Bel 714sg

PREFACE With the ongoing revolution in electronic & communication where innovations are taking at the blink of eye, it is impossible to keep the pace with the emerging trends. Excellence is an attitude that whole of human race is born with. It is the environment that makes sure that whether the result of this attitude is visible or otherwise. A well planned, properly executed and evaluated industrial training helps a lot in including a professional attitude. It provides a linkage b/w the student and industry to develop an awareness of industrial approach to problem solving, based on broad understanding of process and mode of operation of organization. During this period, the student gets the real experience for working in the actual industry environment. Most of the theoretical knowledge that has been gained during the course of their studies is put to test here. Apart from this the student gets an opportunity to learn the latest technology, which is immensely helps in them in building their carrier. I had the opportunity to have a real experience on many ventures, which increased my sphere of knowledge to great extent. I got a chance to learn many new technologies and was also interfaced to many instruments. And all this credit goes to organization Bharat Electronics Ltd.

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ACKNOWLEDGEMENT

For an Engineer it’s very important to have proper matching between theoretical knowledge gained from the books and the practical knowledge. Although an engineer can only be successful through sheer hard work but the contribution of his teachers and all those who have been helpful cannot be overlooked. It is a great experience for me to work with the cooperative staff of BEL, PANCHKULA. Through the acknowledgement I would like to pay my profound gratefulness and express my indebtedness to the esteemed personnel, which whole heartedly helped me from the start of my training up to its end. First of all I would like to thank Mr. Anish Chauhan (HRD Manager), who has been so kind and generous to give me so much of his precious time to mark a beginning of my future. I also take the opportunity to thank Mr.Gurwinder Singh (Training and Placement Coordinator) without whom this training would have not been possible. I am sure that the knowledge gained by me during the training would greatly help me in becoming a successful engineer.

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CONTENTS  OVER VIEW OF BEL  Manufacturing units of BEL.  Mission & Objective of BEL.  Various Deptt. Of BEL, Panchkula.  Products of BEL, Panchkula.  PROJECTS UNDERTAKEN  CNR (Composite net radio)  SDA (Secure data adapter)  SECTEL(Secure telephone)  HUD (Head up display)  LUP-291  BEACON MK-3  SMILE  RADAR-BHARANI  ADVANCED MANUFACTURING FACILITY(AMF)  SMT LINE  WAVE SOLDERING MACHINE  TESTING & INSPECTION  PCB LEVEL TESTING  IN CHIP TESTER  FLYING PROBE TESTER  OTHER TESTS  CONCLUSION

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OVERVIEW OF BHARAT ELECTRONICS LTD. Bharat Electronics Limited (BEL) (BSE: 500049, NSE: BEL) is a stateowned electronics company with about nine factories, and few regional offices in India. It is owned by the Indian Government & primarily manufactures advanced electronic products for the Indian Armed Forces.BEL is one of the eight PSUs under Ministry of Defence, Government Of India. It has even earned the government's Navratna status. Bharat Electronics Ltd (BEL) was set up in 1954 (Bangalore) with the vision of attaining self reliance in defence electronics. Starting with manufacture of a few trans-receiver at Bangalore, BEL now make a wide range of hi-tech products like Radar,Sonar,defence communication equipments, components, electronic voting machine, electronics welfare system and various optoelectronics system .Its manufacturing units as well as its offices and services centers spread across the whole country. BEL was primarily set up to diversity in a highly competitive market place, the company has also diversified into areas of civilian need .Some of the successful civilian products include the Electronic Voting Machine (EVM), Solar Power LED based traffic lights broadcast equipments foe DD .Air and telephone equipment for DOT,BSNL and set top box are the latest civilian offering from BEL. Company has laying great emphasis on research and development right from the early years. It has also been able to successful partner as production agency with DRDO. Another thrust area of the company has been the QUALITY. All units of BEL are ISO 9001, 2000 certified as testimony to BEL quality standards the company has received self certification status from DGQA for various product. Mainly, BEL has 95 to 98 percent of its business with government organizations as well as with ministry of defence (Air force, Army, Navy), paramilitary forces, ISRO and various PSU’s.

