Final Radar ultrasonic

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    ACKNOWLEDGMENT

    We own our regards and heartiest gratitude to Dr. I.P Singh (Director) and Er. ManojArora (Head of Department of Electronics and Communication) for their guidance, constant

    encouragement, constructive suggestions, thought provoking decisions and guidance to

    complete the project in entire duration of this work. At the very outset, we are highly

    indebted to JMIT, Radaur for giving us an opportunity to carry out our project on

    ULTRASONIC RADAR.

    We would specially thank Er. Vishal Chaudhary (Asst. Professor in ECE Dept.), our

    Project Guide, for giving time and guidance throughout our project period without whom it

    would have been impossible to attain success.

    No good work can be done alone, as the saying goes is truly applicable. A friend,

    Philosopher and Our Guide always acts source of inspiration and motivation to accomplish a

    given task. Our humble and sincere thanks to our project guide for his guidance and

    direction, which helped, escalate our practical knowledge.

    The co-operation and our combined efforts lead to the completion of the project.

    Our heartiest debts to our parents for their encouragement and understanding which has been

    a timely factor in completion of this project.

    SHIVANSH KANSAL (1209099)

    VISHAL KAKKAR (1209121)

    VARUN HOODA (1209113)

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    ABSTRACT

    The goal of our project is to design an Ultrasonic Radar, which is used for the purpose ofObject Detection via transmission and reception of Ultrasonic waves.

    The circuit of Ultrasonic Radar generates (transmits) ultrasonic sound of frequency between

    40 and 50 kHz. As with any other remote control system this circuit comprises of a mini

    transmitter and a receiver circuit. Transmitter generates ultrasonic sound and the receiver

    senses ultrasonic sound from the transmitter and switches on a relay which further actuates

    Buzzer and few LEDs attached to it.

    The ultrasonic transmitter uses a 555 based astable multivibrator. It oscillates at a frequency

    of 40-50 kHz. An ultrasonic transmitter transducer is used here to transmit ultrasonic sound

    very effectively. The ultrasonic receiver circuit uses an ultrasonic receiver transducer to

    sense ultrasonic signals. It also uses a two-stage amplifier, a rectifier stage, and an

    operational amplifier in inverting mode. Output of op-amp is connected to a relay through a

    complimentary relay driver stage. The relay can be used to control any electrical or

    electronic equipment.

    Although the project aimed only at transmitting and receiving through ultrasonic radar but its

    implementations and applications are vast. Ultrasonic Radar can be made of use in Security

    Alarms, Anti-theft Cars, Missile Launching, Detection of Enemies, Air Traffic Control,

    Defence and many more.

    TECHNICAL SPECIFICATIONS :-

    Working voltage : 12VDC

    Current: 30 mA

    The above description gives a brief view about our project ULTRASONIC RADAR.

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    TABLE OF FIGURES

    Figure No. Figure Name Page No.Fig-1 Ultrasonic radar project(Top view) 10

    Fig-2 Ultrasonic radar project(side view) 11

    Fig-3 Circuit Diagram of ultrasonic radar 15-16

    Fig-4 PCB Layout 17

    Fig-5 Pin Diagram Of HEF4017BMSI 18

    Fig-6 Functional Diagram OF HEF4017BMSI 19

    Fig-7 Logic Diagram of 5 STAGE JOHNSON COUNTER21

    Fig-8 555 TIMER IC22

    Fig-9 555 MONOSTABLE MODE 22

    Fig-10 555 ASTABLE MODE 23

    Fig-11 Pin diagram of ULN2803A 24

    Fig-12 Logic diagram 25

    Fig-13 Schematci (each darlington pair) 25

    Fig-14 Power supply 26

    Fig-15 DC power supply 27

    Fig-16 Ammeter 28

    Fig-17 Voltmeter of 10 V 29

    Fig-18 Voltmeter of 150 V 29

    Fig-19 Multimeter as a Ammeter 30

    Fig-20 Multimeter as Voltmeter 31

    Fig-21 Symbol of LED 32

    Fig-22 Circuit of LED 32

    Fig-23 Seven Segment Display 33

    Fig-24 Stepper Motor 34

    Fig-25 Poles of Motor 34

    Fig-26 Ultrasonic Sensor 35

    Fig-27 TO-220(T),TO-3(k) 37

    Fig-28 PCB Layout 38

    Fig-29 Resistor 39

    Fig-30 Colour Coding 40

    Fig-31 Colour Coding Table 41

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    Fig-32 Transistor 42

    Fig-33 Symbol Of Transistor 43

    Fig-34 Capacitor 44

    Fig-35 Types of Capacitors 44Fig-36 Symbols of Capacitor 45

    Fig-37 Coding in Capacitor 45

    Fig-38 105k Capacitor 46

    Fig-39 IC Socket 46

    Fig-40 Relay 47

    Fig-41 Types of relays 48

    Fig-42 Soldering Iron50

    Fig-43 Soldering Stand 51Fig-44 Soldering Wire 52

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    TABLE OF CONTENTS

    CHAPTER

    NO.

    NAME OF THE CHAPTER PAGE NO.

    1.

    ULTRASONIC RADAR

    1. INTRODUCTION

    2. CONSTRUCTION

    3. COMPONENTS

    4. WORKING

    5. CIRCUIT DIAGRAM OF ULTRASONIC RADAR

    6. PCB LAYOUT OF ULTRASONIC RADAR

    7-15

    2.

    IC USED

    1. HEF4017BMSI

    2. 555 TIMER IC

    3. ULN2803

    16-22

    3.

    COMPONENTS USED

    1. POWER SUPPLY

    2. TESTING & CALIBRATION OF EQUIPMENT

    3. LIGHT-EMITTING DIODE (LED)

    4. SEVEN SEGMENT DISPLAY

    5. STEPPER MOTOR

    6. ULTRASONIC SENSOR

    7. LM78XX (SERIES VOLTAGE REGULATORS)

    8. PCB LAYOUT

    9. RESISTORS

    10. TRANSISTORS

    11. CAPACITORS

    12. IC SOCKET

    13. RELAY

    23-46

    4. 47-49

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    TOOLS USED

    1. SOLDERING IRON

    2. SOLDERING STAND

    3. SOLDER WIRE

    5.

    PRINTED CIRCUIT BOARD

    1. CLEANING

    2. TIPS

    3. PCB PREPARATION

    4. TESTING 50-52

    6. CONCLUSION 53

    7. REFERENCE 54

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    CHAPTER-1

    ULTRASONIC RADAR

    1.1 INTRODUCTION

    This is a very interesting project with many practical applications in security and alarm

    systems for homes, shops and cars. It consists of a set of ultrasonic receiver and transmitter

    which operate at the same frequency. When something moves in the area covered by the

    circuit the circuits fine balance is disturbed, the alarm is triggered and LEDs starts

    glowing. The circuit is very sensitive and can be adjusted to reset itself .

