Hacettepe UniversityDepartment of Electrical and Electronics Engineering

Summer Practice Report

Student'sSurname, Name : Artan, ErdemID : 20522044E-Mail : badibere@gmail.comMobile Phone : +90 555 716 62 95

Date : 20.07.2009 – 28.08.2009z

Company'sName : Selex CommunicationsDivision : CommunicationLocation : Ankara-Konya Roadway, 25th Km.

06830 Golbasi / Ankara / TURKEYPhone : +90 312 484 51 81E-Mail : sales@selex-comms.com.tr

Related Field : Production

TABLE OF CONTENT

1. INTRODUCTION 3

2. DESCRIPTION OF THE COMPANY 4

2.1 Company Name 42.2 Company Location 42.3 Organizational Structure of the Company 42.4 History of The Company 42.5 Field of Business 62.6 About Company 8

3. MY ACTIVITIES 9

3.1 First Week 93.2 Second Week 11 3.2.1 Conclusion of First and Second Weeks 123.3 Third Week 13 3.3.1 Conclusion of Third Week 143.4 Fourth Week 15 3.4.1 Conclusion of Fourth Week 173.5 Fifth Week 17 3.5.1 Conclusion of Fifth Week 183.6 Sixth Week 18 3.6.1 Conclusion of Sixth Week 20

4. PROJECTS 20

5. CONCLUSION 54

6. REFERENCES 56

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1. INTRODUCTION

I have performed my summer practice in Selex Communications, which is a company in the

field of defense electronics systems. This was a six weeks practice between 20.07.2009 and

28.08.2009. I performed my work in Production Department.

The summer practices are very important for candidates of engineers, since these are the

times when they have their first experiences about and gain sight into their profession. As a

candidate of engineer, during my summer practice this summer, I was able to experience how to

become an engineer, how things work out for engineers in the real world and the most important,

what is the area I want to gravitate. The aim of my summer practice is to get familiar with work

discipline and organization in a company, learn basically how a company works and more

importantly. Thus, observing the applications of the courses we have preceded in the university, I

was able to evaluate in which area I can proceed or which area is not for my interest. Since the

university education cannot give an engineer all about being an engineer, this summer practice was

also helpful for improving me about how to catch the time and get the information I need. In this

respect, doing my summer practice in SELEX Communications was a real chance for me. Because,

this is a company which develops its technology itself; they make their design, produce their needs

and develop their products. Ongoing, Selex Communications is a partially military foundation so

what it produces will be used for military actions. This makes this company to produce the newest

and the strongest of all. In this sense, I was able to observe what new technologies arouse in the

market.

During my summer practice I had a chance to many electrical and electronics engineers,

their approach to given project and I have involved in especially production section of A400M and

C130 planes and GENESIS project.

Here, in my summer practice report I explained all the activities, in detailed, I have involved

and my observations. The report starts with the description of the company, continues with the

projects I have involved and lasts with conclusion.

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2. DESCRIPTION OF THE COMPANY

2.1 COMPANY'S NAME

Selex Communications

2.2 COMPANY'S LOCATION

Ankara-Konya Roadway, 25th Km, 06830 Golbasi / Ankara / Turkey

2.3 ORGANIZATIONAL STRUCTURE OF THE COMPANY

Management

General Director K. Ekrem Kadioglu

General Director Assistant (selling & marketing) Unal Solay

General Director Assistant (operations) Ayhan Evren

Programming Director Timur Akgul

Director of Financial Operations Mert Yaycioglu

2.4 HISTORY OF THE COMPANY

Selex Communications, since 1989, is a Finmeccanica Company, which states its activities mostly within the telecommunications field, was established to satisfy the need of Turkish Armed Forces by supplying solid state, broadband and high power HF/SSB Transmitters, designed to meet the standards of software programmable radios to satisfy the performance required in the use of HF radios in modern, digital communication systems.

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For this purpose, it has started production in 1992, in Ankara/Golbasi, spread over 36000 m2 area with 4100 m2 closed place.

At first there was MARCONI Communication firm which was an English Company and which was well known by its radiophones. Even now, about Erzurum and Erzincan those Marconi radiophones are being used in armies. After some transactions, there was a new company, named SELEX Communications, which is an originally Italian company. SELEX Communications is a part of SELEX Group firms. In fact, these group firms work also under FINMECCANICA Group companies. Therefore, there is a hierarchy in those companies and firms. They spread all over the world, some of them are just sales offices whereas some others are factories engaging in manufacturing. Generally, FINMACCANICA Group Companies’ interest area is defense industry, more specifically; space, aeronautics, helicopters, defense electronic and information technology, defense system, transportation, and energy. It has 58.059 personnel totally and it also holds powerful finance resources and investment. It embraces many other group firms like SELEX Group Companies which has totally eight offices and factories in England, Germany, Russia, Romania, Turkey, Italy, Brazil and North America. SELEX Communications A.Ş. is the Turkish member of SELEX Group Companies. SELEX Turkey assists ASELSAN, develops and runs projects for Ministry of National Defense. One of those projects is A400M Programme and Lighting Systems Equipment, in sum which is related with Boeing war planes’ lighting studies.

SELEX commonly work on military communications. It has helped and still assisting Aselsan in order to develop Turkish Military Communications. Between 1989 and 1997, it has finished around 3000 Scimitar HF/SSB Radios and delivered them to Turkish Armed Forces. Now, it also continues maintenance, repair and education of these devices which are being used successfully by Land, Naval, Air, Gendarme and Coast Guard.

Selex Communications is included several military projects like: in 1997, it has started Turkish Naval Forces Shore Communication Center Modernization Projects and in 1998 “Dogan” Class Fast Patrol Boat Integrated Communication System Modernization Project. TCG Marti and TCG Volkan Assault Boat Modernization have finished and delivered to Turkish Naval Forces and the third Assault Boat Modernization work is still continues.

The company also meets basic interior and exterior communication needs for naval platforms like Turkish Navy Ships with Totally Integrated Communication Systems Project (TAFICS) which is a branch of the Project “Genesis” that was awarded to the company by Turkish Naval Forces. For this purpose it provides the integration of LF/MF/HF, VHF, UHF radio, message processing, transfer, intercom, alarm, announcement systems. It uses PC based system to get ease in usage and design flexibility, so the changes in needs can easily be configured to the system.

Until today, the company has displayed a wide range of advances communication, navigation and identification solutions for terrestrial, naval, avionic applications in the defense and professional communications markets including its MH-344 ‘LOS Radio Link’ and MT-321 ‘Multichannel Optical Line Termination Unit’ devices production and TETRA (Terrestrial Trunked Radio) Project which is based on Mobile Radio Networks activities.

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2.5 FIELD OF THE BUSINNESS

Land / Naval / SatelliteIn the land and naval sector, SELEX Communications supplies state of the art

telecommunication systems. The offered solutions are particularly suitable in hostile environments,

such as peace keeping and emergency operations, armed conflicts and other similar situations,

where secure communications are essential to the success of the operation.

Selex offers:

◦ Infrastructure ground systems and networks

◦ Mobile ground systems and networks

◦ Naval systems and networks

◦ Satellite systems and networks

◦ Command and control systems

Avionics:

With a complete portfolio of CNI( Communication, Navigation and Identification) and mission

Support integrated equipment and systems, SELEX Communications offers a wide range of

avionics solutions.

Thanks to its technical and commercial program management capabilities and its continuous

process of technological innovation, SELEX Communications is a partner in many major European

and International.

Selex offers:

◦ Communication

◦ Navigation

◦ Identification

◦ Support of mission

◦ Automatic test equipment

◦ Display & control panel

Security:

SELEX Communications provides telematic network security and connection encryption products,

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physical security solutions, system integration activities, consultancy, outsourcing, evaluation and

security certification services for national and international Defebce organizations, large size firms

and to public or private bodies. The range of products and solutions available can satisfy each type

of need of the major markets, such as Defence organizations, Central public administrations, local

administrations, banking and insurance systems and industry.

Selex offers:

◦ Telematic network security and connection encryption products

◦ Physical security solutions

◦ System integration activities

◦ Consultancy, outsourcing, evaluation and security certification services

Professional Mobile Radio:

Selex Communications activity in Professional Mobile Radio consists of: Mobile Radio

Networks, based on digital networks TETRA (Terrestrial Trunked Radio) and SIMULCAST, both

of them developed in compliance with new ETSI standards; integrated Communications

Menagement System for Communications Control Centers; Air Traffic Control Communications

System (ATC).

SELEX Communications has a great experience in GSM and GSM-R mobile communications and

its offer includes terminal equipment, compact networks and radio coverage solutions. All these

solutions are deigned for organizations, such as Emergency Services, Government bodies,

Transportation and Fleet Management, Public Utility Companies, that require secure and reliable

mobile communications.

