BASIC TERMINOLOGY USED IN ELECTRONIC communication

BASIC TERMINOLOGY USED IN ELECTRONIC

COMMUNICATION SYSTEMS

By now, we have become familiar with some terms like information source,

transmitter, receiver, channel, noise, etc. It would be easy to understand

the principles underlying any communication, if we get ourselves

acquainted with the following basic terminology.

 (i) Transducer: Any device that converts one form of

energy into another can be termed as a transducer.

In electronic communication systems, we usually

come across devices that have either their inputs

or outputs in the electrical form. An electrical

transducer may be defined as a device that converts

some physical variable (pressure, displacement,

force, temperature, etc) into corresponding

variations in the electrical signal at its output.

(ii) Signal: Information converted in electrical form

and suitable for transmission is called a signal.

Signals can be either analog or digital. Analog

signals are continuous variations of voltage or

current. They are essentially single-valued

functions of time. Sine wave is a fundamental

analog signal. All other analog signals can be fully

understood in terms of their sine wave components.

Sound and picture signals in TV are analog in

nature. Digital signals are those which can take

only discrete stepwise values. Binary system that

is extensively used in digital electronics employs

just two levels of a signal. ‘0’ corresponds to a low

level and ‘1’ corresponds to a high level of voltage/

current. There are several coding schemes useful

for digital communication. They employ suitable

combinations of number systems such as the

binary coded decimal (BCD)*. American Standard

Code for Information Interchange (ASCII)** is a

universally popular digital code to represent

numbers, letters and certain characters.

(iii) Noise: Noise refers to the unwanted signals that

tend to disturb the transmission and processing

of message signals in a communication system.

The source generating the noise may be located

inside or outside the system.

(iv) Transmitter: A transmitter processes the incoming

message signal so as to make it suitable for

transmission through a channel and subsequent

reception.

(v) Receiver: A receiver extracts the desired message

signals from the received signals at the channel

output.

(vi) Attenuation: The loss of strength of a signal while

propagating through a medium is known as

attenuation.

* In BCD, a digit is usually represented by four binary (0 or 1) bits. For example

the numbers 0, 1, 2, 3, 4 in the decimal system are written as 0000, 0001, 0010,

0011 and 0100. 1000 would represent eight.

** It is a character encoding in terms of numbers based on English alphabet since

the computer can only understand numbers . Jagadis Chandra Bose

(1858 – 1937) He

developed an apparatus

for generating ultrashort

electro-magnetic waves

and studied their quasioptical

properties. He

was said to be the first to

employ a semiconductor

like galena as a selfrecovering

detector of

electromagnetic waves.

Bose published three

papers in the British

magazine, ‘The

Electrician’ of 27 Dec.

1895. His invention was

published in the

‘Proceedings of The Royal

Society’ on 27 April 1899

over two years before

Marconi’s first wireless

communication on 13

December 1901. Bose

also invented highly

sensitive instruments for

the detection of minute

responses by living

organisms to external

stimulii and established

parallelism between

animal and plant

tissues.

 (vii) Amplification: It is the process of increasing the amplitude (and

consequently the strength) of a signal using an electronic circuit

called the amplifier Amplification is

necessary to compensate for the attenuation of the signal in

communication systems. The energy needed for additional signal

strength is obtained from a DC power source. Amplification is

done at a place between the source and the destination wherever

signal strength becomes weaker than the required strength.

(viii) Range: It is the largest distance between a source and a destination

up to which the signal is received with sufficient strength.

(ix) Bandwidth: Bandwidth refers to the frequency range over which

an equipment operates or the portion of the spectrum occupied

by the signal.

(x) Modulation: The original low frequency message/information

signal cannot be transmitted to long distances because of

reasons. Therefore, at the transmitter,

information contained in the low frequency message signal is

superimposed on a high frequency wave, which acts as a carrier

of the information. This process is known as modulation. As

will be explained later, there are several types of modulation,

abbreviated as AM, FM and PM.