    An electronic circuit consist of interconnection of various electrical or electronic

    components or devices to fulfill a desired function. In electronic circuit, symbols are used to

    represent these components or devices. It includes active and passive components.

    A circuit designer must have knowledge of different types of components, there working

    application, characteristics, operation range, inputs, outputs and other working conditions.

    The frequent knowledge of all components being used by a designer in a circuit is essential

    for designer.

    During designing a new circuit, a designer must have an idea of the features of the final

    products and also know about the working condition, range and other essential characteristic.

    Such as environmental conditions; as most of component/devices change their characteristics

    with change in environment, to be desired for the final equipment. During designing circuit;

    the temperature conditions of the place where the equipment is to be placed must also be

    taken into account as it has tremendous effect on the performance of the circuit.

    A designer should always remain in touch with latest inventions and developments which are

    taking place in the field of circuit designer. At the time of selection of a component in a

    circuit, a designer must keep in mind about the substitute components which will give better

    performance and high accuracy to the final equipment.

    1.2 CONSTRUCTION

    First of all let us consider a few basics in building electronic circuits on a printed

    circuit board. The board is made of a thin insulating material clad with a thin layer of

    conductive copper that is shaped in such a way as to form the necessary conductors between

    the various components of the circuit. The use of a properly designed printed circuit board is

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    very desirable as it speeds construction up considerably and reduces the possibility of

    making errors. Smart Kit boards also come pre-drilled and with the outline of the

    components and their identification printed on the component side to make construction

    easier. To protect the board during storage from oxidation and assure it gets to you in perfect

    condition the copper is tinned during manufacturing and covered with a special varnish that

    protects it from getting oxidised and also makes soldering easier. Soldering the components

    to the board is the only way to build your circuit and from the way you do it depends greatly

    your success or failure. This work is not very difficult and if you stick to a few rules you

    should have no problems. The soldering iron that you use must be light and its power should

    not exceed the 25 Watts.

    The tip should be fine and must be kept clean at all times. For this purpose come very

    handy specially made sponges that are kept wet and from time to time you can wipe the hot

    tip on them to remove all the residues that tend to accumulate on it. DO NOT file or

    sandpaper a dirty or worn out tip. If the tip cannot be cleaned, replace it. There are many

    different types of solder in the market and you should choose a good quality one that

    contains the necessary flux in its core, to assure a perfect joint every time. DO NOT use

    soldering flux apart from that which is already included in your solder. Too much flux can

    cause many problems and is one of the main causes of circuit malfunction. If nevertheless

    you have to use extra flux, as it is the case when you have to tin copper wires, clean it very

    thoroughly after you finish your work. In order to solder a component correctly you should

    do the following:

    Clean the component leads with a small piece of emery paper. Bend them at the correct

    distance from the components body and insert the component in its place on the board.

    You may find sometimes a component with heavier gauge leads than usual, that are too thick

    to enter in the holes of the p.c. board. In this case use a mini drill to enlarge the holes

    slightly. Do not make the holes too large as this is going to make soldering difficult

    afterwards.

    Take the hot iron and place its tip on the component lead while holding the end of the

    solder wire at the point where the lead emerges from the board. The iron tip must touch the

    lead slightly above the p.c. board.

    When the solder starts to melt and flow wait till it covers evenly the area around the

    hole and the flux boils and gets out from underneath the solder. The whole operation shouldnot take more than 5 seconds. Remove the iron and allow the solder to cool naturally without

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    blowing on it or moving the component. If everything was done properly the surface of the

    joint must have a bright metallic finish and its edges should be smoothly ended on the

    component lead and the board track. If the solder looks dull, cracked, or has the shape of a

    blob then you have made a dry joint and you should remove the solder (with a pump, or a

    solder wick) and redo it.

    Take care not to overheat the tracks as it is very easy to lift them from the board and

    break them. When you are soldering a sensitive component it is good practice to hold the

    lead from the component side of the board with a pair of long-nose pliers to divert any heat

    that could possibly damage the component.

    Make sure that you do not use more solder than it is necessary as you are running the

    risk of short-circuiting adjacent tracks on the board, especially if they are very close

    together.

    When you finish your work cut off the excess of the component leads and clean the

    board thoroughly with a suitable solvent to remove all flux residues that may still remain on

    it.

    There are quite a few components in the circuit and you should be careful to avoid

    mistakes that will be difficult to trace and repair afterwards. Solder first the pins and the IC

    sockets and then following if that is possible the parts list the resistors the trimmers and the

    capacitors paying particular attention to the correct orientation of the electrolytic.

    Solder then the transistors and the diodes taking care not to overheat them during

    soldering. The transducers should be positioned in such a way as they do not affect each

    other directly because this will reduce the efficiency of the circuit. When you finish

    soldering, check your work to make sure that you have done everything properly, and then

    insert the ICs in their sockets paying attention to their correct orientation and handling IC3

    with great care as it is of the CMOS type and can be damaged quite easily by static

    discharges.

    Do not take it out of its aluminum foil wrapper till it is time to insert it in its socket,

    ground the board and your body to discharge static electricity and then insert the IC carefully

    in its socket. In the kit you will find a LED and a resistor of 560 which will help you to make

    the necessary adjustments to the circuit. Connect the resistor in series with the LED and then

    connect them between point 9 of the circuit and the positive supply rail (point 1).

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    Connect the power supply across points 1 (+) and 2 (-) of the p.c. board and put P1 at

    roughly its middle position. Turns then P2 slowly till the LED lights when you move your

    fingers slightly in front of the transducers. If you have a frequency counter then you can

    make a much more accurate adjustment of the circuit. Connect the frequency counter across

    the transducer and adjust P2 till the frequency of the oscillator is exactly the same as the

    resonant frequency of the transducer. Adjust then P1 for maximum sensitivity. Connecting

    together pins 7 & 8 on the p.c. board will make the circuit to stay triggered till it is manually

    reset after an alarm. This can be very useful if you want to know that there was an attempt to

    enter in the place which are protected by the radar.