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MANUFACTURING UNITS OF BEL Currently BEL has 9 different units spread across the country. Among these, Bangalore units established in 1954 is one of the largest units having an area of about 1000 acre. Each unit has its own specialization in various fields of Defence Electronics Equipments. However, the various units are as follow:         

Bangalore (Corporate Head Office) Chennai, Tamilnadu Panchkula (Haryana) Kotdwara Ghaziabad Pune Hyderabad Navi Mumbai Machilipatnam

In addition to these manufacturing units, BEL has the following regional offices:     

Delhi Mumbai Cochin - Product Centre Vishakhapatnam Kolkata

Liaison Office:   

Agra New York City Singapore

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VISION, MISSION, VALUES AND OBJECTIVES  VISION To be a world-class enterprise in professional electronics.  MISSION To be a customer focussed, globally competitive company in defence electronics and in other chosen areas of professional electronics, through quality, technology and innovation.  VALUES  Putting customers first.  Working with transparency, honesty & integrity.  Trusting and respecting individuals.  Fostering team work.  Striving to achieve high employee satisfaction.  Encouraging flexibility & innovation.  Endeavouring to fulfil social responsibilities.  Proud of being a part of the organization.

 OBJECTIVES  To be a customer focussed company providing state-of-the-art products & solutions at competitive prices, meeting the demands of quality, delivery & service.  To generate internal resources for profitable growth.  To attain technological leadership in defence electronics through in-house R&D, partnership with defence/research laboratories & academic institutions.  To give thrust to exports.  To create a facilitating environment for people to realise their full potential through continuous learning & team work.  To give value for money to customers & create wealth for shareholders. 6

 To constantly benchmark company's performance with best-inclass internationally.

DEPARTMENT OF BEL, PANCHKULA BEL, Panchkula established in 1986 has different divisions or departments:         

MKTG/D&E (Marketing division/Development & Engg.) MFG (Manufacturing) MM (Material Management) PA (Product Assurance) QA (Quality Assurance) P&S (Plant & Services) P&A (Plant & ) F&A (Finance & ) QM (Quality Manager)

 HOW THE WHOLE PROCESS TAKES PLACE?  MARKETING: First of all people of marketing i.e. (MKTG Deptt.) approach to their customers (mainly defence forces) and give the demo of latest or new technology. However, if they are satisfy then they give the clearance and order regarding the same product.  CONTRACT REVIEW: Meeting is organized amongst all department heads regarding deciding the target (quantity of products) as well as its specific time span of its completion.  SELL ORDER: 10 digits number are allotted to identify each product uniquely.  DOCUMENTATION: List of sub parts of products is send to the production control Deptt..  PC DEPTT.: Production control department decide the requirement of sub assembly component and give their list to 7

purchase Deptt.. Usually the purchasing cycle is of longer time span.  Purchase Deptt.: In order to import the items from other countries.  Subcontract Deptt.: For purchasing the local products like screws, washer’s etc purchasing Deptt. require some time span, in order to meet the requirement of production control Deptt.. It may be of 10-20days or up to 3 to 4 months (in case of importing the components).After this PC Deptt., issue the material in small batches (in order to avoid the misuse of components which is very precious and costly).In this way, by achieving the smaller target the whole of the huge target is achieved within the specific time period.  MANUFACTURING DEPTT.. : Finally the assembly of the product takes place within the advance manufacturing Deptt..  TESTING: Testing of whole of the product take place.  QUALITY CONTROL: Quality Control Deptt.. Check the quality of product obtained. However, customer may also be involved at this stage.  FGS: Finished Goods Store, from where product gets dispatch after cutting down out bond delivery (OBD).

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PRODUCTS OF BEL, PANCHKULA The Panchkula unit of the company is inclined towards the defence equipments related to communication. So, most of the products of BEL-Panchkula are defence communication equipments. This includes:         

CNR (Composite Net Radio) SDA (Secure Data Adapter) SECTEL(Secure telephone) HUD (Head Up Display) LUP-291 (Secure Hand Held UHF Radio) BEACON MK-3 SMILE (Secure Multi Interface Link Encrypter) SEED STARS-V

LATEST PRODUCT DEVELOPMENT:  Low Level Light- weight Surveillance Radar Bharani.