(xi) Demodulation: The process of retrieval of information from the

carrier wave at the receiver is termed demodulation. This is the

reverse process of modulation.

(xii) Repeater: A repeater is a combination of a receiver and a

transmitter. A repeater, picks up the signal from the transmitter,

amplifies and retransmits it to the receiver sometimes with a

change in carrier frequency.

paypal fraud

hacking calling cards

hacking calling cards


hhhmmmmmmmmmm yesss hacking calling cards!!!!1




Phreak codes are fast running out,
and people are getting caught. Its
time to pioneer a brand new industry.
So far I think this file is original,
so I am writing it.

Most, if not all people have calling
cards from AT&T. They can be used from
any phone to dial long distance and
charge it to your AT&T bill. The
objective, to use someone elses card to
get free long distance service. These
codes are not traced, and they are only
FOUR digits! The nice part is you can
hack the code for anyone you like and
attack a specific person, not a random
name like when hacking MCI. Take your
worst enemy, when you know his phone
number, its the end...

Format:
a. Dial 0.
b. Dial phone number with area code.
c. Wait for tone.
d. Dial billing number with or without
area code.

If your code is correct, the fone
will ring. If it is not correct a
recording will say "Please dial your
card number again, the card number you
have dialed is invalid". You can try
another four digits but after that it
will tell you to call AT&T if it is
still invalid.

This is more of a pain to hack
because there are a thousand possible
codes for each phone number. Just
make a short basic program to do the
job of dialing all the codes. its
best to do a random scan instead of
sequential in my opinion.

CABLE TV SCRAMBLING TECHNIQUES

CABLE TV SCRAMBLING TECHNIQUES
-------------------------------------------------------------------------------
There are 4 major methods of pay-channel security and each has different
consequences for cable ready receivers. The 4 systems are jamming, trapping
out-of-band scrambling and in-band scrambling.

Jamming:
A jamming signal is placed between the picture carrier and and the aural
carrier of the secured channels. The cable operator supplies a filter for
each customer for each paid channel. This type of security is easily defeated
by homemade notch filters.

Trapping:
In these systems frequency filters are installed in line with the cable
drops on telephone poles. The traps are removed for customers paying for the
premium channels. Cable-ready TV's work fine in these systems.

Scrambling - The gated Sync Methods:
Scrambling in the cable TV business still generaly means pulsed sync
suppression. In its simplist form, amplitude of the picture carrier is reduced
by 6 db during the horizontal blanking intervals and sometimes during the
vertical blanking intervals. The resulting video signal has sync tips between
the black and white levels. Sync seperators in the set cannot operate properly
with this signal, nor can AGC and color circuts, so the picture is scrambled.
The decoder compensates by antennuating the signal during the time in which
the transmited signal was not antennuated. In order to accomplish this, the
logic controlled gain switch must get timing information. In-band systems
transmit pulses as amplitude modulation of aural carrier or a seperate carrier
in out of band systems.

Out of band scrambling:
The usual setup is that the decoder is connected directly to the cable
ahead of the channel converter. Decoding is done at the pay channel frequency.
The decoder is likely to be in a seperate box, added to an old system to
provide pay channels. The box consists of a simple receiver (90-120mhz) for the
out-of-band data carrier and a broad band 6db gain switch. There is provision
for several scrambled channels, each which has a different data carrier.
This system is directly compatable with cable ready receivers. Without the
cable converter, the decoder is connected to the TV. Tuning and remote features
of the TV are preserved with the only inconvience being the need to operate the
switch on the decoder when changing to and from any scrambled channel. Out-of-
band systems tend to last until the operators using them rebuild to provide for
a large increase in the number of channels.