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    Fig .1 Ultrasonic radar project

    1.2 COMPONENTS

    Transmitter Parts:

    IC1 NE555 timer IC

    VR1 10k variable resistor

    R1 4.7k resistor

    R2 18k potentiometer

    R3 1k resistor

    R4, R5 220 ohm resistor

    C1 680 picofarad capacitor

    C2 0.01uf capacitor

    D1, D2 1N4148 Diode

    T1 SL100 NPN transistor T2 SK100 PNP transistor

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    S1 SPST momentary contact switch

    XMTR ultrasonic transmitter 40-50khz

    Receiver Parts:

    RCVR Ultrasonic Receiver 40-50khz

    RL1 6volt 200ohm resistor

    IC2 CA3140

    VR2 250k Variable Resistor

    R6 390k Resistor

    R7 470k Resistor

    R8, R12 15k Resistor

    R9 12k

    R10, R13 10k

    R11 4.7k

    R14 100k Resistor

    R15 33 ohm Resistor

    C3 0.22uf ceramic capacitor

    C4 0.1uf ceramic capacitor

    C5 560n ceramic capacitor

    T3,T4 BC548 NPN Transistor

    T5 BC558 PNP Transistor

    T6 SL100 NPN Transistor

    D3,D4,D5 1N4148 Diode

    STEPPER MOTOR

    BUZZER

    1.3 WORKING

    The circuit described generates (transmits) ultrasonic sound of frequency between 40 and 50

    kHz. As with any other remote control system this circuit comprises of a mini transmitter

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    and a receiver circuit. Transmitter generates ultrasonic sound and the receiver senses

    ultrasonic sound from the transmitter and switches on a relay.

    The ultrasonic transmitter uses a 555 based astable multivibrator. It oscillates at a frequency

    of 40-50 kHz. An ultrasonic transmitter transducer is used here to transmit ultrasonic sound

    very effectively. The transmitter is powered from a 9-volt power supply made from AC

    220v. The ultrasonic receiver circuit uses an ultrasonic receiver transducer to sense

    ultrasonic signals. It also uses a two-stage amplifier, a rectifier stage, and an operational

    amplifier in inverting mode. Output of op-amp is connected to a relay through a

    complimentary relay driver stage. A 9-volt battery eliminator can be used for receiver

    circuit, if required. When switch S1 of transmitter is pressed, it generates ultrasonic sound.

    The sound is received by ultrasonic receiver transducer. It converts it to electrical variations

    of the same frequency. These signals are amplified by transistors T3 and T4. The amplified

    signals are then rectified and filtered. The filtered DC voltage is given to inverting pin of op-

    amp IC2. The non- inverting pin of IC2 is connected to a variable DC voltage via preset

    VR2 which determines the threshold value of ultrasonic signal received by receiver for

    operation of relay RL1. The inverted output of IC2 is used to bias transistor T5. When

    transistor T5 conducts, it supplies base bias to transistor T6. When transistor T6 conducts, it

    actuates the relay. The relay can be used to control any electrical or electronic equipment.

    Important hints:

    1. Frequency of ultrasonic sound generated can be varied from 40 to 50 kHz range by

    adjusting VR1. Adjust it for maximum performance.

    2. Ultrasonic sounds are highly directional. So when you are operating the switch the

    ultrasonic transmitter transducer of transmitter should be placed towards ultrasonic receiver

    transducer of receiver circuit for proper functioning.

    3. Use a 9-volt PP3 battery for transmitter. The receiver can be powered from a battery

    eliminator and is always kept in switched on position.

    4. For latch facility use a DPDT relay if you want to switch on and switch off the load. A

    flip-flop can be inserted between IC2 and relay. If you want only an ON-time delay use a

    555 only at output of IC2. The relay will be energised for the required period determined by

    the timing components of 555 monostable multivibrator.

    5. Ultrasonic waves are emitted by many natural sources. Therefore, sometimes, the circuit

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    might get falsely triggered, espically when a flip-flop is used with the circuit, and there is no

    remedy for that.

    Now,In this project we needed to stop the stepper motor when obstacle reflect the waves

    from transmitter,for some period of time and also we want to switch on the alarm(buzzer) for

    the same period.these both processes can be controlled by a relay R1 which further is

    attached with potentiometer which control the time for which stepper motor turn off and

    buzzer turn on.

    Actually to accomplish that we used 2 555-timer,one of which provide the clock pulse

    needed for further operation,and other provide the time for which that clock pulse is allowed

    to move on.

    1.4 CIRCUIT DIAGRAM OF ULTRASONIC RADAR

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    Fig: 1 Circuit Diagram of Ultrasonic Radar

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    1.6 PCB LAYOUT OF ULTRASONIC RADAR

    Fig: 2 PCB Layout

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    CHAPTER 2

    IC USED

    2.1 HEF4017BMSI

    FIG: 3 PIN DIAGRAM OF HEF4017BMSI

    DESCRIPTION

    The HEF4017B is a 5-stage Johnson decade counter with ten spike-free decoded

    active HIGH outputs (Oo to O9), an active LOW output from the most significant flip-flop

    (O5-9), active HIGH and active LOW clock inputs (CP0, CP1) and

    an overriding asynchronous master reset input (MR). The counter is advanced by either a

    LOW to HIGH transition at CP0 while CP1 is LOW or a HIGH to LOW

    transition at CP1 while CP0 is HIGH (see also function table).

    When cascading counters, the O5-9 output, which is LOW while the counter is in

    states 5, 6, 7, 8 and 9, can be used to drive the CP0 input of the next counter. (Oo = O5-9 =

    HIGH; O1 to O9 = LOW) independent of the clock inputs (CP0, CP1). Automatic code

    correction of the counter is provided by an internal circuit: following any illegal code the

    counter returns to a proper counting mode within 11 clock pulses. Schmitt-trigger action in

    the clock input makes the circuit highly tolerant to slower clock rise and fall times.

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    Fig: 4

    Functional Diagram OF HEF4017BMSI

    PINNING

    CP0 clock input (LOW to HIGH triggered)

    CP1 clock input (HIGH to LOW triggered)

    MR master reset input

    O0 to O9 decoded outputs

    O5-9 carry output (active LOW)

    HEF4017BP(N): 16-lead DIL; plastic (SOT38-1)

    HEF4017BD(F): 16-lead DIL; ceramic (cerdip) (SOT74)

    HEF4017BT(D): 16-lead SO; plastic (SOT109-1)

    ( ): Package Designator North America

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    5 STAGE JOHNSON COUNTER

    Fig: 5

    Logic Diagram of 5 STAGE JOHNSON COUNTER

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    Fig: 6

    Function Table

    1. H = HIGH state (the more positive voltage)

    2. L = LOW state (the less positive voltage)

    3. X = state is immaterial

    4. = positive-going transition

    5. = negative-going transition

    Some examples of applications for the HEF4017B are:

    Decade counter with decimal decoding

    1 out of n decoding counter (when cascaded)

    Sequential controller

    Timer.

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    2.2 PIN DIAGRAM OF 555 TIMER IC

    0V

    TRIGGER

    OUTPUT

    RESET

    +Vs

    DISCHARGE

    THRESHOLD

    CONTROL

    top view

    1

    2

    3

    4 5

    6

    7

    8

    555

    IKES0902

    FIG: 7

    555 TIMER IC

    2.4 ASTABLE AND MONOSTABLE GENERATORS THE 555 TIMER:-

    1) THE 555 MONOSTABLE:

    Vin

    Vout

    0V

    C

    R RESET +Vs

    TRIGGER

    DISCHARGE

    THRESHOLD

    OUTPUT

    GND CONTROL

    +Vs

    10nF

    IKES0902

    Fig: 8 555 MONOSTABLE

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    In theory any combination of R and C is possible to achieve a required time period. In

    practice, however, there are several things to remember.1. The transistor connected to the DISCHARGE terminal, as well as having to conduct the

    short-circuit current of the timing capacitor when the monostable resets, also has to carry

    the current flowing through the timing resistor. To prevent destruction of this transistor

    the minimum value of R should be 1k.