Telecommunications Operators:

Selex Communications provides the most advanced fdigital mobile networks for Telecom

Operators. Member of WiMAX Forum, SELEX Communications is able to offer a complete set of

WiMAX-based equipment suitable for all broadband wireless data applications in Civil, Private or

Public Administration sectors, as well as in Military field and as extension of institutional networks

for public safety.

The range of solutions for Telecom Operators includes a GSM-GPRS mobile communication

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system especially designed for Corporates, Shipping Companies, Public Transport services,

communities, campuses or isolated area not reachable by public telephone networks. This system

offers, in a very compact and cost effective solution, the features of a complete mobile radio

network and the potential for tailored and advanced application development

2.7 ABOUT SELEX

2.7.1 Production - Assembly:

In Selex, too many product is produced and also some circuit designs are made. Selex is

commonly work on military communications. Selex gives services from design to production.

Provided production entries (like circuit components) are bought from Turkey, but if these entries

do not locate in Turkey, Selex buy these from abroad.

2.7.2 Maintanance – Supoort / Repair After Sale:

Company gives support and service after sale. So Selex is always ready for maintenance and

repair. Selex also keeps everything about the project in case of necessity.

2.7.3 Research and Development Activities:

Selex gives huge importance on their Research and Development Activities. Selex’s

Research and Development Skills are;

• Optic Designs for Lightning Systems

• Mechanical Designs.

• Electronical Designs

• Buried and Application Software Development

2.7.4 Abroad Partnerships:

As I already mentioned before, Selex is a subcompany of Finmeccanica Company. Abroad

connections and agreements of Selex is directed and guided by Finmeccanica.

2.7.5 Income Sources:

Finished projects, results of research and development activities, system integration are

company’s main income sources. Company budget is determined from Italy because of being

connected to Finmeccanica. Also adding or taking out of staff is guided and directed by Italy.

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2.7.6 Level of Taking Benefit From Computer:

All the design works on the company is made by computer. In circuit design, mechanic

design, optical design, Selex uses very special hardwares and softwares. Inside the company and out

of the company,workers connect themselves via electronic mail. All users each have computer,

internet possibility and office softwares special to themselves. All the computers are connected to a

web. All the files spared day by day, so Selex aims minimum data loss. Total computer number is

about 100.In design operations,some well-known softwares are used. These are;

Electronic Design:

◦ CADENCE ORCAD 10.0◦ ZUKEN

Electronic Material Database:◦ Aspect eXplore 5.0.1.1 – CCDB

Reliability and Perpetuation:◦ RELEX 7.77◦ FRACAS

Mechanical Design - 3D Modelling:◦ Dassault Systemes – CATIA V5.0 R12 - ME2◦ Autodesk Inventor 9

Optical Design:◦ TRACE PRO 3.3◦ SABER V2004.06

3. MY ACTIVITIES

I've been in Selex Communications for 6 weeks period. At this period of time, I have been included many work orders and take part on projects. But especially I worked on A400M cargo plane lightning project and also C130 and GENESIS projects. I worked in production department of Selex Communications.

In first two weeks of my six weeks period in Selex Communications, I worked in quality control department that is depended to production department in Selex Communications. Then I passed to production department.

3.1 First Week

On my first day in Selex Communications, I have given a little conference about what Selex

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is, what Selex does, how powerful Selex is, whom Selex is responsible for and what Selex' main

duties and aims on electronics field are by human resources. After this introduction about Selex

Communications, it's told that what my responsibilities are, what should be done in emergency

situations, what should be done and what should not be done.

After this conference, I was made looked everyplace of the company and I was made

informed about all different parts of the company. Then I were taken to production department.

In production department, I met with production engineers Levent Akin and Sami Tokgoz.

They told what they do in this company, what they responsible for. Leven Akin gave me some

important instructions about ESD (electrostatic discharge). Then he told me how to prevent ESD

from PCB's. First he showed us white shirts to be protected from ESD, then he introduced wrist

band. All workers in the company were using white shirts and wrist bands on their desk while they

work. He made me look all places of production part, he showed us PCB design levels, and gave

some instructions about PCB assembly machines.

After these knowledge about ESD and what is PCB is, I've been forwarded to quality control

department that is a part of production department in Selex Communications. In here, I was

introduced to quality control personals Ramazan Soy, Bayram Cetinkaya and Hasan Anac. First

two week period, I were located in quality control department and learned about what quality

control is and for.

For the first day, Bayram Cetinkaya showed me how to control production entries. There

were some accessories about measurement and control. I was taught about this accessories, what

these instruments do and how they work.

On my second day, I was charged to control one of A400M lightning panel by using digital

and mechanical calipers. My aim was to measure wanted parts as big as they are in the mechanical

drawing in millimeters. After these measuring operations, I was expected to report these data and

inform who is in charge whether the measurement is valid or rejected by checking the drawing

measurement tolerances. Next, I was introduced A400M cargo plane, and Selex' duty on this project

which is A400M lightning which is about LED technology. I was showed all the places of each light

for example wing light, cargo light, etc.

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On my third day, I checked the components which came from Aselsan whether they are

valid or not. Also I counted components quantity whether they came in true quantity or not. Here I

met a new instrument which counts the number of components. Its working principle was first

assigning a weight to known quantity, and then dividing the whole weight into pieces. So it counts

all little equipment for people. I reported all these data. Same day, I was recognized what capacitors,

inductors, resistors are and what they are used for. Also I've seen toroids, solenoids and integrated

components. Then I was charged to measure inside lights' dimensions and control that they are valid

or not according to the its mechanical drawings by using caliper. After that I determined the invalid

dimensions and reported these data.

On my forth day, I started day with counting and controlling new A400M entries and

reporting result. After this job is done, I met a new instrument which is called megger. I used

megger to control chairs' and desks' grounding measuremtns. Our criteria was all the desk and chair

resistance should be 20 Ohms or lower. I checked all the desks and chairs, then reported the results,

I separated the items which didn't suit the criteria. After this job, I was charged to control of some

A400M PCB's. Again I seperated the inappropriate parts and I reported these to report papers and

gave them to Bayram Cetinkaya. Next, I saw how to examine new coming circuit components' data

sheets to take information about them like their values, tolerances, if exists shelf life, how to be

stored, etc. At the end of the day, I was showed a new accessory which is used for looking

microchips of components. That device seemed me as a television but it was a very different device.

It had magnifying glasses into it so that we could read microchips.

At the last day of this week, I again used megger but this time I used it for ground covers'

resistance measurement. I measured whole company's ground coverings one by one, determined

inappropriate ones and report these data to responsible staff. After these job I again counted new

entries, checked them suitable or not and report the results to our chief Bayram Cetinkaya.

3.2 Second Week

For the second week, my works are similar to the which for the first week.

For the first day in the second week, I measured A400M's lightning control panel's

dimensions using linear height measurement device. This device is very sensitive and has many

usage options like finding linear distance between two points, circle's radius, circle's arch etc. and

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it's used like a computer.

For second day, I checked some circuit elements like resistors, capacitors, inductors,

integrated circuits, etc. whether they are as wanted or not. For this checking, I entered the

company's goods database and I found their data sheets. Then I controlled dimensions of the

elements using caliper compass and values if it was one of resistor, capacitor and inductor, and

number of pins if it was an IC.

For third day, I controlled PCB's whether they had a error or not taking some samples from

them. I controlled them using big lenses and comparing to their mechanical drawing.

For forth and fifth days in second week, I measured C130 cargo plane's lightnings using

caliper compass, micrometer and linear height measurement device. I checked the results and wrote

down into report.

3.2.1 Conclusion of the First Two Weeks

All the two weeks period, the most important thing is meeting with caliper compass (digital

and mechanic) and linear height measurement device, I think. I learned how to measure center to

center, inner side to inner side, outer side to outer side and depth measurements by using a caliper. I

also learned other devices like radius measurer, angle measurer and diameter measurer.

From this time, I know what ESD is, why I should protect our productions from ESD, how a

military company works and what I should obey.

They also informed about us how the company keeps documents of projects. All over my

internship period I saw that all the things are saved and reported to one level up and all the data are

processed into an excel document.

At the end of the first week,I saw that Selex workers were all happy , they made jokes all

the time, but they were always informed what their responsibilities are. Especially Ramazan Soy

was very interested of us, he always made us laugh. Because of him we had a great week and a

great starting in Selex.

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About ESD

Electrostatic discharge (ESD) is the sudden and momentary electric current that flows

between two objects at different electrical potential. The term is usually used in the electronics and

other industries to describe momentary unwanted currents that may cause damage to electronic

equipment.

ESD is a serious issue in solid state electronics. Integrated circuits are made from

semiconductor materials such as silicon and insulating materials such as silicon dioxide. Either of

these materials can suffer permanent damage when subjected to high voltages, as a result there are

now a number of antistatic devices that help prevent static build up.