In Band Scrambling:
In this system any number of the available channels can be scrambled.
Because the data carrier for each scrambled channel is its own aural carrier,
only one data receiver, at the aural carrier frequency (eg. ch 3) is required.
The decoder detects the presence or absense of data automaticly switching
itself in or out. The converter-decoder box can be hardwired to decode just the
channels ordered, using a prom like device. Alternatively, the transmitted
channels can be "tagged" by time division multiplexing binary tag (program
identification) data with the sync data on the aural carrier. The decoder
boxes can be wired for "tiers" (groups of programs the cable operator sells
togeather) rather than fixed channels, giving the operator more flexibility.
The decoder boxes can be "addressable". These boxes have a seperate out of band
data channel for data from the head end. Each box has a serial number burned
into its logic or otherwise available to its logic circutry, and its channel
or tier authorization stored in volatile ram. A computer at the headend
periodicaly addresses all decoders in the system individualy and loads each
with the channel or tier capacity ordered by the customer. The need for house
calls is reduced, PPV (Pay per view) is possible, and missing boxes cam be
turned off, rendering them useless for premium channel viewing. Some but not
all of these features can be programmed into out-of-band systems.

Aside form their ability to generate sync pulses, thus foiling the scrambling
system, cable ready TV's have presented another dificult problem for in-band
systems. Because the decoder operates at the converted channel, a channel
converter is required ahead of it. Wheather the TV receiver is cable-ready or
not, it operates only at the converted channel, wasting the tuning and remote
control features.

meditation

Meditaion is infact concentrating on the self .The term is used in general sense to denote practise of any technique for interiorizing the attention and focusing it on some aspects of self.It is the seenth step of the eightfold path of yogaBehind the light in every little buld is a grat dynamic current :bebneath every litle wave is the vast tdynamic current .SImilarly behind his succesful human lies his infinite self.Realization of self is what we call enlightment  and the process  to gain it is what we call simply MEDITITATION.Remember taht YOU is the profilic source of all the pwer and  the everyday YOU  is only a fragment of that which can b manifested..The reall you is infinte inits potentilaity.by concentratioin within  you can dfell teh divine bliss of your soul within.You cannot se your real image in ruffled water ot in moving water properly but when water surafe is calm you can see the real you.Through meditiaon we draw restless thoughts from the lake of mind ralizr that we are infinite.

Focus your attntion within.You will fell a new power ,a new strengt a new peace -in the body mind and spirit.Mines of poer lies unexplore withinyou.Hey my frens try to explore it.Sleep is on unconsious meditation but  meditiaon is consios sleep.In Sleep you have limited cosmic energy but in meditioan you have abundant cosmic enrgy.

Meditation makes you rise above suffering . A real meditator never really hangs on to the questoin>>Why should this happen to me? Instead he thinks every trieal as pickax  with wihch to dig tinto soil of your conssiouness and release the foundation of the strenght of within.

You heighten your misery by imagintaion.Worrying or feleling sorry for yourself wont ease your pain but rather increase it.The more yout hink on it the more you magnify it.But if you are a meditator then you dont peek on the situtaion yu infactdirectly getmixed to your self.And beleive me your slef is infinte.You know it wahtever added to ininte is infinte nad whatever goes out og it is still an infinte .SO u become abocve the sufferingsbecause you  are infinite.Th

The joy of god is boundless unceasing ll theitme .Body,mind nothing can disturb you when you are in consiosness

Meditation is the vision of your inner being ,the sight of your soul the telescope of your heart .Meiditation is a balance of calm ntelligence and purity of heart.Emotion is the distorted feelings that will lead you wrong way.ourr heart is our power but today we have become slave of it.Our heart wants we must to id.Our consciece saysits wrong butstill we do it because we are slave of heart.Who doesnt kno killin is wrong?Who doesnt know hate is bad.But still why people kill or why we hate..because we are still under heart.Imagine if you win the world you may not b the real emperor but if you win yourself you are the real emperor.

