Sunday, September 14, 2008

Special attention....for Sri LAnkans

Just Dial

#132#


from your mobile phone....

(Dialog, Tiogo, Mobitel,Hutch)

If you are not the owner

Register Your SIM Now...


Saturday, July 12, 2008

Try to reduce long time calls

A very important message to everyone,I reserved this as Email.
please read it carefully.


1 Egg, & 2 Mobiles
65 minutes of connection between mobiles.

We assembled something as per image:








Initiated the call between the two mobiles and allowed 65 minutes approximately...
During the first 15 minutes nothing happened;
25 minutes later the egg started getting hot;
45 minutes later the egg is hot;
65 minutes later the egg is cooked.





Conclusion: The immediate radiation of the mobiles has the potential to modify the proteins of the egg. Imagine what it can do with the proteins of your brains when you do long calls.

Please try to reduce long time calls on mobile phones and pass this to all your friends & Family you care for.

Monday, July 7, 2008

Diploma Classes started

My Friends, City & Guild Diploma (2008/2009) classes just started.
Contact your education Institute soon for more details...

Tuesday, June 10, 2008

Go Higher as a Charted Engineer

The places where you can study City & guilds "Telecommunication Systems" in Sri Lanka.

Sri Lankan Main Branch

City & Guilds
Level 6,
Access towers,
278,Union place
Colombo - 2

Tel - 5361427/8
Email - info@cityandguilds.lk

www.cityandguilds.com

-------------------------

Institutes

Sri Lanka Telecom (SLT),

Welisara,Moratuwa - 2956721, 0777 315467 ,071 6139999,
2645500, 2645502, 2645644
Peradeniya, - 081 2388500, 081 2389111
Galle - 091 2232245, 091 2222300

-------------------------
Alexandra college of professional Studies,
Colombo 10

4995636 / 2856402

-------------------------
APSS International Networks (Pvt) Ltd.
Colombo 6

2361587 / 2506803

-------------------------
Aquinas College of Higher Studies,
Aquinas Engineering Faculty
Colombo 8

2694014-5 / 4618689

-------------------------
IDM Vocational Training Division
Colombo 4

2507580

------------------------

Sri Sumangala Vidyalaya,
Colombo 10

2745111 / 077 7736634

------------------------

Technical Education Institute
Colombo 10

2677111 / 2686444

Tuesday, June 3, 2008

Dont use mobile phones when recharging

A few days ago, a person was recharging his cell phone at home.

Just at that time a call Came in and he answered it with the
Instrument still connected to the outlet.



After a few seconds electricity flowed into the cell phone unrestrained
and the young man was thrown to the ground with a heavy thud.

His parents rushed to the room only to find him unconscious,
with a weak heartbeat and burnt fingers.



He was rushed to the nearby hospital, but was pronounced dead on arrival.

Cell phones are a very useful modern invention.



However, we must be aware that it can also be an instrument of death.



Never use the cell phone while it is hooked to the electrical outlet!

My dear Friends I reserved this as E mail.
pls inform your friends about this matter....

Tuesday, May 27, 2008

City & Guild Telecommunication System Engineering Certificate Level - Book List

e books,buy books,telecommunication books,sell book,free books,
These books will help you to improve your knowledge and for your exams try to find them,
We can buy some books online or locally but I was unable to find all books.
So I m waiting for your comments...Pls help to everyone to find these books....My blog is waiting for you..!



City & Guild Telecommunication System Engineering Certificate Level

Recommended Book List - Syllabus 2002 Edition

Fundamental of Electronic Communication 1



Health and Safety

1. The First Aid Manual (7th edition) - Dorling Kindersley

2. The Health and Safety Handbook - Pat McGuiness and Lynn Smith

-----------------------------------------------------------------------------------------
Mathematics

3. Mathematics the Basic Skills (5th edition) - S.Llewellyn & A.Greer

4. Teach Yourself Mathematics - Trevor Johnson & Hugh Neill

-----------------------------------------------------------------------------------------
Introduction to use of Computer technology