One of the causes of ESD events is static electrictiy. Static electricity is often generated

through tribocharging the separation of electric charges that occurs when two materials are brought

into contact and then separated. Examples of tribocharging include walking on a rug, rubbing

plastic comb against dry hair, descending from a car, or removing some types of plastic packaging.

In all these cases, the friction between two materials results in tribocharging, thus creating a

difference of electrical potential that can lead to an ESD event.

Another cause of ESD damage is through electrostatic induction.This occurs when an

electrically charged object is placed near a conductive object isolated from ground. The presence of

the charged object creates an electrostatic field that causes electrical charges on the surface of the

other object to redistribute. Even though the net electrostatic charge of the object has not changed, it

now has regions of excess positive and negative charges. An ESD event may occur when the object

comes into contact with a conductive path. For example, charged regions on the surfaces of

styrofoam cups or plastic bags can induce potential on nearby ESD sensitive components via

electrostatic induction and an ESD event may occur if the component is touched with a metallic

tool.

About Caliper

A caliper (British spelling also calliper) is a device used to measure the distance between

two symmetrically opposing sides. A caliper can be as simple as a compass with inward or outward-

facing points. The tips of the caliper are adjusted to fit across the points to be measured, the caliper

is then removed and the distance read by measuring between the tips with a measuring tool, such as

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a ruler. They are used in many fields such as metalworking, mechanical engineering, gunsmithing,

handloading, woodworking and woodturning.

3.3 Third Week

In the third week, I was sent to production department. Slowly I was entering production

details, soldering, pcb design and production operations and A400M project which I had learned

LED technology already. After this period, I usually did same works. Until finishing my internship

period, I usually soldered components to boards, examined and tested A400M and C130 cargo plane

lights and light card or boards.

In the third week, Levent Akin again introduced production unit, production unit’s aims and

production unit’s success about finished projects. Then he introduced me assembly machines

(typesetting machines) which may be the heart or brain of the company. He told me machines a

little bit and mentioned how well performance machines give, where they come from, what their

working principle is etc. Next, I was introduced to technicians, and took my first production job.

This task was about putting pins on connectors. Technicians gave me some equipment like pliers,

crow nose and we put all the pins to connectors one by one. First it was difficult for me because

pins were bent easily and I was charged not to bent any pins. This connectors was a part of one

project of Aselsan,and there were too many connectors and pins around. Actually, the whole time I

spent on pinning connectors,I got nothing as a candidate of engineer. My only gain of pinning

connectors for a week was that I won everybody’s approval. Because while all other internship

students were showing around,I was still pinning the connectors. At the end of the week,my fingers

were expanded.

I did not pin connectors for all the time passed on my third week. Technicians Sema and Eda

were cared about internships a lot. They showed me how to mask a pcb and why they mask pcb s.

Masking a pcb means covering all the components of a board which can be affected from heat with

a special covering tape. I know that not all the components of a board soldered by hand. Because

some components were so small that solder technicians could not see this little equipment even they

used magnifying glasses and even they saw the parts their legs were so small that solder pencil was

too thick to solder .Also,assembly machines are faster than hands and if machines are well-

programmed or used, they give better performances than hands. Because of this factors, pcb boards

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are mainly soldered on assembly machines. Masking is the first step of preparing of boards. So I

learned how to mask a card or where to mask by using covering tapes.

At the end of this week, technicians,especially Sema helped me about soldering. She showed

me how a component should be soldered on pcb. Also, Eng. Levent Akin who is a master of

soldering gave a little conference about soldering. He was quiet good on soldering and he had too

many awards on soldering from USA and Turkey. He goes to USA many times to learn new

soldering technologies and make all the technicians learned these technologies or skills. According

to Levent Akin, the best way of soldering was that first spilling ‘’flux’’ which is a liquid that makes

solder holds stronger around the holes which component will enter,then make the component sit its

place smoothly and correctly, then by using solder pencil, heating up leg of component, then

making ‘’solder bridge’’ by touching the solder between leg and solder pencil and next giving a

support solder around the leg to make solder good enough. My first trials were not good because I

could not give them what they wanted from me. Because good soldering had some criteria like

being bright, not overflowed, not seems like a cone and not to pass the other side in a spreaded or

scattered way. So,they don't allow me for a period to allow their project card,they gave me some

other pcb's to work for. Actually,they did the right thing because Selex is military based company

and Selex work on the top quality to satisfy its customers and when customers visit company,they

want to see all the technicians’ certificates. These certificates are given to technicians by Levent

Akin after two exams,which are teoric and practical exams. So,internship students have no

certificates, then our soldering tasks were illegal or lets say if I make a mistake soldering and if the

inspectors cant notice this mistake, Selex enters a trouble situation. So I did not solder any project

boards on my first days,but future they trusted my soldering and I grabbed many soldering tasks.

3.3.1 Conclusion of Third Week

On my third week, I learned how to pin a connector, why to pin a connector which was if

you don't pin a connector, you can't plug it or another way of saying, aim is making the connector

connects; masking a pcb, how to and why to mask a pcb; and soldering. The most important thing

of this week was learning of soldering. After this time, I know how to solder, and how to solder

quiet good. This was important for me because I have not soldered before neither on my life nor on

my department labs. Also, the other point was ı was enjoying when I was soldering.

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3.4 Forth Week:

On the forth week, I was again worked on production. This week I was introduced and used

new devices. First thing I learned on this week was how to make clean pcb's. Our aim was protect

boards from dust and flux remainders and if we used some chemicals and stickers like latex, epoxy

or lock-tide. I started cleaning the boards from connectors and connector bottoms by using a brush.

Then I used compressor which includes pressured-air to get rid of flux remainders. These were the

parts which I did by hands. After this point,I met a new device, Zero Ion - Ionic Contamination

Tester, which determines a pcb is dirty or not. I made all connectors dirtiness test by using this

device. Zero Ion includes Isotropic Alcohol (%75) and pure water (ionized water), it has 150M ohm

resistance and works on 77 Fahrenheit degrees (=25 Celsius degrees). By helps of ions, device

measures the remainder ratio. Before test, I measure the liquid in zero ion device whether it consists

of %75 alcohol and %25 ionized water. I used a device and did a measurement by taking benefit of

density difference. By helps of ions,device measures the remainder ratio. According to Institute for

Interconnecting Packaging Electronic Printed Circuits, this remainder ratio should be under or

equal to 5mg / inch2, so Selex obeys this ratio. I put on the boards into the device and it gave me a

report about 5 minutes. At the next page there is a print of Zero Ion device for failed and passed two

boards. I made all boards tested on this device. After all the cards were done,we opened the zero ion

device and looked inside of it and tried to understand its working principle. Next, I saw a new

device, soft water technology, which makes water ionized.

On this week, from time to time I again made connectors pinned and masked the boards. I

took serial numbers of CPA POWER circuit components and gave a report to quality control.

Next day, my main interest was on assembly machines. On The line of production the

machines were Fuji Aim,Fuji QP-242E,Fuji IP-II, Conceptronic HVN-HT 102, Dek 265 horizon03i,

own, Wave-solder machine, pcb cleaning machines and an ultrasonic cleaning machine. Some of

this devices were responsible from applying solder,some of them were responsible from mounting

components and some of their duty was cleaning. Fuji aim can assemble 25.000 component in 1

hour. Inside of this machines ,some special fine sieves are used. This fine sieves are peculiar to

every other pcb's. Every board type has its own special fine sieves. This Fine Sieves are made by

computer program and a laser driller. It is so sensitive that a little mistake may cause many

problems. This machine is one of the most developed assemble machines on Turkey. Own’s duty is

heating the Cream solder - Flux mixture step by step. In this phase,boards are not heated

suddenly,because components are affected from thermal shock. Before this step,boards are masked.

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Wave-solder machine makes a wave top and boards are moving ahead and tangent to wave top. So

on that tangent point, board takes solder. This machine works about 250 Celsius degrees. Board

cleaning machines cleans the boards from flux remainders ,dust or alcohol remainders and if used

stickers like latex, locktide. Ultrasonic cleaning machine is a effective device but has high cost

that's why it is not used commonly. It cleans pcb's by sending thousands of waves. Inside of it, there

is a liquid which is highly volative.

In this devices, Selex uses lead - tin (pb-sn) mixture on their solders. In Europe, some

companies started to use copper instead of lead, but still copper could not prove itself. Levent Akin

says still copper is not reliable. In,Fuji aim device,cream solder was used. Before it was used, it was

always mixured with flux. So solder spreads better. At this step, used flux depends on water,

because it can be cleaned via water easily but consequently it is oxidized in a short time if it is not

cleaned. This cream solder has a special construction. This flux – Cream solder mixture is solid at

182 Celsius degrees, whereas it is liquid at 183 Celsius degrees. This 1 Celsius degree difference

makes this solder choice-able. There are some other kind of mixture but they have wider solid -

liquid gap,so they usually are not preferred. While using Cream solder on production line, Staff uses

very special fine sieves peculiar to every other pcb's.