Be silent abd calm every night for at leat an hour preferably much longer before you retire and again in the norning before starting the days activity.Thia will produce an undaunted unbreakable inner habit of happiness that will make  you able to meet all the tryoing situtation of the everyday batle of life.

Well during medititation you clsoe your eyes but our heart will flow.Today you go and try you will realize how much layers of thoughts you have in you mind which has finnaly covered your realness.When a rocket is lauched into space a more extra energy is required to penetrate  the earth gravitation field but after it crosses it the gravittion of the moon slowly but automatically pulls you.Similarly when you are meditind you are jsumping from body pheripheri to mind and from mind to inteellect At each state fo crossing the field of body r mind you will need an sxtra effort cause you mind and heart feeds you at that time with unknown questions and useless thinkings.You apply extra force penetratee it .after you cross the level the mind consioness auotmatically attratcs you.

Meditation is not a concentration .You may have a question if there is any difference between meditiaon and concentration.well concentration is done being withd the senses and medittiaon is done being beyond the senses.One should know the scientific meaning of concentraion.By the power of concentraion man can use theunhold power of mind to accomplish  that waht he desires and he cna guard all doors through whihc failures may enter.many people think to acheive they must do act slowly but know you give your full to it you can achieve it.

always centre you whole mind on wahtever you do,however small thinfg it may be/Also leanr to b flexible so that you can act immediately if needed.But do things with hundred perscent attention.

Most ppl think hafl heartedly.They only us e half heart. so that you dont have ower or succed.attain hundred percent to waht you do .that fulness is attained only through meditioan.

how to optimise blog for higher ranking in search engines.

blogging can be a measure to use up free time,gain knowledge and earn money.

Any newbies having a Gmail account can easily start a new blog using blogger platform and they can have their blog up and running within a minutes.  blogger  also provide you many templates for your blog. You can use either of the templates. All of them are free. You can post contents to it and can make it popular. Starting a new blog is not a difficult task but the real problem is getting traffic and for that you need to SEO ( Search Engine Optimization ). If you are completely new to the blogging world then you might not have heard about this word. However they are many bloggers who knows about SEO but still don’t know how to optimize the post in their blog. So if you are also one of them then this post might be useful to you.

What is SEO ?

SEO is acronym to Search Engine Optimization or Search Engine Optimizer. It is the process of improving the visibility of you blog in search engine results page

How to make your blog come on first page or top page on search engines

at first goto www.blogger.com and login your account. goto your dashboard  and click category button which seems like this as indicated by yellow arrow:

then click on settings and here you go...........!!! you will see the page as follows:

now when you see this page click on search preferences and you will see next page like this:

Now click on edit button next to description option and click on yes button to enable the search description . Search description means a short description about your blog. When any people searches about your blog then it will be appeared in the search engine result page. Give a suitable and short description about your blog and click on save changes button. 

it is done now...........your blog is optimized. Google will rank your blog in top pages when search category meets your blog contains.

Now click on create a new post button. In this post title , enter the title name of the post you are going to write. Next you need to write the contents about your post. The contents should be related to the post title name and it should be not less than 300 words. You should write quality content and it should be unique. If you do so you won’t be ranked in search engine page. Now in the right side click on labels button. Here you have to give the label name i.e category to which your post belongs to. It should be single word or sometimes two words and should be meaningful. After giving the label name click on done button. Now click on search description button. Here you need to write a short and suitable description about your blog post which you are going to post. After finishing giving a suitable description click on done button.


Now click on publish button and you have published your post which is fully optimized for better ranking in search engine result page.

You can also watch this video for more detail information.

FREE .COM.NP, .EDU.NP, .NET.NP .....................ALL .NP DOMAINS

  HERE YOUR search ENDS!!!!!!!!!!!!!

