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Transcript of staj raporu
Hacettepe UniversityDepartment of Electrical and Electronics Engineering
Summer Practice Report
Student'sSurname, Name : Artan, ErdemID : 20522044E-Mail : [email protected] 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 : [email protected]
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
2
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.
5
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.
8
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.
10
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
13
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.
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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.
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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.
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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.
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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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