I prepared some thermal mounting pads for ac-dc converters,by using a sticker, I sticked it

on to board and than soldered ac-dc converters on it.

From time to time ,ı visited test unit and used lecroy wave-runner oscilloscope. I learned its

functions and used it for some boards test levels. I could see voltage and current waves on this

devices.

3.4.1 Conclusion of Forth Week:

On this week, I usually got some tasks about production line. I was charged of following and

controlling boards on production line. Again, I reported all the things to my up level personnel

which was technician Emrah Bay. Time to time, I got back to Sema and Eda to help them soldering

and showing new internship students how to pin connectors and helped them on masking boards.

The most important thing of this week was I had learned how to use these pcb assemble machines

and their functions.

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3.5 Fifth Week :

On this week, I still pinned some connectors and carried on masking boards. Also I soldered

components via my hands which was the most enjoyable job for me. Again I took part on

production line, controlling and inspecting of boards.

On this week, I did a new task which was preforming of pwa-gate drive snubber board. I

prepared all the capacitors (4 unit) for assembly and reported these data to technicians and finally

saved these data on excel documents.

I re-soldered the connectors which could not pass on inspection step.(card name was

76463A-01). I soldered two 150 ohms resistances on 49753 boards. After that I soldered one 250

microfarads capacitor on these boards. All of the boards were 178 unit. After that I made jumper

wires on determined pins for all board connectors. After soldering operation, I cleaned boards by

using water and pressured-air. After that I filled 49753 observing forms and reported them to

technicians.

A new connector type arrived to Selex and I helped pinning them. But for this type, I used

locktide to get a better tighten the pins.

I joined another task which was about 622205 named boards which is used on Aselsan’s

Sahingozu project. I used another type of pins and silicon. Then we exiled some locktide on screws

and screwed the boards. I again used locktide for protecting the board from leaking.

I attached 2 connectors on 1001-1039 board which are used for producing images systems. I

remade this task on 52 boards and ı inspected 6527 boards with microscope to verify all soldered

legs are true or not.

3.5.1 Conclusion of Fifth Week:

I did a lot of tasks on this week. I learned many things this week and ı began to get tasks like

workers. Again technicians Sema, Eda and Emrah helped me very much. I got how a company

works at the end of this week.

18

3.6 Sixth Week:

During this week,ı have usually been o cabling. I started this week by controlling cables and

looked the true connectors which is tied on Genesis project boards. I also printed ME-01-221-TRA

circuit boards’ labels and labeled them. I controlled Ins Basetta Display, RF Protection Module and

Modem Module by looking and checking forms. I controlled connector boards, ac/dc converters

board, ıns basetta audio by looking following forms. I controlled bite module and power supplies

again by using following forms. I cleaned PWAPOWER-D-TYPE cards with alcoholic fluid and

masked them (10 units).

I learned how to clean cables by using alcohol and soldered two tips of connector terminals.

I used a new device in order to cable cutting. It can be programmed so that you get cables as having

the length which you want and having the quantity which you need. On that day, I was charged to

cut two types of cables which one of them 3.75 cm and the other was 6.35 cm. Here, I again met

with a new device. Its duty was that opening cable ends how long you need, by turning blades. I

opened ends of all the cables 5mm. After this, I soldered this cables to connectors terminals.

I cut macarons into two piece as each have lengths 6.35mm long and made these macarons

located on J4 connectors’ solder points (300 unit).

I did some S1 key assemblies. I connected key to plaque by using screws,smooth washer and

a adjustable torque. I tied the cables on plaque connecting with the position key.

I carried on cable assemble, controlling documents and materials.

I controlled reference cables which were outgoing cables and adjusted their length to 0.49

meter (20 unit).I cut cables as it would suit to endpoints of RJ45 connectors and isolated them.

Then, I controlled 1, 2, 3 and 6 named endpoints.

I assembled a motor set which is used on Aselsan’s Sahingozu Project. I opened 6.4 mm and

soldered endpoints of black, brown, yellow and orange cables (150 units). I allowed maximum 19

mm service portion from encoder body ending and oriented of cables through motor shaft. I put on

cables in which coming out from the motor as they would be curled minimally 3.3mm out of 25

mm. I controlled macarons which located on cables that came from motor and encoder body. After

these, I inspected cables on motor bodies and then i used a handcuff to make all the cables stand

together.

19

I inspected cables, bent them as they would have length between 0.1 - 1.2 mm and cleaned

them (100 units).

I cut macarons by 25 mm,then connected them to encoder terminals and finally made

connected encoder terminals passed from narrowed macarons. I cut other macarons by 82.5 mm and

narrowed them with cables which came out of encoder body and motor, in it;as there would be a

distance between two macarons (100 unit).

I cut cables such that each were in the same size. I opened their endpoints by 3.2 mm and

soldered their endpoints to cards.

I controlled encoder terminals’ connection points. I controlled macarons on the cables in

order to check whether macarons were narrowed or not (100 unit).

I controlled macarons which located on solder connections of J1 connectors. I found some

missing macarons and replaced new macarons and narrowed them. Then I controlled dirtiness and

physical damage if there existed.

In this week, I also mounted Gokova Frigate's racks.

3.5.1 Conclusion of Sixth Week:

I spent all of my time on cabling, mounting and mechanical assembly. I cut cables, opened

their endpoints and soldered them to their boards or connectors. On this week, I met with Genesis

and Sahingozu projects. My works were usually about Genesis project. But i got tasks on Sahingozu

project’s motor part, too. I controlled, cut cable and opened them for motor body, soldered them and

used macarons to made them stand together.

4. PROJECTS

About Genesis Project

Genesis means Ship Integrates War Administration System. Selex has a duty on Turk

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Warships’ communication and Selex makes inside design of this ship. We, internship students were

not allowed getting information about this project, because this project has to be secret, Selex

Engineers say. There are pictures of Genesis Ship and radar and communication device which Selex

does, below. But, on this project Selex is subcontractor of Havelsan. Selex has a duty only

communications of this ship. Selex sends technicians frequently to Golcuk for this project.

In Selex Communications, I have included in a part of the Genesis Project which I described below

and done some work in the project during this week.

Genesis (Ship Integrates War Administration System) Project’s purpose is the modernization of old

technology production War Management System which is used in G-Class (U.S.A. originated old

Perry Class) Frigates exist in the inventory of Naval Forces Commandership and that of software

and multiple purpose operator consoles by using mostly Commercial Products (Commercial of the

Shelf / COTS).

The Project has signed in November 2004 by Turkish Naval Forces and the companies HAVELSAN

which is the main contractor of the project and AYESAS, YALTES, MILSOFT and SELEX

Communications. as inferior contractors. The project includes the development of Command

Control Software by national opportunities and maintenance of life period of the system with low

cost methods.

By modernization program, production of GENESIS G-Class Frigate War Management System (G-

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GSYS) hardware, adaptation and modification of the software according to changing necessities,

integration and testing of the system, lecturing of required education and maintenance and service

support of the system during its life period are going to be accomplished.

Selex Communications, as an inferior contractor of the project, has taken the renewal of interior and

exterior communication systems of 8 G-Class Frigates of Turkish Naval Forces and the renewal of 2

frigates has already been finished.

About A400M Cargo Plane:

Airbus Military offers the military air transport world a modern, multi-role military air-lifter

which will replace the aging fleets of C-130 Hercules and C-160 Trans-all in service with the air

forces around the world. With the A400M, Airbus Military is setting new airlift standards and

changing the way in which future military programmes will be manage.

The A400M, as the new air-lifter of the 21st century, will have more than twice the payload

and volume of the aircraft it will replace. It will play an essential role in enhancing Europe's airlift

capabilities, whilst enabling the establishment of common support, training and operational

procedures and greater interchangeability in multinational humanitarian and peace-keeping

missions. The A400M Common Standard Aircraft (CSA) is capable of performing:

◦ strategic operations (long range, large capacity, high cruise speed)

◦ tactical missions (soft-field performance, autonomous ground operation, low speed /

low level operations, aerial delivery)

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◦ "in-theatre" tanking operations (receiving as well as dispensing fuel)

Tecnical SpecificationsDimensions Overall Length 45.1 m Wing Span 42.4 m Overall Height 14.7 m

Cargo Box Dimensions Length (excluding ramp) 17.71 m Ramp Length 5.40 m Width 4.00 m Height 3.85 m Height (aft of wing) 4.00 m

Weights (2.25g) Max. Take-off Weight 141 t Max. Landing Weight 122 t Max. Payload 37 t Total Internal Fuel 50.5 t

Performance Cruise Speed Range Mach 0.68 - 0.72 Max. Operating Speed 300 kt CAS Initial Cruise Altitude at MTOW

29 000 ft

Max. Operating Altitude - Normal ops

37 000 ft

Max. Operating Altitude - Special ops

40 000 ft

Range at Max. Payload * 1780 nm Range at 30-tonne Payload * 2450 nm Range at 20-tonne Payload * 3450 nm Ferry Range * 4700 nm Tactical Take-Off Distance ** 914 m Tactical Landing Distance ** 822 m

The A400M is designed to civil certification standards complemented where appropriate by

specific military requirements. The aircraft design incorporates leading state-of-the-art technology

including:

◦ Fly-by-wire Flight Control System with sidestick controllers

◦ Flight envelope protection system, already proven in Airbus commercial aircraft

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◦ Advanced structural design incorporating extensive use of composite materials

◦ High performance turboprop engines, allowing operation in civil air traffic control

environment.