5. Essential Computers;Creating Worksheets - Robet Dinwiddie

6. Sams Teach Yourself Microsoft Access 2000 in 10 Minutes - Faithe Wempen

-----------------------------------------------------------------------------------------
Science and electronics

7. Basic Electrical and Electronic Engineering (4th edition) - E.C.Bell & R.W. Whitehead

8. Success in Electronics (2nd edition) - Tom Duncan

-----------------------------------------------------------------------------------------

Communication Systems and Digital Networks 1

-----------------------------------------------------------------------------------------
Information transmission

9. Technician's Guide to Electronic Communications - Frederick L.Gould

10.Telecommunication Technologies - John Ross

11.Illustrated Telecom Dictionary (3rd edition) - Jade Clayton

-----------------------------------------------------------------------------------------
Simple Telecommunication Systems

#. Technician's Guide to Electronic Communications - Frederick L.Gould

#.Telecommunication Technologies - John Ross

-----------------------------------------------------------------------------------------
Optical fiber systems

12.Introduction to Fiber Optics - John Crisp

13.Telecom Factbook - Joseph A.Pecar and David A.Garbin

-----------------------------------------------------------------------------------------
Principales of radio

14.Basic Radio Principles & Technology - Ian Poole

15.Audio,Video and Data Telecommunication - David Peterson

-----------------------------------------------------------------------------------------
Mobile radio and cellular telephone systems

# .Basic Radio Principles & Technology - Ian Poole

16.Wireless Crash Course - Paul Bedell

-----------------------------------------------------------------------------------------
Television

# .Audio,Video and Data Telecommunication - David Peterson

-----------------------------------------------------------------------------------------
Public Switched Telephone Networks (PSTN)

17.Telephone Installation Handbook (2nd edition) - Steve Roberts

18.Telephone Switching Systems - Richard A.Thompson

-----------------------------------------------------------------------------------------
Digital Networks and Data Communication

19.Telecommunication Protocols - Travis Russell

-----------------------------------------------------------------------------------------

Monday, May 26, 2008

City & Guild Telecommunication Diploma

My Friends,

City & Guild Telecommunication Diploma is going to start (2008/2009).

Contact your City & guild education institute soon.

Saturday, May 3, 2008

What Can WiMAX Do?

WiMAX operates on the same general principles as WiFi -- it sends data from one computer to another via radio signals. A computer (either a desktop or a laptop) equipped with WiMAX would receive data from the WiMAX transmitting station, probably using encrypted data keys to prevent unauthorized users from stealing access.
The fastest WiFi connection can transmit up to 54 megabits per second under optimal conditions. WiMAX should be able to handle up to 70 megabits per second. Even once that 70 megabits is split up between several dozen businesses or a few hundred home users, it will provide at least the equivalent of cable-modem transfer rates to each user.

The biggest difference isn't speed; it's distance. WiMAX outdistances WiFi by miles. WiFi's range is about 100 feet (30 m). WiMAX will blanket a radius of 30 miles (50 km) with wireless access. The increased range is due to the frequencies used and the power of the transmitter. Of course, at that distance, terrain, weather and large buildings will act to reduce the maximum range in some circumstances, but the potential is there to cover huge tracts of land.

Friday, May 2, 2008

How Wi-MAX Works......

In practical terms, Wi-MAX would operate similar to Wi-Fi but at higher speeds, over greater distances and for a greater number of users. Wi-MAX could potentially erase the suburban and rural blackout areas that currently have no broadband Internet access because phone and cable companies have not yet run the necessary wires to those remote locations.

WiMAX transmitting tower


A WiMAX system consists of two parts:

  • A WiMAX tower, similar in concept to a cell-phone tower - A single WiMAX tower can provide coverage to a very large area -- as big as 3,000 square miles (~8,000 square km).

  • A WiMAX receiver - The receiver and antenna could be a small box or PCMCIA card, or they could be built into a laptop the way WiFi access is today.