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PRODUCTS OF BEL, PANCHKULA

CNR (COMPOSITE NET RADIO)  INTODUCTION: CNR radio is a frequency hopping device with inbuilt ECCM (Electronics Counter Count Mechanism) VHF transmitter which works in the frequency band of 30-87.975 MHz and provides secure and reliable voice and data communication gamming environment. The radio set operates in frequency band of 30 MHz to 87.975 MHz at 25 MHz frequency channel spacing 150 Hz squelcher tone or carrier channel spacing operation is possible for comparatively with other radio sets. Critical functionality of internal modules is check by BITE. The radio functions are preset channel with rotary switches, which are fitted with rugged glass fitted Xylon knobs. The radio operates in frequency hopping FF clear mode and FF sec (1) mode RSCNR is inter operatable with STAR-V. The radio also incorporates the states of art features like hailing, emergency, crypto key, erasure, changing , selector calling and scanning.

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CNR CARDS: FRONT CONTROL MODULE: It is primarily responsible for providing the interface to control and functionality of radio. This includes 3*5 matrices keyboard, 16*2 LCD display, and a set of rotary mode selection nail and volume control keys. AUDIO PROCESS CARD: This is built around F*360 LG and F*375 J audio processing chips from CML. The audio input/output signals are interfaced with DSP card. DSP MODULE: The module facility involves software implementation of complex hopping pattern generation, signal processing algorithm for frequency hopping synchronization, error control and encryption/decryption. RF MODULE: 10

The main function of RF module is down conversion of receive RF carrier in 30-87.975 MHz to fixed lower IF using fast setting low phase noise frequency hopping synthesize.  SALIENT FEATURES:  Signals channel FM operation in 30-88MHz.  10 Preset channels.  Secure voice and data communication in fixed frequency mode.  Built in test equipment facility.  Remote control.  Secure key selection (32 keys) for interoperation with STAR-V.  TECHNICAL SPECIFICATION OF CNR:  Power supply : 24 VDC  Frequency range : 30.00-87.975 MHz  Channel spacing : 25 KHz  No. of channels : 2320  No. of hopes : 250 Hopes/sec  Modulation : FM  Sync time : 21 sec  Preset channel : 10

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SMILE (SECURE MULTI INTERFACE LINK ENCRYPTER)

 INTRODUCTION: SMILE is a secure multi interface link encryption unit. It has been design to secure bulk data traffic oner point to point based line and radiate with data rates up to 2 Mbps. SMILE is a standalone device with protocol electrical interface that can be configured for various interface available on end equipments like routers ,switches, exchanges and modems. The push button, indicators and connectors are located at the front and rear of the equipments.  SALIENT FEATURES:  2 Mbps (max) data rate is ed.  Data rate can be configured through push button (keypad).  It s synchronous full duplex point to point secure data communication.  It s Multi Interface.  Built in robust, custom development high grade crypto algorithm.  Emergency erasure for key data ed.  2*16 character alphanumeric display.  This encryption algorithm is non error propagation and uses symmetric keys.  This encryption algorithm used is complex enough to withstand sophisticated modern day attacks.  Operate for AC power only and having inbuilt powerful diagnosis feature (BITE).

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BEACON MK-2  INTRODUCTION Beacon MK-2 is a compact full duplex crypto device providing high grade of secrecy for data communication on normal telephone lines (using V.92 modems), T/P networks, RS-232 networks and lan networks (10/100 Mbps).It s both online and offline modes of operation. It is an add on unit connect between a PC resident graphical interface (GUI) software provided with equipments. Connectivity of PC can be through serial port or USB port. Network interface can be through serial port or USB port. Network interface can be selected through GUI software or through front control. It is very easy to install and operate on 24VDC grade encryption algorithm with very use friendly call set up configuration through the PC providing field up giadiability. It incorporates a very robust automated crypto synchronization mechanism, which ensures reliable operation.LCD display and keypad on the front provides interface for configuration key loading network selection and status monitoring.  SALIENT FEATURES:  High grade indigenously designed crypto algorithm.  encryption/Decryption of all type of data file.  Models ed: Offline and Online (secure).  Full duplex transmission with automatic call by call key changed rugged synchronization and re-synchronization.  friendly and customizable key managements.  Keypad and 4*20 characters LCD display to assist in MMI operation.  Prevention for unauthorized access using .  BITE facility to check function of equipment.  Field upgradability of crypto algorithm.  Emergency erasure of crypto algorithm and key data.  Self destruction of equipment in emergency.  Operate with standard 220v, 50Hz AC main power or 24VDC. 13

 Compact and light in weight (less than 5kg).