◦ High flotation landing gear, allowing operation from short, unpaved airfields.

Performance:

A400M has been designed to provide high strategic mission efficiency whilst meeting the

demands of tactical operations.

Speed / Altitude Capasity :

The A400M is an economical turboprop aircraft with a cruise speed almost as fast as

turbofan powered transports. Its advanced aerodynamic design, coupled with four new generation,

high performance turboprop engines and 8-bladed propellers provide cruising speeds up to Mach

0.72 at 37 000 ft.

Field Performance:

For tactical missions, good field

performance is a crucial factor for mission

success. The A400M provides excellent soft field

capabilities and requires only a short runway

length, both for take-off and landing. In a combat

situation where it would land on a semi-prepared

forward operating strip and unload all its cargo,

the A400M would require less than 1000 m of

usable runway. The aircraft is capable of

operating into unprepared landing strips under adverse meteorological conditions completely

independent of ground support. With its 12-wheel main gear and high flotation characteristics, the

A400M will be able to land on soft grass fields over low plasticity clay, a performance which far

24

exceeds that of any similar aircraft. Operations from remote sites, with limited or no ground

facilities and limited space for man-oeuvre are severe constraints for a tactical airlifter. The A400M

is designed from the outset to work in these conditions.

◦ A turning radius of 30 m enables the A400M to be operated from simple air bases with

limited aprons and taxiways;

◦ The A400M is capable of reversing up, under its own power, a 2% slope on hard

surfaces and a 1% slope on soft surfaces at its tactical MTW in hot and high conditions.

Aerial Delivery:

As a tactical airlifter, the A400M is capable of air dropping paratroops and equipment via

parachute or gravity extraction. A single load up to 16 tonnes, or multiple loads up to 25 tonnes of

total weight; 116 paratroops plus a wedge load of 6 tonnes. The A400M can drop simultaneously

paratroops and cargo. It can performs as well Very Low Level Extraction (VLLE – 15 ft above

ground) of a single load up to 6.35 tonnes, or 3 individual loads, each up to 6.35 tonnes. Aerial

delivery by gravity extraction of a single load up to 4 tonnes, or multiple loads up to 20 tonnes of

total weight can be performed by a nose-up attitude or by being manually dispatched.

Air-To-Air Refuelling:

The A400M is also quickly convertible into a tactical tanker. The flight envelope of the

A400M allows it to refuel a wide range of aircraft and helicopters, at the altitudes appropriate to

their missions.

◦ A two-point trailing drogue system can be installed within two hours by fitting two

standard air-to-air refuelling pods (optional) to the multi-role attachment points on the

wings. Each pod provides a fuel flow of up to 1200 kg/min.

◦ A centre-line pallet-mounted hose drum unit can be fitted in the rear cargo bay. It

provides a fuel flow of 1800 kg/min.

25

To enhance the fuel volume, up to two optional cargo hold fuel tanks (CHT) can also be

installed, providing up to 5.7 tonnes at extra fuel each. These additional tanks connect directly to

the aircraft's fuel system and thus become part of the A400M's computer-controlled centralised fuel

management system.

Designed from the outset to be a dual-role air transport and air-to-air refuelling aircraft, the

versatile A400M offers air commanders and planners new levels of flexibility in the delivery of air

power. Its basic fuel capacity of 50.5 tonnes or up to 60 tonnes with two optional Cargo Hold Tanks

fitted, coupled with its own low fuel-burn rate, makes it an efficient aerial tanker and a cost-

effective way for air forces to acquire an aerial refuelling capability.

Cargo Handling:

The entire range of current and anticipated loads defined in the European Staff Requirement are all

within A400M's carrying capability. Military loads ranging from armored combat vehicles and

artillery to attack and utility helicopters and civil loads such as excavators and dump trucks can all

be accommodated. The A400M cargo box dimensions are optimized for the transportation of heavy

vehicles and / or cargo pallets, as well as being easily configured to carry troops, paratroops, or

Medevac.

26

The A400M cargo handling system allows for pallets and containers to be loaded / unloaded

by a single loadmaster, without any special ground support equipment. An optional 5-tonne crane

can be installed at the rear of the fuselage allowing loading and unloading of fully loaded military

pallets.

The cargo hold provides enough space to carry nine standard military pallets (88in x 108in)

including two loaded on the ramp area. Civil pallets (125in-wide) can also be loaded using an

optional roller/restraint system. Simultaneously 54 troops can be seated in the side-wall seats. The

pallet roller/ restraint system can easily be stowed to provide a flat floor for tracked or wheeled

vehicle loading.

The A400M cargo bay can accommodate up to 116 fully equipped troops / paratroops,

seated in four longitudinal rows. Paratroops can be dropped from the rear doors or from the ramp.

The hold can also be converted for a medical evacuation role (MEDEVAC) allowing

up to 66 stretchers accompanied by 25 medical personnel.

Power Plant:

In order to fulfil the requirement of both strategic and tactical mission performance, the

A400M is powered by new-generation TP400-D6 turboprop engines. Four turboprops each rated at

over 11 000 shp contribute to excellent performance characteristics which enable A400M to

transport a variety of loads and personnel over long distances at high cruise speed. The TP400-D6 is

being developed, manufactured and supported by EuroProp International (EPI), a European joint

venture company consisting of Rolls-Royce, Snecma Moteurs, MTU Aero Engines and Industria

deTurbopropulsores (ITP).

The powerplant uses Ratier-Figeac FH386 propellers that allows the aircraft to fly up to a

cruise speed of Mach 0.72.

The propeller blades are of composite construction, having a carbon spar and a composite

shell. A polyurethane coating is applied on the shell to protect against erosion. Electrical de-icing is

used along the leading edge. The outer part of the blade leading edge has a nickel guard to protect

27

against erosion.

Propeller control is integrated into the FADEC, thus reducing pilot workload. The FADEC

controls the blade pitch angle in order to maintain the propeller at a constant, optimum-efficiency

speed. It also provides an autofeathering capability upon automatic detection of an engine failure.

Turboprops provide the optimum combination of take-off and landing performance, cruise

fuel efficiency and tactical mission performance such as manoeuvring on the ground, steep descents

and air-dropping. A turboprop engine consumes 20% less fuel per mission relative to a turbofan,

leading to lower operating weights, and hence lower acquisition and operating costs and optimised

payload.

Cost Effectiveness:

The selective application of advanced technologies only in areas where these can

demonstrate clear added value has long been an Airbus hallmark, giving Airbus products a distinct

competitive edge.

The A400M has been sized to have the best balance of cargo load weight and volume. This

enables the aircraft to achieve an average per sortie payload of around 70% of total aircraft payload.

Only the A400M matches its maximum payload, and therefore aircraft weight, to the required

'outsize' volume of today's modern loads. This is important, as an aircraft's weight largely

determines its acquisition and operating & support costs.

Life Cycle Costs:

The acquisition price is only a portion of the total costs of owning and operating an aircraft.

The Life Cycle Costs (LCC) are also affected by downstream fuel and other operating & support

costs. These will vary for each type of aircraft owing to many factors such as types of engine,

aircraft size, and technology employed. A fair comparison can be obtained by calculating the LCC

corresponding to the aircraft fleet required to perform a typical mission.

28

A fleet of 50 A400M airlifters represents an acquisition cost of 5bn-Euros and a 30-year total

LCC of 10bn-Euros. When compared to a corresponding fleet of competing aircraft required to

obtain the same overall airlift capability, the A400M will have the lowest 30-year life cycle cost.

Typical Missions:

There is no such thing as a 'standard mission'. However, many of the A400M's capabilities,

both logistic and tactical, can be demonstrated through the use of generic deployment scenarios. On

the next pages,there are detailed pictures of A400M

About LED Technology:

LEDs may be little, but new high-brightness models are producing a considerable amount of

light.

First used as status and indicator lamps, and more recently in under-shelf illumination,

29

accent lighting, and directional marking applications, high-brightness LEDs have emerged within

the last six years. But only recently have they been seriously looked upon as a feasible option in

general purpose lighting applications. Before you recommend or install this type of lighting system,

you should understand the basic technology upon which these devices are based.