TODAY I AM GOING TO TEACH YOU HOW TO GET THESE DOMAINS ABSOLUTELY FREE.

hmmmmmmmmmm yes for freeeeeeeeeee
 merchantile communication,which is a leading company of nepal provides you free .np domains.
 for this first of all goto http://register.mos.com.np then select the domain you want to. remember, you can only make domain name from your citizenship name or from company name.
 now the screen appears like this:

when you choose a domain, you get notice of availability .remember that you can only make domain name of your name,then click register and again this page comes and you heve to fill the application form :

fill the form accurately and that must match with your citizenship document or business document.

In primary name server and secondary name server you have to enter the hostname provided by your host provider. Tertiary name server is optional. Note if you are going to host your domain in www.000webhost.com and www.host1free.com then you can enter the name servers as given below.

Name Servers for www.000webhost.com

Primary name server

Hostname : ns01.000webhost.com

IP Address : 208.43.152.32

Secondary name server

Hostname : ns02.000webhost.com

IP Address : 64.120.10.10



Name servers for www.host1free.com

Primary name server
Hostname : ns1.host1free.com
IP Address : 208.43.152.32 (Alternatively you can get IP address by pinging above hostname)

Secondary name server
Hostname : ns2.host1free.com
IP Address : 64.120.10.10

note that 000.webhost.com gives free hosting upto 1 gb space...........isn't is great guys???

if you donot know about hosting,then you can host in google blogger .

after you provide all information click in submission button and then you are doneeee!

 Now check your mail with the email you just used in the form. You will get mail from hostmaster@mos.com.np. Now you will need to submit a few documents in order to activate the domain.it may also take some days to get reply...be patience.

your email appears like this::

If you are running a Company or Organization then you will need

1. A scanned copy of an application letter written in the company/organization’s letter-head pad, stamped and signed by an authorized officer.
2. A scanned copy of the company/organization registration certificate issued by Office of the Company Registrar, Nepal.
3. A scanned copy to verify that annual tax of the company is being maintained.

If you want it for personal usage then you will need
1. An application letter in PDF or DOC format.
2. A scanned copy of the applicant’s citizenship or passport

After your documents are ready , reply to the same email from where you just got the message. Note : You should attach these documents before replying them and after attaching the documents reply them. It may take at least three working days to activate your domain. Please note that your request for this domain will be rejected if you are unable to provide all the necessary documents as stated above in this email. Once a request is rejected, you will have to follow the same procedure again to register for the same domain or a new domain. You should keep this email for your records.

enjoy your new domain!!!!!!!!!!

hydro electricity

The Hydropower Resource:
On Earth, water is constantly moved around in various states, a process known as the hydrologic cycle. Water evaporates from the oceans, forming into clouds, falling out as rain and snow, gathering into streams and rivers, and flowing back to the sea. All this movement provides an enormous opportunity to harness useful energy.

The United Nations estimates that the total "technically exploitable" potential for hydropower is 15,090 terawatt-hours per year, or 15 trillion kilowatt-hours, equal to half of projected global electricity use in 2030. Only about 15 percent has been developed so far. While much of the remaining potential may not be economically or environmentally suitable to develop, there are still significant opportunities for new development in regions like the former Soviet Union, South Asia, and South America.

Hydropower provides one-fifth of the world's electricity, second only to fossil fuels. Worldwide capacity is 776 gigawatts (GW), with 12 percent in the United States, nine percent in Canada, and eight percent in Brazil. When completed, China's Three Gorges Dam, poised to become the largest hydroelectric project in the world with 18.2 GW of capacity, will move China ahead of Brazil. Globally, hydroelectric capacity has more than doubled since 1970, and another 100 GW is currently under construction.

In the United States, hydropower has grown steadily, from 56 GW in 1970 to more than 95 GW today. As a percentage of the U.S. electricity supply mix, however, it has fallen to 10 percent, down from 14 percent 20 years ago, largely as a result of the rapid growth in natural gas power plants. In terms of electricity production, hydropower plants account for about seven percent of America's current power needs.