    2. The minimum value ofC should be considered as 100pF, since any smaller value will be

    similar to the input capacitance of the timer circuit and so the time periods will be

    inaccurate.

    3. There are two factors to consider when looking at the maximum value of C. The first is

    that any large value capacitors will be electrolytic and so have a leakage current which

    must pass through R. If the leakage current is too large for the value ofRthen the time

    period will be inaccurate. It could well happen, if there is a large leakage current, that

    the voltage across C never reaches 2 3Vsand so the threshold switching voltage level is

    neverreached!

    2) THE 555 ASTABLE

    0V

    C

    RESET

    TRIGGER

    DISCHARGE

    THRESHOLD

    OUTPUT

    GND CONTROL

    10nF

    R1

    R2

    +Vs

    Vout

    +Vs

    IKES0902

    Fig: 9 555 ASTABLE

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    When first switched on the capacitor, C, is discharged and so the voltage across this

    capacitor is less than the TRIGGER voltage and so the output goes to Vs

    . The capacitor, C,

    charges through R1 and R2 until the voltage across C is greater than the THRESHOLD

    switching level, at which point the output voltage becomes 0V and the DISCHARGE

    terminal becomes connected to 0V.

    The capacitor now discharges through R2 until the voltage across C becomes less

    than the TRIGGER switching voltage. When this happens, the output voltage becomes Vs

    and the process repeats. It should be noted that the first pulse is longer than the remainder,

    since C has to charge from 0V and not 13Vs. The same restrictions apply to the values ofC

    and R (R1 and R2) as for the monostable.

    2.3 ULN2803A (DARTINGTON TRANSISTOR ARRAY)

    Description/ordering information

    The ULN2803A is a high-voltage, high-current Darlington transistor array. The deviceconsists of eight npn Darlington pairs that feature high-voltage outputs with common-

    cathode clamp diodes for switching inductive loads. The collector-current rating of each

    Darlington pair is 500 mA. The Darlington pairs may be connected in parallel for higher

    current Capability.

    Applications include relay drivers, hammer drivers, lamp drivers, display drivers (LED and

    gas discharge), line drivers, and logic buffers. The ULN2803A has a 2.7-k series base

    resistor for each Darlington pair for operation directly with TTL or 5-V CMOS devices.

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    fig .pin diagram of ULN2083A

    Logic Diagram

    fig. Logic Diagram

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    fig. Schematic (each Darlington pair)

    CHAPTER-3

    COMPONENTS USED

    3.1 POWER SUPPLY

    1. All electronic circuits need a power source to work.

    2. For electronic circuits made up of transistors and/or ICs, this power source must be a

    DC voltage of a specific value.3. A battery is a common DC voltage source for some types of electronic equipment

    especially portables like cell phones and iPods.

    4. Most non-portable equipment uses power supplies that operate from the AC power.

    Main circuits in most power supplies.

    Fig: 10

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    Power Supply

    DC Power Supply- an Introduction

    In this section we are going to study how the AC mains supply is converted into the DC

    supply required for operating many of the common electronic equipments. As you all may be

    aware almost all of the electronic equipments require DC power supply for their operation.

    Even those equipments to which we provide AC mains supply, convert it internally into DC

    supply to power the electronic circuits

    Fig: 11 dc power supply

    So, almost all electronic circuits require DC power supply and we have AC supply

    commonly available in our homes, offices etc. Now, if we somehow convert the AC mains

    supply to DC, then we can run our equipments using this converted DC supply.

    The process of converting the AC mains supply to DC supply is called rectification and

    the circuit used for this purpose is called rectifier. Using the rectifier circuit and some

    other electronic components one can make a power supply to provide DC power to our

    electronic equipments.

    Let us now see that are those components that together with the rectifier make a complete

    power supply.

    1) Step Down Transformer

    2) Rectifier Circuit

    3) Filter Circuit

    4) Regulator Circuit

    1) Step Down Transformer

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    The step down transformer is used to reduce or step down the mains AC supply voltage to a

    low value. The output from the step down transformer is still in the AC form, only the

    voltage is reduced.

    2) Rectifier Circuit

    In the next section, this reduced AC voltage is fed to a rectifier circuit. The job of this

    rectifier is to convert this AC supply into DC. The output of the rectifier will be a DC

    supply, but it will be a pulsating DC supply, i.e. this DC supply will contain small amount of

    pulses.

    3) Filter Circuit.

    To remove these pulses from the DC supply and to make it a clean DC supply, this pulsating

    DC supply is next fed to a filter circuit. It is the job of this filter circuit to convert this DC

    with pulses into a pure DC.

    4) Regulator Circuit

    This final DC output when given to equipment must provide a constant DC supply. But the

    DC output from the filter circuit changes according to change in the load value or according

    to change in the input AC mains voltage. To keep this DC output constant irrespective of

    change in input AC mains voltage and the load, a circuit known as regulator circuit is used.

    3.2 TESTING & CALIBRATION OF EQUIPMENT

    1) Physical testing

    1) Check front panel.

    2) Check power cord.

    3) Check the cabinet.

    2) Calibration

    1) Analog Voltmeter - For checking analog voltmeter regulated power supply,Digital multimeter is used. The Digital multimeter gives accurate voltage but the

    meter which connected to the equipment not gives proper accurate voltage.

    2) Analog ammeter - For checking analog ammeter regulated power supply,Digital multimeter is used. Power supply points connected to the multi meter then

    connected ammeter series with multimeter output of analog multimeter depend

    upon the scale of analog ammeter.

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    Fig: 13Ammeter

    Fig: 14 Voltmeter of 10 V

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    Fig: 15 Voltmeter of 150 V

    3) Component Checking- All the component like resistance,capacitor,Transistor,

    Diode, Continuity, Voltage, Current measure with the help ofMultimeter

    4) Digital Multimeter

    A meter is a measuring instrument. An ammeter measures current, a voltmeter measures

    the potential difference (voltage) between two points, and an ohmmeter measures

    resistance. A multimeter combines these functions, and possibly some additional ones as

    well, into a single instrument.

    1) Multimeter as a Ammeter

    1. Turn Power Off before connecting multimeter

    2. Break Circuit

    3. Place multimeter in series with circuit

    4. Select highest current setting, turn power on, and work your way down.

    5. Turn power off

    6. Disconnect multimeter.

    7. Reconnect CircuitPOWER

    Ammeter mode measures current in Amperes. To measure current you need to power off the

    circuit, you need to break the circuitso that the ammeter can be connected in series. All the

    current flowing in the circuit must pass through the ammeter. Meters are not supposed to

    alter the behavior of the circuit, so the ammeter must have a very low resistance. The

    diagrams below show the connection of a multimeter to measure current.

