Author : William LawThe term random wire antenna is often misused by radio buffs and is often misunderstood, even by licensed and qualified ham radio operators with a few years of hobby radio experience

If you are only listening to shortwave radio broadcasts on the HF radio bands, then a few feet of electrical wire thrown out of your window or strung along the top of your roof or garden someplace will certainly capture a lot of radio signals and route them into your shortwave radio receiver However, the results you get won’t be particularly good They will be unpredictable or, you’ve probably guessed it, they’ll be a bit random

Your radio listening efforts will be much more successful if the length of your wire antenna is cut to suit the wavelength (or frequency) of the radio signals that you are most keen to listen to And once you cut the antenna for a specific wave band, it is no longer a random wire antenna It is a tuned antenna or a resonant antenna

That means your wire antenna is in tune or adjusted for the radio signals you want to hear, just like a tuning fork helps you adjust a musical instrument And when your wire antenna is in tune with the signals you want, it is harmonically-related to those signals and it captures them more effectively for you to listen to

That’s fine for short wave listeners (often referred to as SWLs), because their interest is to receive radio signals rather than transmit them Although many serious SWLs get interested enough in two way radio signals to do a little studying and get an Amateur Radio license, which allows them to transmit signals as well That makes them Radio Hams And Ham Radio or Amateur Radio (its official name) is really a big fraternity out there, with members male and female, of all age groups, all over the world

For transmitting radio signals, the antenna must couple to the radio transmitter so the RF amplifier sees an impedance of 50 Ohms, or very close to it Otherwise the transistors in the RF amp can burn out, which is a costly repair job Many modern 2 way radios now have a special circuit to sense this mismatch They shut the transmitted signal right down to a tiny amount to try and save the transmitter That’s good for the radio, but no good for you if you want anyone to hear your signal Chances are it will be much too weak to be heard properly

In this case, many radio operators (both Amateur and professional) use an antenna tuning unit (or ATU) between the radio transmitter and the aerial This fools the radio into seeing a 50 Ohm load, so it puts out its maximum transmit power Unfortunately much of that power gets lost or wasted as heat, either in the ATU or in the cables between the radio and the random wire antenna So it is always much better to use an antenna that matches the band you will be working with that radio You can read more about antennas and two-way radios here at Walkie Talkie Two Way Radios and Business 2 Way Radio

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Author : David EnglishThere are many reasons why you might need to purchase self recording spy cameras Do you want to keep a close eye on the cash till in a small store or restaurant to see if any of your employees are stealing extra cash? Are you feeling nervous about how your babies are treated while your at work? Maybe you suspect someone has been snooping around in your office when your not in

Having a self recording spy camera in your home, office, or small business can provide evidence for theft of information, personal valuables, or important documents, as well as insure that you have the best nanny for taking care of your baby

Give Yourself Piece of Mind with an Exclusive Look at What goes on When Your Out

According to reports, the number one use for self recording spy cameras is as a nanny spy camera If you follow the news on the subject, you probably know why Spy cameras have repeatedly caught hired caregivers neglecting, shaking, hitting and otherwise mistreating children entrusted to them It is difficult to know who can be trusted in the child care profession, that is why the trend of nanny-watch cameras is growing

Much of what is recorded by self recording spy cameras is not abuse, but there is more abuse happening than what is caught on video Unrecorded abuse can more easily turn tragic

A young mother who left her child in the care of a friend while she went to a college class to take a quiz found out the hard way, he couldn’t be trusted She called after the quiz to ask how her precious little girl was doing

The friend told her that her baby girl was not breathing right She hung up the phone and called 911, but it was too late The damage was done, just days later her precious little one was gone The doctors diagnosed her little girl as a victim of shaken baby syndrome

If there had been a self recording spy camera in the room at the time of this fatal abuse, this young woman’s baby girl probably would have still died, but if prior self recording spy camera evidence suggested that this friend was not truly trustworthy, she might not have suffered that fatal abuse

Not every care provider will neglect or abuse your child, but using spy cameras can help you make sure you have the best care for your child possible

Sure You’ve got a Good Nanny? Use the Camera to Catch up on What You Missed

It is hard to leave your baby at home with a nanny, not only can you use a self recording spy camera to make sure your baby is unharmed and happy, but you can also use the footage to catch up on what you missed while you were at work

Some providers even encourage the use of a camera for this purpose, so if your worried about spying on your nanny tell her ahead of time that you plan on using a hidden camera, if your nanny doesn’t approve, hire one who will

Why Buy A Self Recording Spy Camera?

You may think a cheaper spy camera would do the job, but before you decide, you ought to know the advantages of having a self recording spy camera Just a few years ago having a spy camera meant you needed at least three components, and a more complicated setup

Self recording spy cameras, also called self contained spy cameras, come with all the components you need to record already inside the device All you have to do is plug it in, or in some cases insert batteries, and your good to go

As an added bonus, most self recording spy cameras are motion activated and can be programed to record at specific times of day or have a certain area masked to make sure your dog or cat doesn’t trigger the camera to record unnecessarily If you already have a security camera, you can say goodbye to sifting through hours of uneventful footage when you choose to invest in one of the new self recording spy cameras

Easy Placement with Non-Suspicious Objects

Self recording spy cameras are designed to look like a variety of everyday objects You can buy a self recording spy camera in the form of a CD player, plug in air freshener, wall outlet, wall clock and more Self Recording Spy Cameras come in almost as many forms as the cheaper variety Plus, the extra features make them an excellent choice for your hidden surveillance needs Give yourself a little piece of mind, and get one of these self recording spy cameras today.

