Bread Board
--
1
5
CRO with BNC
Dual trace\15 MHz
1
Probe
6
Connecting wires
Sufficient length
few
7
Multi meter
Sony \ Philips make
1
Theory:
The process of converting alternating voltage/current to direct voltage/current
is called rectification. An electronic device that offers a low resistance to current in
one direction and a high resistance in the other direction is capable of converting a
sinusoidal waveform into a unidirectional waveform. Diodes have this
characteristic, which makes it a useful component in the design of rectifiers. In
order to achieve a constant/pure DC voltage at the output, filtering should be done
to the pulsating DC output of the rectifier.
Half Wave Rectifier (HWR)
The half-wave rectifier circuit using a semiconductor diode (D) with a load
resistance RL but no smoothing filter is given in the figure. The diode is connected
in series with the secondary of the transformer and the load resistance RL. The
primary of the transformer is being connected to the ac supply mains.
During positive half cycle of secondary voltage (input voltage), the diode D1
is forward biased and D2is reverse biased. The diode D1 conducts and current flows
through load resistor RL.
During the positive half cycle, the diode is under forwarding bias condition and it
conducts current to RL (Load resistance). A voltage is developed across the load,
which is the same as the input AC signal of the positive half cycle. Alternatively,
during the negative half cycle, the diode is under reverse bias condition and there is
no current flow through the diode. Only the AC input voltage appears across the
load and it is the net result which is possible during the positive half cycle. The
output voltage pulsates the DC voltage.
Circuit Diagram:
PROCEDURE:
1. Make the Connections as per the circuit diagram.
2. Connect the primary side of the transformer to ac mains and the secondary side to
the rectifier input.
3. Observe input and output waveforms with the help of CRO.
4. Note down the readings for voltage and frequency of input and output
waveforms.
* Further a capacitor of 10 µF and a regulator IC 7805 is addad to the circuit to get a
perfect DC voltage from a pulsating DC across the resistor.
OBSERVATION TABLE:
Observation
Amplitude (V)
Time Period (ms)
Input
Output across resistor
RESULT:
Thus AC to DC Circuit is constructed using bread board and its output
waveform is obtained.