STAR V MK-2(25W [LUP-275])

 SALIENT FEATURES:  friendly operation of the Radio through keypad and easy to operate rotary.  Frequency band: 30-87.95 MHz  Modes of operation: a) Voice and Data b) Frequency hopping  Clear and secure  Rebroadcast: Voice and Data in FF/FH.  Remote Rebroadcast.  Remote control.  Number of present channel /Hop set: 8Preset channel +1manual channel in FF clear/secure mode and 9 Hop set in FH1/FH2 mode.  Data communication with built in data modem in FF and FH.  Synchronization: Automatic synchronization based on 70 D (Time of the day)  Types of call selection and broadcast.  Selective call: FF secure, FH voice and data. 14

 Scan: Scan and preset channel in fixed frequency, clear mode.  Remote control unit:  This unit allows the radio to operate remotely up to a distance of 2 kms using two make line.  DIMENSIONS: Related to radio LUP-275 alone a) Width: 250+10mm b) Depth: 220+10mm c) Height: 104+10mm d) Weight: Not more than 3.8 kg

 PERMISSSIBLE AMBIENT TEMP: a) Operational : -300C to +550C b) Storage : -400C to +700C

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SECURE UHF HAND HELD RADIO (LUP 291)

 INTRODUCTION The Secure UHF Hand Held Radio (LUP-291) is a light weight and portable trans-receiver. The radio is useful for ground communication at platoon level. The simplex radio operates in UHF frequency band of 403 to 470 MHz The radio provide clear and secure mode of communication. The radio is microprocessor controlled and having clear & secure mode of communication. A 7.2 volt DC source power the radio set from the bottom .  CONTROL, SOCKETS & FUNCTION  ANT: This is used to mount antenna.  PTT: This is a push to talk, by default radio is in received mode but when transmitter mode.  SQ: Squelch key is used to toggle between squelch on and off mode, relevant in carrier mode only.  P (PROGRAM): It has features like preset frequencies, change of , channel with selection, enable/disable, and whisper mode.  B (BITE MODE): This mode tests the health status of modules of radio.  C: Enable cloning of EEPROM data from one radio to another.  F: Enable Loading of data from fillgum/PC.

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 E: Erasure of EEPROM data .Even s the remote erasure which erases data in EEPROM of radio (i.e. distant radio) using another radio set.

CHL SWITCH: Channel switch it enable set of preset and manual channel .The set has four banks with eight preset frequency channel with a selective channel spacing of either 12.5 or 25 KHz.  M: Manual channel, programmable channel is available for communication and this frequency is stored in the memory on power on it is 403 MHz.  1-8: Eight preset frequency channels each in A, B, C and D banks.  S-N: Scan and enable scanning of preset channel of selective banks. Active channel detected is displayed.  MD: 1 during power ON entry.  DSR: 2 during power ON entry.  INC: 3 during power ON entry.  ENT: 4 during power ON entry.  TX/RX LED: Green in RX (receiving) mode and Red in TX (transmission) mode.

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SECTEL (SECURE TELEPHONE)

 INTRODUCTION Secure telephone is a compact, full duplex digital subscriber end secrecy device. It provide higher grade of secrecy in normal telephone line by replacing the subscriber normal telephone instruments. It can operate over standard voice channel of telephone network link Dot single line circuit and STD circuits. It operate from 230 VAC main using AC-DC adapter. Speech is digitalized using linear predictive coding (LPC) technique and is digitally encrypted by high complex crypto algorithm which ensures high grade secrecy. At the receiver end encrypted data stream us demonstrated S/W clear and secure mode during the same call. It can also save up to 10 telephone numbers of 15 digit length in its memory.  SALIENT FEATURES: 18

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High grade speech secrecy. Full duplex transmission in secure and clear modes. Data rate 2.4 kbps full duplex. Memory dialing of 10 stored numbers. 2*16 character LCD display to show the status.

SDA (SECURE DATA ADAPTER)  INTRODUCTION The USB thumb encryption is designed to secure data that is sent over any wired and wireless communication media or transported using any portable storage device. The Encrypter is a compact USB powered state of art technology encryption USB interface which can be connected to USB port of PC/Laptops. The data inputs from PC/Laptops are encrypted using a higher grade properly encryption algorithm. The encryption device incorporates security mechanism to guard not only the threats of overlapping but unauthorized usage. Encryption key are loaded into encryption using either fillgum or through several parts of PC/Laptop.  SALIENT FEATURES:  Serve for transmission over wired and wireless communication.  A key is required to encrypt or decrypt the data.  Porting of indigenously designed high grade encryption algorithm.