David English owns Marshall Self Defense. A one-stop-shop for all personal security and surveillance needs.

For more info visit: http://www.marshallselfdefense.com/self-recording-spy-cameras.htm

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Author : Roberto SedyciasAs time passes, technology takes a leap too What is new now may soon go outdated Mobile phones are a rage and they have become an inseparable part of human existence Today, we cannot imagine being without our cell phones even for a day The one most important thing a mobile phone does is connect us with everyone around us

More than that, a mobile is also capable of providing entertainment and even help work The new mp7 cell phone is a nice example of the present day`s mobile phone The gadget comes with a variety of features to match the needs of tech-savvy mobile users

Features of the mp7 cell phone:

It is difficult all the features you want in one phone This is one phone which gives you a good mix of work and play The mp7 is a GSM enabled cell phone It works on most GSM frequencies The mp7 mobile phone has a memory slot for videos, pictures and music It leaves the mp3 player phones far behind and is a perfect device for music lovers

The mp7 cell phone is similar to the much coveted iphone It has a 320X 240 attractive display screen The touch screen is the latest offering that makes using a mobile phone even more attractive and interactive The touch screen feature brings the user closer to their gadget while operating it

It has an in-built FM tuner and even a mobile TV tuner in the mp7 format So wherever you go, you never fall short of entertainment If you want to watch news you can do it anywhere and whenever you want This strongly appeals to the TV lovers who cannot afford to miss TV for anything

Mobile phones having cameras are doing away with the need to carry a separate camera The new mp7 cell phone has a 1 3 pixel camera that gives good quality pictures The pictures are clear enough to showcase your memories

The phone is equipped with Bluetooth to carry out easy transfer of pictures, videos and music Bluetooth is an essential tool that helps personalise the phone and share ringtones, pictures and wall papers Bluetooth helps ease of transfer It allows you to customise your phone as per your likings

Buying the mp7 cell phone:

Before you buy the mp7 cell phone check its features Read up as much as you can on online sources or magazine The best to do is to visit a mobile phone shop and see the phone for real Ask a friend who is already using an mp7 cell phone

The phone is not very expensive Hence it is not high money at stake So if you wan to have a phone that provides you maximum features and you want to try the touch screen too then you can consider the mp7 cell phone If you like to change your mobile phones according to the technical advancements then going for the mp7 cell phone is not a bad idea Before you buy the phone wait for a day and check if this is what you want You can have access to portuguese articles about cell phones from page Cell_Phone

Roberto Sedycias works as IT consultant for Polomercantil

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Author : Bercle GeorgeWe know that solar energy is a good renewable energy resource and that we should start to utilize it more especially when the Earth’s fossil fuel reserves are slowly dwindling and will run out in 30 to 50 years We better look at the various alternative energies and begin a fast tracking of development to hasten our independence on non-renewable fossil fuels And solar energy is as good as any other alternative energy resource out there However, several arguments against solar energy have been raised through the years But probably the most convincing argument is the high costs of solar energy utilization

The problem with solar energy is that you can only harness it during the daytime And even when the sun is up, the sunlight will be interrupted by occasional cloud covers, rains, fog, and even smog So in order to harness the sun’s energy we need equipment that can get as much solar power as possible at a given time and we need some way of storing that energy so we can use them without ay interruptions

We do have the technology to harness the sun’s energy, convert it into usable electricity, and store them for future use And that technology itself is the primary reason why solar power has not caught on even today The process of making solar panels as well as the technology for storing that harnessed power remains to be quite expensive

The good thing about this fact today is that due to the recent increase in the costs of fuel and gas, solar power is no longer a far fetched alternative The gap between the costs has gone down considerably and hopefully in the near future, the costs of solar energy production will be quite competitive

Furthermore, the costs of photovoltaic cells are indeed quite expensive that contemporary oil and gas equipment But one of the flaws of the argument of costs is that people tend to limit their perspective of solar energy as to only referring to photovoltaic cells There are other means of harnessing solar energy and not all of them are as expensive as PV cell manufacturing

One way of getting the sun’s energy and converting it into usable electricity is the concept of solar thermal plants In solar thermal technology, various solar collectors are utilized to generate heat which can be applied from the simplest heating and ventilation of houses to the production of massive amounts of electricity The use of mirrors or lenses to reflect sunlight to towers equipped with liquids that heat up and produce steam The steam then turns turbines which in turn generates the electricity needed

The process adds another step compared to photovoltaics which converts solar energy directly into electricity Nevertheless, solar thermal systems of power production is cheaper that the production of PV cells For a larger consumer market, it seems that solar thermal energy is the way to go