A WiMAX tower station can connect directly to the Internet using a high-bandwidth, wired connection (for example, a T3 line). It can also connect to another WiMAX tower using a line-of-sight, microwave link. This connection to a second tower (often referred to as a backhaul), along with the ability of a single tower to cover up to 3,000 square miles, is what allows WiMAX to provide coverage to remote rural areas.


wi max,wi fi,

What this points out is that WiMAX actually can provide two forms of wireless service:

  • There is the non-line-of-sight, WiFi sort of service, where a small antenna on your computer connects to the tower. In this mode, WiMAX uses a lower frequency range -- 2 GHz to 11 GHz (similar to WiFi). Lower-wavelength transmissions are not as easily disrupted by physical obstructions -- they are better able to diffract, or bend, around obstacles.

  • There is line-of-sight service, where a fixed dish antenna points straight at the WiMAX tower from a rooftop or pole. The line-of-sight connection is stronger and more stable, so it's able to send a lot of data with fewer errors. Line-of-sight transmissions use higher frequencies, with ranges reaching a possible 66 GHz. At higher frequencies, there is less interference and lots more bandwidth.

WiFi-style access will be limited to a 4-to-6 mile radius (perhaps 25 square miles or 65 square km of coverage, which is similar in range to a cell-phone zone). Through the stronger line-of-sight antennas, the WiMAX transmitting station would send data to WiMAX-enabled computers or routers set up within the transmitter's 30-mile radius (2,800 square miles or 9,300 square km of coverage). This is what allows WiMAX to achieve its maximum range.



Special Thanks goes to Prabath Ariyarathna..


Wednesday, April 23, 2008

Be careful when you SMS......

A True Story:      This lady has changed her habit on the hand phone after her handbag was stolen.     Her handbag which contained her mobile, credit card, purse etc. was stolen.     Twenty minutes later when she called her hubby, telling him what had happened,     her hubby says 'I've just received your SMS asking about our     Pin number and I've replied a little while ago.'      When they rushed down to the bank, the bank staff told them all the money was already withdrawn.     The pickpocket had actually used the      stolen hand phone to sms 'hubby' in the contact list and got hold of the pin number.      Within 20 minutes he had withdrawn all the money from the bank account.        Moral of the lesson:      Do not disclose the relationship between you and the person in your      contact list. Avoid using names like Home, Honey, Hubby, Sweetheart,      Dad,      Mum etc...... and very importantly, when sensitive info is being asked      thru SMS, CONFIRM by calling back.      PLEASE PASS THIS story ON TO YOUR LOVED ONES AND FRIENDS
A True Story:

This lady has changed her habit on the hand phone after her handbag was stolen.
Her handbag which contained her mobile, credit card, purse etc. was stolen.
Twenty minutes later when she called her hubby, telling him what had happened,
her hubby says 'I've just received your SMS asking about our
Pin number and I've replied a little while ago.'

When they rushed down to the bank, the bank staff told them all the money was already withdrawn.
The pickpocket had actually used the

stolen hand phone to sms 'hubby' in the contact list and got hold of the pin number.

Within 20 minutes he had withdrawn all the money from the bank account.



Moral of the lesson:

Do not disclose the relationship between you and the person in your

contact list. Avoid using names like Home, Honey, Hubby, Sweetheart,

Dad,

Mum etc...... and very importantly, when sensitive info is being asked

thru SMS, CONFIRM by calling back.

PLEASE PASS THIS story ON TO YOUR LOVED ONES AND FRIENDS

Monday, April 21, 2008

Potential New risk from mobile phones...

scientists have discovered that exposing human endothelial cells- which line the minute blood vessels in the brain - to mobile phone radiation can damage the blood-brain barrier,a vital safety barrier that stops harmful substances in the blood from entering the braiin.
Please use left ear while using cell (mobile), because if you use the right one it will affect brain directly.

scientists have discovered that exposing human endothelial cells- which line the minute blood vessels in the brain - to mobile phone radiation can damage the blood-brain barrier,a vital safety barrier that stops harmful substances in the blood from entering the brain.

I reserved this as an E mail........I think It will useful to you, now you can find about this matter.