    Fig: 16 Multimeter as a Ammeter2) Multimeter as a Voltmeter

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    To use a multimeter as a voltmeter it is connected in parallel between the two points where

    the measurement is to be made. The voltmeter provides a parallel pathway so it needs to be

    of a high resistance to allow as little current flow through it as possible. Voltage

    measurements are the most common measurements. Processing of electronic signals is

    usually thought of in voltage terms. Voltage messurements are easy to do because you do not

    need to change the original circuit you only need to touch the points of interests

    Fig: 17 Multimeter as Voltmeter

    1. Select the DC or AC Volts

    2. If not a auto-ranging mutimeter then start at the highest volts scale and work your way

    down.

    3. Be very careful to not touch any other electronic components within the equipment and

    do not touch the metal tips.

    Multimeter uses

    1. With the help of multimeter we can easily measure resistance

    2. With the help of multimeter we can also measure the forward voltage

    across the diode. With the help of multimeter we alsofind the terminal of transistors.

    Review

    1) A meter capable of checking for voltage, current, and resistance is called a

    multimeter,

    2) As voltage is always relative between two points, a voltage-measuring meter

    ("voltmeter") must be connected to two points in a circuit in order to obtain a good

    reading. Be careful not to touch the bare probe tips together while measuring voltage,

    as this will create a short-circuit!

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    3) Remember to always check for both AC and DC voltage when using a

    multimetercheck for the presence of hazardous voltage on a circuit. Make sure you

    check for voltage between all pair-combinations of conductors, including between

    the individual conductors and ground!

    3.3 LIGHT-EMITTING DIODE (LED)

    3.4

    A LED is a diode made from the semi-conductor material gallium arsenide

    phosphide. Its component outline and symbol are shown below.

    lens

    flat

    cathode

    lead anodelead

    anode

    cathode

    IKES0902

    Fig: 18 Symbol of led

    When forward biased it conducts and emits light of a certain color depending on its

    composition. No light emission occurs in reverse bias and if the reverse voltage exceeds

    approximately 5V then the LED may be damaged.

    R

    +Vs

    0V0VIKES0902

    Fig: 19 Circuit of led

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    A LED requires a series resistor to ensure the current does not exceed its maximum rating,

    which should be taken as 20mA.

    3.4 SEVEN SEGMENT DISPLAY

    a

    b

    c

    d

    e

    f

    g

    IKES0902

    Fig: 20 Seven segment display

    Electronic calculators, clocks, cash registers and measuring instruments often have seven-

    segment LED displays as numerical indicators. Each segment is an LED and by lighting up

    different segments all numbers from 0 to 9 can be displayed. Each segment needs a separate

    current limiting resistor to prevent damage to the segment by excess power dissipation.

    All the cathodes (common cathode type) or all the anodes (common anode type) are joined

    to form a common connection. If the driving circuit is made from transistors, so that the

    seven-segment display segments are connected in the collector circuits, then a common

    anode display will be required

    3.5 STEPPER MOTOR

    A stepper motor is an electromechanical device which converts electrical pulses into

    discrete mechanical movements. The shaft or spindle of a stepper motor rotates in discrete

    step increments when electrical command pulses are applied to it in the proper sequence.

    The motors rotation has several direct relationships to these applied input pulses. The

    sequence of the applied pulses is directly related to the direction of motor shafts rotation.

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    The speed of the motor shafts rotation is directly related to the frequency of the input pulses

    and the length of rotation is directly related to the number of input pulses applied.

    Fig: 21 Fig: 22

    Stepper Motor Poles of Motor

    In addition to being classified by their step angle stepper motors are also classified according

    to frame sizes which correspond to the diameter of the body of the motor. For instance a size

    11 stepper motor has a body diameter of approximately 1.1 inches. Likewise a size 23

    stepper motor has a body diameter of 2.3 inches (58 mm), etc. The body length may

    however, vary from motor to motor within the same frame size classification. As a general

    rule the available torque output from a motor of a particular frame size will increase with

    increased body length.

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    3.6 ULTRASONIC SENSOR

    Ultrasonic sensors (also known as transceivers when they both send and receive)

    work on a principle similar to radar or sonar which evaluate attributes of a target by

    interpreting the echoes from radio or sound waves respectively. Ultrasonic sensors generate

    high frequency sound waves and evaluate the echo which is received back by the sensor.

    Sensors calculate the time interval between sending the signal and receiving the echo to

    determine the distance to an object.

    Fig: 23 Ultrasonic Sensor

    This technology can be used for measuring: wind speed and direction (anemometer),

    fullness of a tank and speed through air or water. For measuring speed or direction a device

    uses multiple detectors and calculates the speed from the relative distances to particulates in

    the air or water. To measure the amount of liquid in a tank, the sensor measures the distance

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    to the surface of the fluid. Further applications include: humidifiers, sonar, medical

    ultrasonography,burglar alarms and non-destructive testing.

    An ultrasonic transducer is a device that converts energy into ultrasound, or sound

    waves above the normal range of human hearing. While technically a dog whistle is an

    ultrasonic transducer that converts mechanical energy in the form of air pressure into

    ultrasonic sound waves, the term is more apt to be used to refer to piezoelectric transducers

    that convert electrical energy into sound. Piezoelectric crystals have the property of changing

    size when a voltage is applied, thus applying an alternating current(AC) across them causes

    them to oscillate at very high frequencies, thus producing very high frequency sound waves.

    Systems typically use a transducer which generates sound waves in the ultrasonic

    range, above 18,000 hertz, by turning electrical energy into sound, then upon receiving the

    echo turn the sound waves into electrical energy which can be measured and displayed.

    The technology is limited by the shapes of surfaces and the density or consistency of

    the material. For example foam on the surface of a fluid in a tank could distort a reading.

    3.7 LM78XX (SERIES VOLTAGE REGULATORS)

    GENERAL DESCRIPTION

    The LM78XX series of three terminal regulators is available with several fixed

    output voltages making them useful in a wide range of applications. One of these is local on

    card

    regulation, eliminating the distribution problems associated with single point regulation. The

    voltages available allow these regulators to be used in logic systems, instrumentation, HiFi,

    and other solid state electronic equipment. Although designed primarily as fixed voltage

    regulators these devices can be used with external components to obtain adjustable voltages

    and currents.

    The LM78XX series is available in an aluminum TO-3 package which will allow

    over 1.0A load current if adequate heat sinking is provided. Current limiting is included to

    limit the peak output current to a safe value. Safe area protection for the output transistor is

    provided to limit internal power dissipation. If internal power dissipation becomes too high

    for the heat sinking provided, the thermal shutdown circuit takes over preventing the IC from

    overheating.