In some parts of the country, hydropower is even more important. For example, the Pacific Northwest generates more than two-thirds of its electricity from 55 hydroelectric dams. The Grand Coulee dam on the Columbia River is one of the largest dams in the world, with a capacity of nearly 6,500 megawatts (MW).

In addition to very large plants in the West, the United States has many smaller hydro plants. In 1940 there were 3,100 hydropower plants across the country, but by 1980 that number had fallen to 1,425. Since then, a number of these small plants have been restored; there are currently 2,378 hydro plants (not including pumped storage) in operation. These plants account for only a tiny fraction of the 80,000 dams that block and divert our rivers. As a result, there is a significant opportunity for growth according to the National Hydropower Association, which estimates that more than 4,300 MW of additional hydropower capacity can be brought online by upgrading existing facilities.

Worldwide there is a great deal of growth in small hydro projects. The World Energy Council estimates that under current policies, installed capacity of small hydro will increase from about 48 GW today to 55 GW by 2010, with the largest increase coming from China.More than half of the current global small hydropower installed capacity is in China, with plans to develop a further 10,000 MW in the next decade


Converting Moving Water to Electricity
In order to generate electricity from the kinetic energy in moving water, the water has to be moving with sufficient speed and volume to turn a generator. Roughly speaking, one gallon of water per second falling one hundred feet can generate one kilowatt of electrical power.

To increase the force of moving water, impoundments or dams are used to raise the water level, creating a "hydraulic head," or height differential. When water behind a dam is released, it runs through a pipe called a penstock, and is delivered to the turbine.


Hydroelectric generation can also work without dams, in a process known as diversion, or run-of-the-river. Portions of water from fast-flowing rivers, often at or near waterfalls, can be diverted through a penstock to a turbine set in the river or off to the side. The generating stations at Niagara Falls are an example of diversion hydropower. Another run-of-the-river design uses a traditional water wheel on a floating platform to capture the kinetic force of the moving river. While this approach is inexpensive and easy to implement, it doesn't produce much power. The entire Amazon River, if harnessed this way, would produce only 650 MW of power.

Another type of hydropower, though not a true energy source, is pumped storage. In a pumped storage plant, water is pumped from a lower reservoir to a higher reservoir during off-peak times, using electricity generated from other types of energy sources. When the power is needed, it is released back into the lower reservoir through turbines. Inevitably, some power is lost, but pumped storage systems can be up to 80 percent efficient. There is currently more than 90 GW of pumped storage capacity worldwide, with about one-quarter of that in the United States. Future increases in pumped storage capacity could result from the integration of hydropower and wind power technologies. Researchers believe that hydropower may be able to act as a battery for wind power by storing water during high wind periods.

There are a variety of turbines employed at hydropower facilities, and their use depends on the amount of hydraulic head at the plant. The most common are Kaplan, Francis, and Pelton wheel designs. Some of these designs, called reaction and impulse wheels, use not just the kinetic force of the moving water but also the water pressure.

The Kaplan turbine is similar to a boat propeller, with a runner (the turning part of a turbine) that has three to six blades, and can provide up to 400 MW of power. The Kaplan turbine is differentiated from other kinds of hydropower turbines because its performance can be improved by changing the pitch of the blades. The Francis turbine has a runner with nine or more fixed vanes. In this turbine design, which can be up to 800 MW in size, the runner blades direct the water so that it moves in an axial flow. The Pelton turbine consists of a set of specially shaped buckets that are mounted on the outside of a circular disc, making it look similar to a water wheel. Pelton turbines are typically used in high hydraulic head sites and can be as large as 200 MW.

The ability to meet power demand fluctuations is an advantage of hydro plants with reservoirs. Unlike run-of-the-river plants, which produce power around the clock, hydro plants with dams are typically used only when the power is most needed. Utilities save up the water, letting it loose only during peak times. Hydro plants, especially the large older plants built from the 1930s to the 1950s, are commonly the least-expensive source of electricity.