Sunday, April 13, 2008

SMS Short Cuts ( part 2 )

BB– bye –bye
LMK– let me know
TXT– text
4– for
4get – forget
4N- foreign /phone
2- to / too / two
2dA– today
2moro– tomorrow
2nit– tonight
GM– Good Morning
GN– good Night
AFAIK– as far as I know
UOK– you okay
ASAP– as soon as possible
ATM – at the moment

Wednesday, April 9, 2008

SMS Short Cuts

SMS Short Cuts ( part 1 )


U – You

R –are

UR – your / you’re

U@ - you at? (Where are you?)

Pls – please

B – be

B4 –before

sry – sorry

THX – thanks

Spk – speak

C – See / sea

CU – See you

CUI - se you later

CB – call back



Wednesday, March 19, 2008

Technician Certificate in Applied Telecommunications City & Guilds

2730 Telecommunication systems
Technician Certificate in Applied Telecommunications

Exam Contents

You have to complete these 2 modules



1.Fundamentals of Electronic Communication 1 (OL)

1. Health and Safety
2. Mathematics
3. Introduction to the use of Computer technology
4. Science and Electronics

2.Communication System and Digital Networks 1 (OL)

5. Information Transmission
6. Simple Telecommunication Systems
7. Optical Fiber Systems
8. Principle of Radio
9. Mobile Radio & Cellular Telephone Systems
10. Television
11. Public Switched Telephone Network –PSTN
12. Digital Networks & Data Communication

Tuesday, March 18, 2008

Do you like to be a Telecommunication System Engineer?

Do you like to be a Telecommunication System Engineer?

City & Guild Telecommunication System is a Better path for it.

This is the Path

Certificate Level – you have to complete 2 modules

Diploma Level – You have to complete 5 modules

Accepted as an entry qualification for engineering council examination.

Advanced Diploma Level – You have to complete 2 Modules

UK based Engineering Qualification.
Equivalent to HND.
Accepted as an entry qualification for engineering council examination graduate diploma(B.Eng). Entry to 2nd or 3rd year in U.K Universities
.


Graduate Diploma Level = B.Eng (degree)

Post Graduate Diploma Level = Msc


Benefits of City & Guilds Qualifications

Internationally recognized qualifications.
Progression through a clearly defined qualifications Structure.
Mobility of employment.


If you need to know something about this, feel free to contact me via E mail.

Sunday, February 24, 2008

EMERGENCY..................!!!!!!

The Emergency Number worldwide for

**Mobile** is

112..

If you find yourself out of coverage area of your mobile network and there is an emergency,

dial 112

and the mobile will search any existing network to establish the emergency number for you,
and
interestingly this number 112 can be dialed even if the keypad is locked.


Try...............!

Sunday, February 17, 2008

How to disable a STOLEN mobile phone?

To check your Mobile phone's serial number, key in the following digits on your phone:

* # 0 6 #

A 15 digit code will appear on the screen. This number is unique to your handset. Write it down and keep it somewhere safe. when your phone get stolen, you can phone your service provider and give them his code. They will then be able to block your handset so even if the thief changes the SIM card, your phone will be totally useless.You probably won't get your phone back, but at least you know that whoever stole it can't use/sell it either.If everybody does this, there would be no point in people stealing mobile phones .

Feel Free..........................

Thursday, February 14, 2008

Have you locked your keys in the car? Does you car have remote keys?


This may come in handy someday. Good reason to own a cell phone.

If you lock your keys in the car and the spare keys are at home, call someone at home on their cell phone from your cell phone.Hold your cell phone about a foot from your car door and have the person at your home press the unlock button, holding it near the mobile phone on their end. Your car will unlock. Saves someone from having to drive your keys to you. Distance is no object. You could be hundreds of miles away and if you can reach someone who has the other "remote" for your car, you can unlock the doors.

-------------------------------------------------------------------------
I could not check this system, But You can try it for a moment. I think It will be working well.

Try...........

Tuesday, February 5, 2008

Mobile Communication & Our Health

I Reseved This Message as a E Mail.I think It will be important for you too...!

Please read....................................

MUST READ!