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    Considerable effort was expanded to make the LM78XX series of regulators easy to

    use and minimize the number of external components. It is not necessary to bypass the

    output, although this does improve transient response. Input bypassing is needed only if the

    regulator is located far from the filter capacitor of the power supply. For output voltage other

    than 5V, 12V and 15V the LM117 series provides an output voltage range from 1.2V to

    57V.

    3.10.2 Features

    1.Output current in excess of 1A

    2.Internal thermal overload protection

    3.No external components required

    4.Output transistor safe area protection

    5.Internal short circuit current limit

    6.Available in the aluminum TO-3 package

    Voltage Range

    LM7805C 5V

    LM7812C 12V

    LM7815C 15V

    Connection diagram:

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    Fig: 24 TO-220(T),TO-3(k)

    Selecting the Best Regulator For Your Application:

    The best choice for a specific application can be determined by evaluating the

    requirements such as:

    Maximum Load Current

    Type of Input Voltage Source (Battery or AC)

    Output Voltage Precision (Tolerance)

    Quiescent (Idling) Current

    Special Features (Shutdown Pin, Error Flag, etc.)

    3.8 PCB LAYOUT

    Printed Circuit Boards (PCB) are used to both mechanically support and electrically

    connect electronic components by either surface mount (SMT) or though hole assembly

    using conductive pathways, or traces, etched from copper sheets laminated onto a non-

    conductive substrate.

    Alternative names are:

    Printed wiring board's (PWB)

    Etched wiring boardSwitchboard

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    After populating the board with electronic components, a printed circuit assembly

    (PCBA) is formed. This PCBA subassembly will become an integral layer in a GGI

    manufactured User Interface Assembly.

    Fig: 25

    PCB Layout

    3.9 RESISTORS

    Resistors determine the flow of current in an electrical circuit. Where there is high

    resistance in a circuit the flow of current is small, where the resistance is low the flow of

    current is large. Resistance, voltage and current are connected in an electrical circuit

    by Ohms Law.

    Resistors are used for regulating current and they resist the current flow and theextent to which they do this is measured in ohms (). Resistors are found in almost every

    electronic circuit.

    The most common type of resistor consists of a small ceramic (clay) tube covered

    partially by a conducting carbon film. The composition of the carbon determines how much

    current can pass through.

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    Resistors are too small to have numbers printed on them and so they are marked with

    a number of coloured bands. Each colour stands for a number. Three colour bands show the

    resistors value in ohms and the fourth shows tolerance. Resistors can never be made to a

    precise value and the tolerance band (the fourth band) tells us, using a percentage, how close

    the resistor is to its coded value.

    Resistor

    Fig: 26

    RESISTOR COLOUR CODING

    The resistorcolor code is a long standing standard in both the electronics and

    electrical industries, indicating the value ofresistance of a resistor. Resistance is measured

    in ohms and there is a foundation for it called Ohm's Law. (Want to know about Ohm's Law?

    If so, Each color band represents a number and the order of the color band will represent a

    number value. The first 2 color bands indicate a number. The 3rd color band indicates the

    multiplier or in other words the number of zeros. The fourth band indicates the tolerance of

    the resistor+/- 20%, 10% or 5%. In most cases, there are 4 color bands. However, certain

    precision resistors have 5 bands or have the values written on them, refining the tolerance

    value even more. There is no standard (TANS) however, for the 5th band. From one

    manufacturing company to another, the 5th band may indicate 2%, 1%, 1/2% or even closer,

    according to their own standards. Color bands are usually found on resistors that have a

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    wattage value of 1/8 to 2 watts; though it is rare, there are some 5 watt resistors that are

    banded. There are also some capacitors that are color coded.

    Colour Coding

    Fig: 27

    COLOUR CODING TABLE

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    Fig: 28 COLOUR CODING TABLE

    3.10 TRANSISTORS

    A transistor is a semiconductordevice used to amplify and switch electronic signals

    and power. It is composed of a semiconductor material with at least three terminals for

    connection to an external circuit. A voltage or current applied to one pair of the transistor's

    terminals changes the current flowing through another pair of terminals. Because the

    controlled (output)powercan be much more than the controlling (input) power, a transistor

    can amplify a signal. Today, some transistors are packaged individually, but many more are

    found embedded in integrated circuits.

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    The transistor is the fundamental building block of modern electronic devices, and is

    ubiquitous in modern electronic systems. Following its release in the early 1950s the

    transistor revolutionized the field of electronics, and paved the way for smaller and

    cheaperradios, calculators, and computers, among other things.

    Fig:29 Transistor

    The essential usefulness of a transistor comes from its ability to use a small signal

    applied between one pair of its terminals to control a much larger signal at another pair of

    terminals. This property is called gain. A transistor can control its output in proportion to the

    input signal; that is, it can act as an amplifier. Alternatively, the transistor can be used to turn

    current on or off in a circuit as an electrically controlled switch, where the amount of current

    is determined by other circuit elements.

    There are two types of transistors, which have slight differences in how they are used

    in a circuit. A bipolar transistor has terminals labeled base, collector, and emitter. A small

    current at the base terminal (that is, flowing from the base to the emitter) can control or

    switch a much larger current between the collector and emitter terminals. For a field-effect

    transistor, the terminals are labeled gate, source, and drain, and a voltage at the gate can

    control a current between source and drain.

    The image to the right represents a typical bipolar transistor in a circuit. Charge will

    flow between emitter and collector terminals depending on the current in the base. Since

    internally the base and emitter connections behave like a semiconductor diode, a voltage

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    drop develops between base and emitter while the base current exists. The amount of this

    voltage depends on the material the transistor is made from, and is referred to as VBE.

    Fig: 30 Symbol Of Transistor

    3.11 CAPACITORS

    Capacitors are components that are used to store an electrical charge and are used in

    timer circuits. A capacitor may be used with a resistor to produce a timer. Sometimes

    capacitors are used to smooth a current in a circuit as they can prevent false triggering of

    other components such as relays. When power is supplied to a circuit that includes a

    capacitor - the capacitor charges up. When power is turned off the capacitor discharges its

    electrical charge slowly.

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    Fig: 31 Capacitor

    A capacitor is composed of two conductors separated by an insulating material called

    a DIELECTRIC. The dielectric can be paper, plastic film, ceramic, air or a vacuum. The

    plates can be aluminum discs, aluminum foil or a thin film of metal applied to opposite sides

    of a solid dielectric. The CONDUCTOR - DIELECTRIC - CONDUCTOR sandwich can be

    rolled into a cylinder or left flat

    Fig:32

    Types of capacitors

    Electrolytic capacitors are polarized which means they have a positive and negative

    lead and must be positioned in a circuit the right way round (the positive lead must go to the

    positive side of the circuit). They also have a much higher capacitance than non-electrolytic

    capacitors.