Light-emitting diodes (LEDs) are solid-state devices that convert electric energy directly

into light of a single color. Because they employ “cold” light generation technology, in which most

of the energy is delivered in the visible spectrum, LEDs don't waste energy in the form of non-light

producing heat. In comparison, most of the energy in an incandescent lamp is in the infrared (or

non-visible) portion of the spectrum. As a result, both fluorescent and HID lamps produce a great

deal of heat. In addition to producing cold light, LEDs:

◦ Can be powered from a portable battery

pack or even a solar array.

◦ Can be integrated into a control system.

◦ Are small in size and resistant to

vibration and shock.

◦ Have a very fast “on-time” (60 nsec vs

10 msec for an incandescent lamp).

◦ Have good color resolution and present

low, or no, shock hazard.

The centerpiece of a typical LED is a diode

that is chip-mounted in a reflector cup and held in

place by a mild steel lead frame connected to a pair of electrical wires. The entire arrangement is

then encapsulated in epoxy. The diode chip is generally about 0.25 mm square. When current flows

across the junction of two different materials, light is produced from within the solid crystal chip.

The shape, or width, of the emitted light beam is determined by a variety of factors: the shape of the

reflector cup, the size of the LED chip, the shape of the epoxy lens and the distance between the

LED chip and the epoxy lens. The composition of the materials determines the wavelength and

color of light. In addition to visible wavelengths, LEDs are also available in infrared wavelengths,

from 830 nm to 940 nm.

30

The definition of “life” varies from industry to industry. The useful life for a semiconductor

is defined as the calculated time for the light level to decline to 50% of its original value. For the

lighting industry, the average life of a particular lamp type is the point where 50% of the lamps in a

representative group have burned out. The life of an LED depends on its packaging configuration,

drive current, and operating environment. A high ambient temperature greatly shortens an LED's

life.

Additionally, LEDs now cover the entire light spectrum, including red, orange, yellow,

green, blue, and white. Although colored light is useful for more creative installations, white light

remains the holy grail of LED technology. Until a true white is possible, researchers have developed

three ways to deliver it:

◦ Blend the beams. This technique involves mixing the light from multiple single-color

devices. (Typically red, blue, and green.) Adjusting the beams' relative intensity yields the

desired color.

◦ Provide a phosphor coating. When energized photons from a blue LED strike a phosphor

coating, it will emit light as a mixture of wavelengths to produce a white color.

◦ Create a light sandwich. Blue light from one LED device elicits orange light from an

adjacent layer of a different material. The complementary colors mix to produce white. Of

the three methods, the phosphor approach appears to be the most promising technology.

Another shortcoming of early LED designs was light output, so researchers have been

working on several methods for increasing lumens per watt. A new “doping” technique increases

light output several times over compared to earlier generations of LEDs. Other methods under

development include:

◦ Producing larger semiconductors.

◦ Passing larger currents with better heat extraction.

◦ Designing a different shape for the device.

◦ Improving light conversion efficiency.

◦ Packaging several LEDs within a single epoxy dome.

31

One family of LEDs may already be closer to improved light output. Devices with enlarged

chips produce more light while maintaining proper heat and current management. These advances

allow the units to generate 10 times to 20 times more light than standard indicator lights, making

them a practical illumination source for lighting fixtures.

Before LEDs can enter the general illumination market, designers and advocates of the

technology must overcome several problems, including the usual obstacles to mainstream market

adoption: Industry-accepted standards must be developed and costs must be reduced. But more

specific issues remain. Things like lumen-per-watt efficacy and color consistency must be

improved, and reliability and lumen maintenance should be addressed. Nevertheless, LEDs are well

on their way to becoming a viable lighting alternative.

Advantages of Using LEDs:

◦ LEDs produce more light per watt than incandescent bulbs; this is useful in battery

powered or energy-saving devices.

◦ LEDs can emit light of an intended color without the use of color filters that traditional

lighting methods require. This is more efficient and can lower initial costs.

◦ The solid package of the LED can be designed to focus its light. Incandescent and

fluorescent sources often require an external reflector to collect light and direct it in a usable

manner.

◦ LEDs are ideal for use in applications that are subject to frequent on-off cycling, unlike

fluorescent lamps that burn out more quickly when cycled frequently, or HID lamps that

require a long time before restarting.

◦ LEDs can very easily be dimmed either by Pulse-width modulation or lowering the

forward current.

◦ LEDs light up very quickly. A typical red indicator LED will achieve full brightness in

microseconds. LEDs used in communications devices can have even faster response times.

◦ LEDs mostly fail by dimming over time, rather than the abrupt burn-out of incandescent

bulbs.

◦ LEDs can have a relatively long useful life. One report estimates 35,000 to 50,000 hours

of useful life, though time to complete failure may be longer. Fluorescent tubes typically are

32

rated at about 30,000 hours, and incandescent light bulbs at 1,000–2,000 hours.

◦ LEDs, being solid state components, are difficult to damage with external shock, unlike

fluorescent and incandescent bulbs which are fragile.

◦ LEDs can be very small and are easily populated onto printed circuit boards.

◦ LEDs do not contain mercury, unlike fluorescent lamps.

◦ Due to the human eye's visual persistence LEDs can be pulse width or duty cycle

modulated in order to save power or achieve an apparent higher brightness for a given power

input. The eye will tend to perceive the peak current light level rather than the average

current light level when the modulation rate is higher than approximately 1000 hertz and the

duty cycle is greater than 15 to 20% . This is also useful when applied to the multiplexing

used in 7-segment displays.

Disadvantages of Using LEDs:

◦ LEDs are currently more expensive, price per lumen, on an initial capital cost basis, than

more conventional lighting technologies. The additional expense partially stems from the

relatively low lumen output and the drive circuitry and power supplies needed. However,

when considering the total cost of ownership (including energy and maintenance costs),

LEDs far surpass incandescent or halogen sources and begin to threaten compact fluorescent

lamps .

◦ LED performance largely depends on the ambient temperature of the operating

environment. Over-driving the LED in high ambient temperatures may result in overheating

of the LED package, eventually leading to device failure. Adequate heat-sinking is required

to maintain long life. This is especially important when considering automotive, medical,

and military applications where the device must operate over a large range of temperatures,

and is required to have a low failure rate.

◦ LEDs must be supplied with the voltage above the threshold and a current below the

rating. This can involve series resistors or current-regulated power supplies.

◦ Most white LEDs have spectra that differ significantly from a black body radiator like

the sun or an incandescent light. The spike at 460 nm and dip at 500 nm can cause the color

of objects to be perceived differently under LED illumination than sunlight or incandescent

sources, due to metamerism , red surfaces being rendered particularly badly by typical

33

phosphor based LEDs white LEDs. However, the color rendering properties of common

fluorescent lamps are often inferior to what is now available in state-of-art white LEDs.

◦ LEDs do not approximate a “point source” of light, so cannot be used in applications

needing a highly collimated beam. LEDs are not capable of providing divergence below a

few degrees. This is contrasted with lasers, which can produce beams with divergences of

0.2 degrees or less.

◦ There is increasing concern that blue LEDs and white LEDs are now capable of

exceeding safe limits of the so-called blue-light hazard as defined in eye safety

specifications such as ANSI/IESNA RP-27.1-05: Recommended Practice for

Photobiological Safety for Lamp and Lamp Systems.

◦ Because white LEDs emit much more blue light than conventional outdoor light sources

such as high-pressure sodium lamps, the strong wavelength dependence of Rayleigh

scattering means that LEDs can cause more light pollution than other light sources. It is

therefore very important that LEDs are fully shielded when used outdoors. Compared to

low-pressure sodium lamps, which emit at 589.3nm, the 460 nm emission spike of white and

blue LEDs is scattered about 2.7 times more by the Earth's atmosphere. LEDs should not be

used for outdoor lighting near astronomical observatories.

LED Technology Compharison with The Other Technologies :

LED lightining technology is based on Solid State Lighting. The purpose of this document is

to show the advantages of LED Lighting with respect to the other technologies.

Importance of Solid State Lighting :

◦ 21% of electric energy use is in lighting.Half of this energy can be saved by switching

to efficient and cold solid-state lighting sources

◦ Solid-state lighting will use visible UV LEDs that are expected to rech lifetimes

exceeding 100.000 hours.At present, LEDs are the most efficient sources of colored light in

almost entire visible spectral range

◦ White phosphor-conversion LEDs already surpassed incandescent in performance.