Regardless, the point here really is to emphasize that solar energy has more to offer The cost of production is a valid argument against solar energy but still there are ways around it Costs can be minimized by using other techniques of harnessing solar energy or future developments in the field of science and technology will produce products that are more cost efficient that what are available today For more on science, technology, energy and more visit :
science and technology

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Author : Thomas PrettyIncreasingly the world is going green As ominous news of climate change and rising sea levels seem to fill our newspapers and bulletins it is quite clear that an environmental focus is becoming evident in many walks of life One of the industries that is rapidly embracing a green agenda is the technology industry This is especially evident in the manufacturing of televisions, nearly every company is now marketing a green LCD TV, one that is better for the environment from the outset, across fields such as materials, manufacture and power usage

One of the latest LVD TV models to incorporate eco thinking in its design is the new Sony Bravia range The range contains six models and the majority of these have been awarded the “EU Flower”; an award that acts as proof of eco credentials It is hoped that this range will use around twenty to thirty percent less power than those of the previous range The top models are even purported to use around fifty percent less power Another benefit of this new Bravia range is the introduction of a presence sensor This technology detects when people have left the room and then switches the LCD TV to picture off mode, switching itself back on when someone enters the room Such technology is hoped to considerably cut power consumption

It is not just the new Sony Bravia range however that has enrolled in an eco agenda For the last year Sharp LCD TV models have been awarded the EU Flower for their impressive power consumption levels; the criteria for the award are based upon a low electricity consumption when in use, a standby power use of less than a watt and the use of materials that are more easily recycled It has become the case that nearly all LCD TV manufacturers have started to embrace the EU Flower as an important marketing tool Samsung are looking to the future utilising LED rather than LCD technology, this can hopefully result in a TV that uses forty percent less energy

One of the outcomes of this increased eco focus has been that the plasma TV has been somewhat abandoned as a form of technology The primary reason for this is that plasma technology requires far more energy to produce an image than either LCD or LED Some estimates place this at around twenty percent When taken for the lifespan of a TV, approximately forty thousand hours this twenty percent surmounts to a considerable amount of energy

While LED or OLED, as it is being termed in the industry, promises much in both viewing experience and energy consumption it is at the moment a technology in its infancy The largest OLED screens are currently only fourteen inches across, although the fact that they are extremely slim, light and produce an unbelievable picture, all with excellent power consumption has led many to believe that they are the future of TV manufacture

Until OLED TV technology is developed further however consumers must make the choice between LCD and plasma If the decision is to be based on green credentials, LCD is easily the best choice The latest technological advancements have made the LCD TV a green alternative to the wasteful televisions of old Technolgy expert Thomas Pretty studies the increasing environmentally focus of the new bravia lcd tv range and why Sony are wholly embracing an eco focus.

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Author : Bercle GeorgeThere are lots of interesting facts about solar energy Educating yourself about this will prove to be beneficial in the long run You can share the information to your loved ones You can teach them of ways on how they can help to conserve the energy You can also do your share to help this method to advance if you are a genius in the field But if you are an ordinary citizen who only wants to enjoy, then feast on But remember that you also have responsibilities to the environment that you must accomplish in order to do your part in the whole scheme of things

The Facts that Matter
1 Solar radiation makes it possible for the energy coming from the sun to be used as power source and energy that can in turn be used for many purposes The technology on this aspect is characterized in two ways They can either be passive or active This will depend on the methods that are used to get, convert and allocate sunlight

What are active solar techniques? These utilize pumps, photovoltaic panels and fans to renovate sunlight into useful resources These aim to increase the energy supply that is why these can also be referred as supply side technologies The passive solar techniques, on the other hand, use only selected resources with constructive thermal properties, utilize the kind of spaces that can circulate air naturally and apply the position of buildings and structures towards the sun These will lessen the need for other sources and can also be referred as the demand side technology

2 Solar energy has influenced many factors that surround people This can be referred in planning and designing buildings This process can be rooted back at the early days of the architectural history The Greeks and the Chinese first used such factor in building and constructing their architectural pieces and on their planning methods

3 Solar energy is also being utilized by the agricultural sector because they rely heavily on its benefits in order to gain more harvest They developed ways in order to plant the kind of crops that will grow according to the amount of sun that they will be getting for the season This can also be used to dry the crops, pump water, brooding of chicks and to dry animal manures that can later be used as fertilizers

4 On seasons like the Little Ice Age, fruit walls were used by French and Chinese farmers to be able to collect and store solar energy to help them keep the plants warm and to speedy up the process of ripening of fruits These walls serve as the thermal masses The fruit walls that were first developed were perpendicular to the ground and faced the south direction Over time, innovations were done and slopping walls were used to gain more advantage from the sun

5 To convert the solar light into heat, people have developed greenhouses These enable the production and cultivation of specialty crops all year round Such innovation made it possible for crops to be produced in untimely seasons and in places where you think that those plants won’t grow

And these are only some of the interesting facts about solar energy These give you a good peek at how wonderful nature is and how people have developed ways to use it to advance in many aspects of their lives For more on science, technology, energy and more visit :
science and technology

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