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    Non-electrolytic capacitors usually have a lower capacitance. They are not polarized

    (do not have a positive and negative lead) and can be placed anyway round in a circuit.

    They are normally used to smooth a current in a circuit.

    Fig: 33 Symbols of Capacitor

    CAPACITOR CODING:

    There is a three digit code printed on a ceramic capacitor specifying its value. The

    first two digits are the two significant figures and the third digit is a base 10 multiplier. The

    value is given inpicofarads(pF). A letter suffix indicates the tolerance.

    C 0.25 pF M 20%

    D 0.5 pF P +100 0%

    J 5% Y 20 +50%

    K 10% Z 20 + 80%

    Fig: 34 coding in capacitor

    Example: a label of "104K" indicates 10104 pF = 100,000 pF = 100 nF = 0.1 F 10%

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    Fig: 35 105k capacitor

    3.12 IC SOCKET

    Socketing expensive ICs or holding the firmware during the debugging phase of a

    new design is not only advisable, for most applications mandatory. The Adapters.com sales

    staff has over 50 years combined experience working with IC packaging and there

    applications. In some cases we know the product better than the manufactures themselves. It

    is mainly used for IC safety.

    IC Socket

    Fig: 36

    3.13 RELAY

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    Fig.37 Relays

    A simple electromagnetic relay consists of a coilof wire wrapped around asoft iron core, an

    iron yoke which provides a low reluctancepath for magnetic flux, a movable iron armature,

    and one or more sets of contacts (there are two in the relay pictured). The armature is hinged

    to the yoke and mechanically linked to one or more sets of moving contacts. It is held in

    place by a spring so that when the relay is de-energized there is an air gap in the magnetic

    circuit. In this condition, one of the two sets of contacts in the relay pictured is closed, and

    the other set is open. Other relays may have more or fewer sets of contacts depending on

    their function. The relay in the picture also has a wire connecting the armature to the yoke.

    This ensures continuity of the circuit between the moving contacts on the armature, and the

    circuit track on theprinted circuit board(PCB) via the yoke, which is soldered to the PCB.

    When an electric currentis passed through the coil it generates a magnetic field that activates

    the armature, and the consequent movement of the movable contact(s) either makes or

    breaks (depending upon construction) a connection with a fixed contact. If the set of contacts

    was closed when the relay was de-energized, then the movement opens the contacts and

    breaks the connection, and vice versa if the contacts were open. When the current to the coilis switched off, the armature is returned by a force, approximately half as strong as the

    magnetic force, to its relaxed position. Usually this force is provided by a spring, but gravity

    is also used commonly in industrial motor starters. Most relays are manufactured to operate

    quickly. In a low-voltage application this reduces noise; in a high voltage or current

    application it reducesarcing.

    When the coil is energized with direct current, a diode is often placed across the coil to

    dissipate the energy from the collapsing magnetic field at deactivation, which would

    otherwise generate a voltage spike dangerous to semiconductorcircuit components. Some

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    automotive relays include a diode inside the relay case. Alternatively, a contact protection

    network consisting of a capacitor and resistor in series (snubbercircuit) may absorb the

    surge. If the coil is designed to be energized withalternating current(AC), a small copper

    "shading ring" can be crimped to the end of the solenoid, creating a small out-of-phase

    current which increases the minimum pull on the armature during the AC cycle. [1]

    A solid-state relay uses a thyristoror other solid-state switching device, activated by the

    control signal, to switch the controlled load, instead of a solenoid. An optocoupler(a light-

    emitting diode (LED) coupled with aphoto transistor) can be used to isolate control and

    controlled circuits.

    Fig.38 Circuit symbols of relays.

    (C denotes the common terminal in SPDT and DPDT types.)

    Since relays areswitches, the terminology applied to switches is also applied to relays; a

    relay switches one or more poles, each of whose contacts can be thrown by energizing the

    coil in one of three ways:

    1. Normally-open (NO) contacts connect the circuit when the relay is activated; the

    circuit is disconnected when the relay is inactive. It is also called aForm A contact or

    "make" contact. NO contacts may also be distinguished as "early-make" orNOEM,

    which means that the contacts close before the button or switch is fully engaged.

    2. Normally-closed (NC) contacts disconnect the circuit when the relay is activated; the

    circuit is connected when the relay is inactive. It is also called a Form B contact or"break" contact. NC contacts may also be distinguished as "late-break" orNCLB,

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    which means that the contacts stay closed until the button or switch is fully

    disengaged.

    3. Change-over (CO), or double-throw (DT), contacts control two circuits: one

    normally-open contact and one normally-closed contact with a common terminal. It

    is also called a Form C contact or "transfer" contact ("break before make"). If this

    type of contact utilizes a "make before break" functionality, then it is called a Form

    D contact.

    The following designations are commonly encountered:

    1. SPST Single Pole Single Throw. These have two terminals which can be connected

    or disconnected. Including two for the coil, such a relay has four terminals in total. It

    is ambiguous whether the pole is normally open or normally closed. The terminology

    "SPNO" and "SPNC" is sometimes used to resolve the ambiguity.

    2. SPDT Single Pole Double Throw. A common terminal connects to either of two

    others. Including two for the coil, such a relay has five terminals in total.

    3. DPST Double Pole Single Throw. These have two pairs of terminals. Equivalent to

    two SPST switches or relays actuated by a single coil. Including two for the coil,

    such a relay has six terminals in total. The poles may be Form A or Form B (or one

    of each).

    4. DPDT Double Pole Double Throw. These have two rows of change-over terminals.

    Equivalent to two SPDT switches or relays actuated by a single coil. Such a relay has

    eight terminals, including the coil.

    The "S" or "D" may be replaced with a number, indicating multiple switches connected

    to a single actuator. For example 4PDT indicates a four pole double throw relay (with 12

    terminals).

    EN 50005 are among applicable standards for relay terminal numbering; a typical EN

    50005-compliant SPDT relay's terminals would be numbered 11, 12, 14, A1 and A2 for

    the C, NC, NO, and coil connections, respectively.

    CHAPTER-4

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    TOOLS USED

    4.1 SOLDERING IRON

    A soldering iron is a hand tool most commonly used in soldering. It supplies heat to

    melt the solderso that it can flow into the joint between two workpieces.

    A soldering iron is composed of a heated metal tip and an insulated handle. Heating

    is often achieved electrically, by passing an electric current (supplied through an electrical

    cord or battery cables) through the resistive material of a heating element. Another heating

    method includes combustion of a suitable gas, which can either be delivered through a tank

    mounted on the iron (flameless), or through an external flame.

    Less common uses includepyrography (burning designs into wood) and plastic

    welding.

    Soldering irons are most often used for installation, repairs, and limited production

    work. High-volume production lines use other soldering methods.