34

Challanges of Solid State Lighting :

◦ Improve efficiency of light generation

◦ Improve efficiency of light extraction

◦ Improve quality of light

◦ Improve lifecycle of light

◦ Reduce COST

Benefits of LED Lighting:

Luminous Performance (lumens/W) :

35

Luminous Efficiency (lm/W) Comparison :

Life Time In Thousands Of Hours:

36

A400M Lights With LED Technology:

Selex is responsible for all the lights of A400M.I have taken parts on all of these lights’

production stages and test stages. All these ligts uses LED Technology. Here are some them;

Wing Tip Taxi Light :

Wing Tip Navigation-Anticollision Light :

Wingtip Nav/acoll Light is fully based on LED technology. It includes 3 modules in one

structure. Front and back Navigation modules, Anticolision module and IR Anticollision module.

37

HID Power Supply Unit :

38

Aft Navigation and Anti-collision Light :

Landing Light Normal :

39

AAR Flood Light Horizontal Stabilizer:

Rendezvous Light Upper :

40

Hydraulic - Air Conditioning Service Area Light , Fuel Service Area Light , Wheel well Service

Area Light :

Sidewall Light :

41

Floor Light :

Stair Area Light :

42

External Emergency Light :

Emergency Escape Path Light :

43

About TETRA

During first week and the half of the second week of my summer practice, I was desired to

search and understand TETRA (TErrestrial Trunked RAdio) system, so I dealt with searching

througly of this system. Thus, Terrestrial Trunked Radio (TETRA) is a digital trunked mobile radio

standard developed by the European Telecommunications Standards Institute (ETSI). The purpose

of the TETRA standard was to meet the needs of traditional Professional Mobile Radio (PMR) user

organisations. These organizations can be listed as below:

◦ Public Safety

◦ Transportation

◦ Utilities

◦ Government

◦ Military

◦ PAMR

◦ Commercial & Industry

◦ Oil & Gas

Because the TETRA standard has been specifically developed to meet the needs of a wide

variety of traditional PMR user organizations it has a scaleable architecture allowing economic

network deployments ranging from single site local area coverage to multiple site wide area

national coverage. Besides meeting the needs of traditional PMR user organizations, the TETRA

standard has also been developed to meet the needs of Public Access Mobile Radio (PAMR)

operators. TETRA is designed to operate between 150MHz-900MHz, however there are 4 bands

that are agreed on by TETRA developers:

◦ 380-400 MHz

◦ 410-430 MHz

◦ 450-470 MHz

◦ 806-870 MHz

TETRA is a Time Division Multiple Access (TDMA) (see Appendix I) system with 4 user channels

interleaved into one carrier with 25-kHz carrier spacing . Thus;

◦ Users (at most 4), can share 4 timeslots at a same frequency

44

◦ 1 TDMA frame = 4 timeslots (56,67 ms)

◦ 1 multiframe = 18 TDMA frames (1.02 s)

◦ 1 hyperframe = 60 multiframes (61.2 s)

An overview of the network elements covered in the TETRA standard are shown in figure

below ;

Switching and Management Infrastructure (SwMI)

The abbreviation SwMI is used to classify all of the equipment and sub-systems that comprise a TETRA network, including base stations. Even though some ETSI Technical Committee (TC) TETRA members felt that a standard base station interface would be useful (as provided in GSM) it was decided that owing to the way in which different manufacturers configure their networks for optimum performance and design flexibility, it would be impractical to implement.

It was also agreed, for the same reasons as the base station interface, that everything

contained inside the SwMI would not be standardised, thereby allowing TETRA infrastructure

manufacturers flexibility in design, and the ability to differentiate their portfolio offerings, when in

competition with other TETRA manufacturers. This practical approach also meant that new

technologies in the areas of transmission and networking could be used without having to go

through a long standardization process.

45

Air Interfaces

The most important (and complex) interfaces are considered to be the ‘air interfaces’

between the base station and radio terminals (1) and the Direct Mode Operation (DMO) interface

(2). DMO is a facility that allows terminals to operate in local radio nets independent of the main

TETRA network infrastructure.

Peripheral Equipment Interface

This interface standardizes the connection of the radio terminal to an external device, and

supports data transmission between applications resident in the device and the connected TETRA

radio terminal. The PEI also supports certain elements of control within the radio terminal from the

external device and/or application.

Remote Dispatcher Interface

This interface was originally intended to allow connection to remote wire line dispatcher

consoles like those located in major control rooms. Unfortunately, work on this interface was

dropped in ETSI TC TETRA as the complexity to provide a universal interface without degrading

performance was impractical. This was because the PMR industry had specialist manufacturers of

control room equipment, the majority of which differed in the way they interfaced to PMR

networks. Similarly, the TETRA network architecture of manufacturers also differed adding to the

complexity of providing a universal interface. For these reasons only TETRA manufacturer specific

interface specifications are available to support the many voice and data applications requiring

access to TETRA infrastructures.

PSTN/ISDN/PABX

This standardized interface enables TETRA to interface with the PSTN, the ISDN and/or a

PABX.

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Inter-System Interface

This standardized Inter-System Interface (ISI) allows infrastructures supplied by different

TETRA manufacturers to inter-operate with each other allowing interoperability between two or

more networks. There are two methods of interconnection in the standard, one covering information

transfer using circuit mode and the other using packet mode.

Network Management Interface

Like the local dispatcher interface, it was recognized during standardization activities that a

common network management interface was impractical. Fortunately, this early standardization was

not wasted as it was later turned into a comprehensive guide to assist users in defining network

management requirements.

Security in TETRA

The air interface is very vulnerable to eavesdropping and so modern mobile wireless

communication systems need to have some form of air interface security. This air interface security

is intended to secure the connection between MSs and the network. Air interface security is an

effective means to provide security in a mobile network and some essential security functions can

only be realised by air interface security. In most cases it is sufficient to rely on air interface security

and take no further security measures. However, in TETRA systems needing a very high level of

security, additional security may be required to protect information transmitted from one MS to

another not only over the air interface but also within the network. In this case end-to-end security

provides an efficient solution.

Air interface encryption

User traffic and signalling information can be encrypted over the air interface between the

MS and the SwMI, both for individual and group communications. The Air interface encryption

mechanism is available for Voice and Data in Trunked Mode Operation and in Direct Mode

Operation. The use of several encryption algorithms, both standard and proprietary, is supported.

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Traffic encryption protects user speech and data. Signalling encryption provides

protection from traffic analysis, and prevents an eavesdropper from discovering who is operating in

a particular area, or who is calling who.

End-to-end encryption

The TETRA end-to-end service can be realised in any number of ways. This means that a

user may easily tailor an end-to-end encryption system to their particular requirements. This

flexibility is essential for a standard like TETRA that will be implemented in many forms for

different user groups.

Public Safety organisations will have specific (high) national security requirementsfor their

implementation of end-to-end encryption, which will be different from the requirements of Military

user groups, which have even greater security requirements. All such organisations need to be able

to specify an end-to-end encryption system according to their own requirements. It can also be

expected that commercial user groups will have a need for secure end-to-end encryption systems.

Advantages of TETRA in Market

TETRA is an open standard developed by the European Telecommunications Standards

Institute (ETSI). The main purpose of the TETRA standard was to define a series of open interfaces,

as well as services and facilities, in sufficient detail to enable independent manufacturers to develop

infrastructure and terminal products that would fully inter-operate with each other as well as meet

the needs of traditional PMR user organizations.

The initial responsibility of ETSI Project TETRA (now known as ETSI Technical

Committee (TC) TETRA) was to deliver as set of standards, under a mandate from the European

Commission, for a Digital Trunked PMR communications system that could be deployed in Western

Europe. As well as producing these mandatory ETSI deliverable (now completed), TC TETRA’s

responsibility was, and still is, to make sure that the portfolio of standards continue to be developed

in accordance with user needs and priorities.

The technology solutions chosen to meet user requirements contained in the TETRA

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standards have been, and continue to be, developed primarily by well know and respected

manufacturers who have been serving the PMR market with products and services for several

decades. This combined “Know How” ensures that optimum technology solutions are chosen to

meet user requirements. Details of manufacturers can be viewed on the member’s page of the

TETRA Association by clicking on the left hand menu under core products.

Although the prime responsibility of ETSI is to develop standards for Europe, many of its

standards are also adopted world-wide, as evidenced by the uptake of GSM, the first wireless

technology standard to be developed by ETSI. Similarly, TETRA has already been deployed in

many regions and nations outside Europe, resulting in TETRA becoming a truly global standard.

There is no doubt that a proprietary technology solution can be brought to market in less time than a

solution conforming to a recognized open standard. However, large user organizations, especially

those in the public sector, have recognized that some proprietary solutions can meet their needs but

the ‘tie in’ to a single supplier can have significant disadvantages. Even though there are some

disadvantages, the main advantages and benefits of adopting an open standard are:

◦ Economies of scale provided by a large harmonized market served by several

independent manufacturers and suppliers competing for the same business resulting in

competitively priced solutions

◦ Second source security if existing suppliers exit the market

◦ Evolution (instead of revolution) of the technology standard ensuring longevity and

good return on investment for both users and suppliers

◦ Choice of manufacturers for new products keeping prices down

◦ Greater choice of products for specialized applications

◦ Greater responsiveness to future needs by existing suppliers because of competition

Because there are several independent manufacturers of both TETRA network infrastructure and

radio terminals all the benefits of standardization listed also apply to the TETRA market.