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RADAR BHARANI Low Level Light-Weight Radar (LLLR), is a L-Band, 2D, light weight, battery powered and compact sensor which provides 2D surveillance solution to alert Army Air Defence Weapon Systems mainly in mountainous terrain against hostile aerial targets like UAVs, RPVs, hovering helicopters and fixed wing aircraft flying at low and medium altitudes . SALIENT FEATURES :  

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L-Band 2D Surveillance of aerial targets flying at low and medium altitudes. Automatic detection and tracking of: - Fixed wing aircrafts - Helicopter - UAVs Detection of hovering Helicopters Target designation and distribution to Weapon Sites and Command Centre. Integrated IFF Easily transportable by men, animal transport, etc Net equipment weight: < 150 kg excluding Power Source Easy portability with each load: < 30 kg Highly modular for quick setup Remote operation and radar display through the Commander Display Unit (CDU) Separation of CDU from sensor head: 750 m

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ADVANCED MANUFACTURING FACILITY (AMF) Advanced manufacturing facility uses the surface mounting technology (SMT) for mounting the reeled components on the surface of PCB, while leaded (Through hole) components are placed manually on its surface. So, in order to carry out the whole process of placing the reeled component on PCB surface, various fully automated machines is used in sequential order which is known as SMT line.  SMT LINE: SMT Line involves the various stages which work in proper sequential manner. The stages involve are as follow:  LOADER: First stage of the SMT line includes the process of loading. In this case called “MAGZINE” is loaded with PCB’s on which component has to be mounted. This loading is done manually on magazine.  STENCIL PRINTER: In this stage solder paste is applied on PCB’s in order to affix the component on its surface. Solder paste is the mixture of Tin(67%)Lead(33%) alloy having the melting point of 1830C.However the thickness of paste is totally depend upon velocity as well as the pressure adjustment of squeeze over the surface of screen having aperture same as 21

that of PCB design. Before applying the paste, the Fuducial (reference point) of PCB should be matched with respect to screen in order to avoid offset.  PICK & PLACE MACHINE: It is consider as the heart of the SMT line. It picks up the reeled component from feeder and places them on the predefined or correct position of components on surface of PCB. However the X-Y-Z position of components is specified with respect to its centroid in program set of the instrument with the help of PCB camera. There are two Pick and Place Machine:  MY DATA P&P machine: Made by Sweden, having the capacity of 24000 H (component per hour).The whole concept of pick and placing of component is based on suction pressure of nozzle. It consist of two heads, one is HYDRA head which consist of 8 nozzle (mean it can pick and place 8 component at a time) and another one is MIDAAS head which consist of one nozzle also known as “master head” because it has the capability to pick large size component.  SIEMENS P&P machine: It has capacity of pick and place17000 H(component per hour) .Similarly, it also consist of two heads i.e. REVOLVING head which have 12 nozzle and another one is RECIPROCATING head which have only 2 nozzle but for large size component same as that of midas head. In case both P&P machine is used at a time, speed of SMT line may reach up to 41000 H approx. Since, BEL mainly design products for defence, so reliability is important concern due to which speed of SMT line is usually slow as compare to another SMT line in various private companies.  REFLOW MACHINE: After ing through P&P machine, the components are placed temporarily on PCB surface. So, in order to make the ts of component permanent w.r.t PCB, it has undergone through reflow machine which consist 12 heaters along which thermocouple are attached in order convert electrical energy into heat energy. This machine consists of 4 different zones as follow: 22

 PREHEAT ZONE: (20 to 30C/sec), bring the liquid state of solder paste into its solidified form.  SOCKING ZONE: Temperature increased up to 1830C, which is the melting point of Tin-Lead alloy mixture. Due to which component is starts floating as a result it get well settled at its original position. In this stage the paste again comes in its liquid form.  REFLOW ZONE: Temperature increased 300 to 400C above its melting point i.e. up to 225 to 2300C due to which paste comes in solidified state which makes the t permanent and solid.  RAPID COOLING: This process includes the rapid cooling of PCB from such higher temperature (2300C) to 400C. So, after ing through all above stages of reflow machine all component get permanently fixed at its appropriate location which leads to maximum reliability of PCB.