Where do you keep your Handphone normally? This morning I heard a true and sad story from a Friend of mine. She told me one of her friends is always having miscarriages. When the baby gets to be 2-3 months old she loses it. This happened several times over. The couple went to check with many doctors and at last one of the doctors examined the dead baby and found that the baby's body cells kept dying asthe baby was growing in the womb until he/she could not survive.This was because her uterus was affected by HANDPHONE RADIATION. The doctor told her she now has no chance to give birth to a healthy baby because the radiation has affected her uterus so that the major portion of the cells in her uterus have already died. This happened because she has been keeping her handphone in her working jacket so that the phone rested against just the right s! pot for the uterus. She had been wearing it like this for a few years. Please beware of this and take note if you don't want what has happened to this woman to happen to you.
Dearest family members,
Please do not ignore handphone radiation which will damage our health or body organs. Please put away your handphone when ever you don't need it much .
Guys,
Please do not keep your handphone near to the kidney position and pants pocket as this will damage your genital area and affect your ability to father a baby. The other doctor also advised another friend to keep her handphone away from her new born baby to avoid radiation damage to the baby's brain cells. Do not let the baby or toddler play with the handphone for a long time. This is because the small young baby or toddler is still very fragile and growing, so he/she is much more vulnerable to radiation damage. Please remember not to sleep together with your handphone or put it next to your bed. Keep any other electronic goods (such as tvs) which also give off radiation away from your bedroom to reduce risk as we have to sleep a few hours every day in our bedroom at night. Further, do not imagine that if you switch off the TV there will be no radiation. Actually it is still around in your room. It is not advisable to have even a small digital alarm clock close to your head while sleeping.
Take Care of yourself and your loved ones.
Thank you

Wednesday, January 30, 2008

Television



Principle of Operation of cathode Ray Tube ( CRT)




Thermion Emission




A hot cathode is used to produce a supply of electrons. This may consists of a fine tansand wire or filament which is heated to high temperature .Metals content free electrons if the temperature of the metal is raised, a thermal velocities of the electrons will be increased.


A hot cathode is used to produce a supply of electrons. This may consists of a fine tansand wire or filament which is heated to high temperature .Metals content free electrons if the temperature of the metal is raised, a thermal velocities of the electrons will be increased.






The chance of electrons escaping from the attraction of the positive Irons will then also be raised. Therefore by heating a metal to a high temperature electrons can be boiled off. This is called Thermion Emission.


Once an electron escaped from the cathode it is subjected to a retarding force set up by the negatively charged electrons that have already escaped. An electron is slowed down by this force and may be return to the cathode an emitted electron can also be slowed down by coming in to collision with gas molecules. To minimize this effect cathode is placed within an evacuated glass envelope.






Electrons are continually emitted from the surface of a heated cathode. There are subjected to forces which tend to return them cathode. The cathode is surrounded by a cloud of electrons. The cloud of electrons around the cathode is known as the space charge. Space charge is negative.If another electrode the anode is introduced into the evacuated space and is maintained at positive potential with respect to the cathode it will exert and attractive force on the emitted electrons due to the influence of that attractive force electrons are rapidly accelerated to the anode.A value with just a cathode and anode is known as a diode. A triode has a third electrode known as the control grid inserted between cathode and the anode .the tetrode value has another grid inserted between the control grid and the anode. The pentod value has three control grids.

Monday, January 28, 2008

Network overview

Network overview

What is a network?


A network is a system that transmits any combination of voice, video and or data between users.

A group of connected computers that allow the sharing of information and equipment, such as printers.

Networks can interconnect by other networks and sub networks.A computer network interface card installed.

Computer with network interface card installed.

The network operating system (Ex. windows NT/2000/2003) on the user’s PC client and servers.

The cables connecting all network devices (UTP cables with RJ-45 jacks).

All supporting network components (h..bs, routers and switches, etc)(UTP-Unshielded twisted pair, RJ-Registered jack)


Types of computer networks


Local aria network (LAN).

Metropolitan area network (MAN).

Wide area network (WAN).


Element of a Small LAN


Computers with network interface card installed.

Hub/switch.

Cabling (UTP cables with RJ-45 jacks).

Network operation system.