Sound-Powered Telephone

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A sound-powered (SP) telephone is a

communication device that allows users to talk each other

with the use of a handset, similar to a conventional

telephone, but without the use of external power Sound-

powered telephones are widely used on naval vessels.

The speaker’s voice supplies necessary power for

operation, so no batteries and power connections are

required. So that, communication is never interrupted by

a power failure.

The headset microphone transducer converts sound pressure from a user’s voice into an

electrical current. This current, too small to be measured by ordinary instruments, travels to the

receiver where is then converted back to sound by a transducer.

A sound-powered telephone circuit can be as simple

as two handset connected with a pair of wires.It can have

two or more stations on the same circuit. The circuit is always

live, thus user simply begins speaking rather than dialing

another station.

Speech is transmitted clearly and distinctly,

because all static noise associated with battery type

telephones is eliminated. In normal conditions, 30 miles or

more transmission is assured.

This equipment is designed to answer the demands for reliable shipboard communication. It

is also used in Turkish Naval Forces’ Vessels. Other uses are the emergency communications

systems for high-rise buildings, draw bridges and ideal for use in airports, fire and resque crews,

public utilities, schools, vaults, refrigeration plants, mining operations, ski lifts and civil defense; in

heavy manufacturing plants, shipping docs, sport arenas and road building projects which are high-

noise locations.

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About Dual-Tone Multi-Frequency (DTMF) Decoder Project

Genesis Alarm/Announcement Interface Unit

The capacity of the unit is 6 announce and 6 alarm channels. Alarm/Announcement interface

unit (AAIU) shall interface Master and Slave DSU-Digital Switching Units to the

alarm/announcement control lines of the Alarm/Announce equipment. Capacity of the unit is 6

announce and 6 alarm channels

Alarm module:

◦ Capacity of the alarm module is 6 channels.

◦ Alarm channel selection is based on the DTMF signals while PTT-Push To Talk button is

activated.

Announce module:

◦ Capacity of the alarm module is 6 channels.

◦ Alarm channel selection is based on the DTMF signals while PTT-Push To Talk button is

activated.

◦ After the channel selection, audio signals from the operator terminals redirected to the

selected channels.

The Unit is supplied by a 28 VDC power source and connected to the Alarm Announce

System of the vessel. Inside the unit there exist two sensors which are Heat & Humidity Sensors.

Dual-Tone Multi-Frequency (DTMF)

Dual-tone multi-frequency (DTMF) signaling is used for telephone signaling over the line in

the voice-frequency band. The DTMF that is used for telephone tone dialing is known by the

trademarked term Touch-Tone, and is standardized by ITU-T Recommendation.

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The needs of some number of companies have led to the addition of the number sign (#) and

star (*) keys and a group of keys for menu selection: A, B, C, D to the telephone keypad.

Although in present-days uses of A, B, C, D keys on

telephone networks are few, the DTMF keypad is laid out in a

4x4 matrix, with each row representing a low frequency and

each column representing a high frequency

For example pressing a single key such as

‘1’ will send a sinusoidal tone of the two

frequencies 697 and 1209 Hertz (Hz) (Fig.

3.2.1.2.-1). The frequencies may not vary more

than ±1.5% from their nominal frequency, or the

switching center will ignore the signal. The

loudness difference between the high and low frequencies can be as large as 3 decibels (dB) and is

referred to as “twist”.

These multiple tones are the reason for calling the system multifrequency. No frequency is a

multiple of another, the difference between any two frequencies does not equal any of the

frequencies and sum of the frequencies does not equal any of the frequencies. The frequencies are

designed with a ratio of 21/19, which is slightly less than a whole tone. These tones are then

decoded by the switching center to determine which key was pressed. In the project we designed a

decoder circuit and first build it on the breadboard with LEDs as indicators. The circuit schematics

and the explanations can be found on the following pages.

DTMF Decoder Circuit

We have used MT8870 IC chip (Fig. 3.2.1.3.-1) as DTMF

decoder which is a complete DTMF receiver integrating both

the bandslip filter and digital decoder functions. It uses digital

counting techniques to detect and decode all 16 DTMF

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tonepairs into a 4-bit code.

We set up the similar circuit in the datasheet as named “Single Ended Input Configuration”,

However we used also IN+ input (“Double Input Configuration”) since audio inputs have two lines.

About Audio Analyzer Project

After dealing with the DTMF decoder circuit, I have started the real challenging part of my

internship at Selex Communications. I have learnt so many things on engineering; such as how to

approach a problem, reading datasheets, PIC Programming with C Language and getting/sending

data to an audio device from a PC via PIC16F877 and most importantly: patience and team work..

Genesis SP Telephone Audio Module Interface

SP (Sound Powered) Telephone Audio Module (3 Channel) (SPTAM) shall interface master

and slave CD (Digital Switching Units(DSU)) units to 3 channels between the subscribers of the SP

telephone network and the operator terminal (Multi Functional User Terminal (MFUT)) connected

to the DSUs. Capacity of the module is 3 channels. See the following block diagram of SPTAM.

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It shall allow bidirectional half-duplex* communication in between the subscribers of the SP

telephone network and the operator terminals (MFUT) connected to the DSUs.

It shall amplify the audio coming from the SP telephone to drive both DSU Rx channels. It

shall amplify the audio from the DSU channel with active PTT to drive the SP telephone network.

Each module shall control 3 SP channels.

5. CONCLUSION:

Besides the work I have done during the summer project, I think that the most useful part of

my summer project was the opportunity to see how real engineers work, what are their principles in

approaching complicated problems, how they collect the efficient and useful information and how

important the team work is and how important to be aware of one’s responsibilities to his colleagues

and partners. To do my summer project in SELEX Communications was really big chance for me,

because since the work done there, is for military purposes, the engineers there always seek for the

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newest and the strongest products of the market. Although being not included with their projects,

due to secrecy and complexity, I had the opportunity to observe and realize how team work is

important and how to behave professional during the duration of a project. The engineers working

on the same project are always in touch in sense of their work and they take care of each other when

there is any problem in any part of a project, knowing that one’s success is indeed the success of all.

SELEX Communications is one of the places where new technologies born and shape in the hands

of engineers. In this sense, I was impressed much when I saw the importance, the creativity and the

diligence of an engineer in real world. Having met with both practical and theoretical aspects of

being an engineer, as a candidate of engineer I become more decided than I was ever before in

being an engineer. Besides, I have been introduced to some working fields of an engineer during the

orientation week to SELEX Communications, and I was able to think about in what area I can

proceed in and specialize. Since I have done my summer practice in production & test division, I

had the opportunity to know a little bit better about telecommunication, embedded systems and

digital design, I become more interested in signal processing and embedded systems. So, I think to

have my elective courses on these fields.

Moving back to my tasks during my summer practice, I had the opportunity to help my

engineers and technicians , since he would operate the implementation of a new system for a

governmental organization. So, I had the opportunity of learning LED Technology by the helps of

A400M cargo plane.A400M has similar points with C130 cargo planes but A400M is stronger of all

cargo planes that have ever been done .This project was very important so I should have taken my

care on top.

The other works I was given did not require creativity of me however it was helpful by

means of practical work. From the courses I took in university, I was familiar with soldering,

putting the right elements in right place, testing any device and determining if the test results are

appropriate or not. However, I saw that I was able to do soldering much more effective and stronger.

(using flux, tinning with soldering pot etc...) The technicians working there showed me how to

solder, that it was a small soldering lesson. Then during the preparation of the test equipment I

explained above, I was able to work very fast and effective by means of the soldering lessons. On

the other hand, due to time restrictions, I was forced to work with full concentration and speed to

satisfy the dead line. During the tests of the lights, I had the opportunity to take responsibility, to

work with other engineers in full confidence and to practice how to cope with negative incidents.

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Finally, this first summer project was a real opportunity and chance to be decided in being

an engineer and loving this profession. Also Selex Communications is of the important companies

in Turkey and it is growing very fast. I completed my practice with a good experience in this

company.

6. REFERANCES

Datasheets which engineers gave me on word documents and pdf documents.http://www.airbusmilitary.com/standards.html

http://www.selex-comms.com.tr/tr/

http://www.selex-comms.co.uk/selex/index2.htm

http://www.tetra-association.com/tetramou.aspx?id=44

http://www.ssm.gov.tr/TR/savunmasanayiimiz/ssurunleri/urunelektronik/Pages/GemiEntegreSavasi

dareSistemiGenesis.aspx

http://en.wikipedia.org/wiki/LED

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