 AUTOMATED OPTICAL INSPECTION(AOI): In this stage ,PCB has to undergone through automated inspection with the help of AOI machine, where the main focus of the operator is on detecting the faults like short circuit of pins, excess solder, dry solder, bridging in IC’s, tom stoning as well as missing of component from its appropriate location. Basically, AOI is automated machine in which the camera of 1.3 MP detects each fault on the surface of PCB. Camera radiation detect each and every component three times however if some fault detected, it will immediately discard the PCB.  X-RAY MACHINE: X-ray machine is used to see or to detect the fault beneath the component. Since PCB is multilayered board, so probability of fault in its deg is more. Hence X-rays are used which get penetrated through each and every component or even through board also in order to detect any fault. However, if at any location it gets reflected back indicates the presence of fault at that location. Basically, the X-ray machine used to detect the fault

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in BGA (Ball Grid Array) and POP (Package on Package) types of components.

SMT LINE

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WAVE SOLDERING MACHINE

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Wave soldering machine consists of the PCB carrier stand, which can hold 10 PCBs at a time. This stand moves over the conveyer belt whose speed is 60 – 80 cm/sec. The flux used for soldering is Rosion R8. The thinner is added to the flux so as to make the flux thinner. The next component in this machine is air knife where the excess flux is removed. Next comes the pre-heater zone. It consists of 6 per-heaters. The temperature for the first 2 heaters is 100 degree Celsius, for next two pre-heaters the temperature is 140 degree Celsius, and the temperature for last two chambers is 180 degree Celsius. The box containing the solder is called the solder bath, which has the capacity of 400kg. The temperature of the solder bath is 250 – 270 degree Celsius. While the solder is heated up inside the solder bath, the pump arrangement provides for the hot solder to flow. The solder nozzle then produces a solder wave. After the solder bath, the conveyor belt is set on the angle of 4 – 7 degrees. This machine costs around 30 lakhs. This machine also consists of the sensors which sense the green mask as well as the spot mask on the PCB such that the solder does not stays on it. The waste material of the machine is known as dross. The solder temperature is continuously controlled by the PID controller and its thermo couples. In short, the description of the process is as follows: To arrest the air pollution by fume emission from wave soldering machine.

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WAVE SOLDERING MACHINE AND ITS ADVANTAGES

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TESTING AND INSPECTION It is a very important stage in production of any stage module. Hence various specifications which a product has to give to a customer are checked. Basically, the testing is done at two main stages, namely:  PCB level testing.  Main testing.  PCB LEVEL TESTING: PCB level testing is conducted at various levels. In this, first of all the PCB is placed in chamber with temperature varying from -300 to +700C.This is done in order to check the stability of components of PCB. This process is generally done in 80 hours and is known as “Ageing” process. Then we use the various mechanisms to check the PCB. These are: IN CIRCUIT TESTER (ICT): In this a fixture of PCB is first prepared and the PCB is placed on the bed of pins. These pins are used to check various chips or components on the PCB. The relay present below the fixture make and break the circuits. So, all the components are tested quickly.  FLYING PROBE TESTER (FPT): It is recognized in XY plane. But this test is quiet mechanical in nature. In this four phases are used for testing. The PCB which all these test are then sent to assembly unit. In assembly units all the PCB’s are placed to make the finally finished product. Various tests that are conducted as given below: a) Room temperature reading b) Vibration test c) Thermal cycling test d) Leak test e) Short range communication test f) Long range communication test g) PDI (Pre Dispatch Inspection)

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CONCLUSION

The six weeks of summer training at BEL, PKL unit generated a lot more interest in my subject. It made me more aware of the scope of Electronics & Communication Engineering. It has also made me appreciative of an industrial work environment. Undergoing training on the indoor substation has helped me integrate conceptual knowledge with real life application. I was fortunate to have personal guidance from experienced professionals who took been interest in explaining the working details of various equipments. I feel that without this opportunity, my own understanding of this subject and also the motivation to acquire more knowledge would have remained incomplete.

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BIBLIOGRAPHY THE MAIN RESOURCES OF THE WORK WERE THE FACULTY OF HRD DEPARTMENT. THE MAIN WEBSITE:  www.bel-india.com

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