    Soldering Iron

    Fig: 37

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    4.2 SOLDERING STAND

    A soldering iron stand keeps the iron away from flammable materials, and often

    also comes with a cellulose sponge and flux pot for cleaning the tip. Some soldering

    irons for continuous and professional use come as part of a soldering station, which

    allows the exact temperature of the tip to be adjusted, kept constant, and sometimes

    displayed.

    Soldering Stand

    Fig: 38

    4.3 SOLDER WIRE

    Solder is a fusible metal alloy used to join together metal workpieces and having a

    melting point below that of the workpiece(s).

    Soft solder is what is most often thought of when solder or soldering are mentioned

    and it typically has a melting range of 90 to 450 C (190 to 840 F). It is commonly used

    in electronics andplumbing. Alloys that melt between 180 and 190 C (360 and 370 F) are

    the most commonly used. By definition, using alloys with melting point above 450

    C (840 F) is called 'hard soldering', 'silver soldering' orbrazing. Soft solder can contain

    lead and/orflux but in many applications lead free solder is used. Perhaps the most commonand most familiar form of solder is as a wire or rod, though plumbers often use bars of solder

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    whilejewelers often use solder in thin sheets which they cut into snippets. Solder can also

    come in a paste or as a preformed foil shaped to match the workpiece. The word solder

    comes from the Middle English word soudur, via Old French solduree and soulder, from

    the Latin solidare, meaning "to make solid".

    Eutectic alloys melt at a single temperature. Non-eutectic alloys have markedly

    different solidus and liquidus temperature, and within that range they exist as a paste of solid

    particles in a melt of the lower-melting phase. The pasty state causes some problems during

    handling; it can however be exploited as it allows molding of the solder during cooling, e.g.

    for ensuring watertight joint of pipes, resulting in a so called 'wiped joint'.

    With the reduction of the size of circuit board features, the size of interconnects

    shrinks as well. At such current densities the Sn63Pb37 solder balls form hillocks on the

    anode side and voids on the cathode side; the increased content of lead on the anode side

    suggests lead is the primary migrating species.

    .

    Fig: 39

    Soldering wire

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    CHAPTER-5

    PRINTED CIRCUIT BOARD (PCB)

    5.1 CLEANING

    When burnt flux and oxidized material begin to accumulate on the tip, they can block

    heat transfer and contaminate joints, making soldering difficult or impossible. Therefore, the

    tips are periodically cleaned. Many soldering stations come with cellulose sponges which are

    dampened and used to wipe a hot iron's tip clean. A wire brush, preferably brass or wire

    wheel (mounted on a bench grinder), is sometimes carefully used to remove very severe

    oxidation, though this may risk damaging the tip's protective iron plating. A small amount of

    fresh solder is usually then applied to the clean tip in a process called tinning. The working

    surface of the tip is usually kept tinned (coated with wet solder) to minimize oxidation.

    Oxidation blocks heat transfer, corrodes the tip, and contaminates the joint.

    5.2 TIPS

    Some soldering irons have interchangeable tips, also known as bits that vary in size

    and shape for different types of work. Pyramid tips with a triangular flat face and chisel tips

    with a wide flat face are useful for soldering sheet metal. Fine conical or tapered chisel tips

    are typically used for electronics work.

    Older and very cheap irons typically use a bare copper tip, which is shaped with a file

    or sandpaper. This dissolves gradually into the solder, suffering pitting and erosion of the

    shape. Copper tips are sometimes filed when worn down. Iron-plated copper tips have

    become increasingly popular since the 1980s. Because iron is not readily dissolved by

    molten solder, the plated tip is more durable than a bare copper one. This is especially

    important when working at the higher temperatures needed for modern lead-free solders.

    Solid iron and steel tips are seldom used because they store less heat, and rusting can break

    the heating element.

    5.3 PCB PREPARATION

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    1. CLEANING OF PCB- The plate of copper is generally washed so as to remove an oxide

    grease or dirt.

    2. DESINGNING- Draw the layout of the circuit on the graph paper. The distance for the

    component is left by placing the component.

    3. PAINTING- Once the layout circuit is drawn, we will paint the PCB. Draw lines on PCB

    with the help of brush. Lines should neither be too narrow nor be too wide.

    4. ETCHING- For etching of the plates take a utensil and wash it properly. For washing

    PCB take water, just enough to complete immerse the board. Add 230 gm of ferric chloride

    carefullywithout splashing andplace the PCB. Place the plate in utensil with the copper side

    up such that the copper side is completely immersed in solution. After sometime the copper

    side etches and the base material could not thus, the etching process is completed.

    5. DRILLING - When the paint is dry, we should drill the plate. The holes should be

    exactly placed so that the component fix exactly in the holes without any bending of leads.

    For the drilling of holes, place it on the proper position. Always ensure that the copper lines

    passage near the holes.

    6. WASHING - The paint of pattern is removed by rubbing it with rag to see the entire

    copper pattern. Now wash the PCB in water.

    5.4 TESTING

    5.4.1 BREADBOARD TESTING

    Each board needs to ensure that the required connection exists, that there are not

    short circuit and drill holes are properly placed. The testing usually consists of visual

    inspection and continuity testing, Complex board requires both.

    5.4.2 VISUALIZATION TESTING

    All the components have been mounted we inspect that they have been mounted

    according to the layout and circuit diagram. Then soldering is done. The circuit is then

    checked for any soldering defects or short circuiting.

    5.4.3 OVERHEATING TESTING

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    The circuit is switched on and then kept on for several hours to check for burning of

    any component especially IC. This helps us to know the consistency of the circuit.

    CHAPTER 7

    CONCLUSION

    This project aimed at reception of ultrasonic signals which are continuously being

    transmitted when something interrupts.

    The project was completed successfully and it was helpful to us in various direct and indirect

    ways, like understanding of circuits as well as procedure followed in manufacturing acomponents.

    A good insight into inspection and Quality check of products helped us to be more familiar

    with the Electronics Industry.

    Conclusion of minor project ULTRASONIC RADAR helped a lot in implementing our

    theoretical knowledge to an practical exposure.

    FUTURE SCOPE:-

    Although the project aimed only at making call through ultrasonic radar but itsimplementations and applications are vast. Ultrasonic Radar can be made of use in:-

    1. Security Alarms

    2. Anti-theft Cars

    3. Missile Launching

    4. Detection of Enemies

    5. Air Traffic Control

    6. Defence

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    CHAPTER 8

    REFERENCES

    1. Digital electronics-R.P.Jain.

    2. Electronics devices and circuits-Sanjeev Gupta.

    3. Digital electronics-Floyd.

    4. http://www. wikepedia.org/ultrasonic_radar

    5. http://www.circuitstoday.com/200m-fm-transmitter/

    6. http://www.members.tripod.com/~transmitters/

    7. http://www.circuitstoday.com/200m-fm-transmitter/8. http://www.members.tripod.com/~transmitters/

    58

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