Local Area Network (LAN)


LAN is the most common type of network found in businesses. LAN’s connect computer and devices located close to each other, usually within the same building. Typically, LAN’s connect no more than 100 computers.

Metropolitan Area Network (MAN)


A collection of local area networks located in the same geographical area, such as city or town.


Wide Area Network (WAN)


Wide area networks generally cover a large geographical area. Connects local and metropolitan area networks that may be located throughout the country or around the world.


The Hardware used on Computer Network


• Hubs

• Switches

•Bridges

• Routers

• Gateways

• Repeaters

• File severs

Hubs
Hubs are the central connectivity point in a star network, work group or subnet. It’s primary function is to receive and send signals along the network between the device connected to it. All communication across the hubs “broadcast” to all connected nodes.


Switches

Switches connect all computer LAN connections, same as the hubs. The difference is that switches can run are able to direct and filter information to and from specific designation.


Bridge
Bridge are used to connect (separate work groups together) two or more network segment together, so that equipment on the network can communicate.


Routers
Routers are able to route and filter information to different network.

Gateways
A gateway is a network point the act as an entrance to another network. The computers that control traffic within the network or at the local internet service provider (ISP) are gateways.
RepeatersA network device that regenerates signals so they can extend the cable length. They do not change any information being transmitted and they can not filter any information.

File severs

A high capacity disk storage computer connected to the network that contains files/applications and shares them as requested the other computers on the network.

Sunday, January 27, 2008

Simple Telecommunication System

Network Hierarchy

IC – International Centre
BC – National Centre
TC – Tertiary Centre
SC - Secondary Centre
PC – Primary centre
LE – Local Exchange (Central Office)


The public telephone system consists basically a large number of single telephones unevenly distributed through out of the country, each one being connected to a switching centre called telephone exchange. Each exchanges has lines to other exchanges and also to a suitable positioned main switching centre which in turn has access to all the other main switching centre in the system.Thus, any telephone connected to an exchange can be connected, at will, to any other telephone in the country and by using an international switching centre, to any telephone in the system of any other country.In some countries the Local Exchange is known as the Central Office.

Local Battery (LB)

A local battery powered all the original telephones. This was because the transmitter needed power and the local battery provided the right power irrespective of the length of or bad external wiring.because the batteries were installed in customer premises. This was a major expense for the maintenance team. original batteries xxxere wet cells which could leak and these were letter superseded by dry cells.

Central Battery ( CB)

The ‘LB’ system was superseded by the central Battery System which used a large set of battries at the local exchange and this became possible because of saving made by economics of scale.

‘CB’ Working

Advantages

Easy to maintainInstallation and maintenance cost lost


Disadvantages

Limitations(Distance for line providing)

Mobile Radio and Cellular Telephone Systems

Private Mobile Radio

(PMR) or as it sometimes called professional mobile radio is widely used for businesses as very convenient way of communicating.It typically refers to sophisticated radio trucking services that provided two way mobile radio communications for mobile users to connect to PMR voice and telephony and data networks. There are a wide variety of such systems, for example.PMR offers a two-way communications service. Permits users to talk over a short distance on a simple local system or wide-o complex system, without incurre any costs on the calls made no matter how many or for how long.


Background to private mobile radio (PMR).

PMR is the oldest of mobile communication it has been in used for over 70 years. It is used by many taxi and courier firms, security guards and utility companies. Many rural businesses choose the PMR option, because they find that thy simply do not have mob phone coverage, or they are in an as where the network frequently goes down. Initially the PMR systems consisted of a base station whit a number of mobile stations, communication used a singe frequency, with simplex push to talk transmission.


What determines the range of the radio?

The power of the radio transmitter is one of the main factors in determining range.
Hand-portable radios are limited to 5 watts ERP (radiated power from the aerial), whereas the power allowed from some mobile (vehicle-mounted) radios is 25 watts ERP. Height is another important factor, as the higher the radio waves can travel unobstructed. Under ideal conditions, a PRM radio signal may be received up to 3Km away; a professional handheld up to 5Km; and a vehicle mounted up to several tens of kms. With the addition of repeater systems, the coverage can be extended to an entire country!