220 to 110 converter

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The first ever colour broadcast came to USA in 1953. This was based on NTSC – National Television System Committee standard. NTSC is being used by many countries in the American continent and as well as in Asia too, in countries including Japan. NTSC runs on 525 lines/frame. The Phase Alternating Line (PAL) system was introduced in early 1960s and was available in most European countries except France. PAL utilises a wider channel-bandwidth than NTSC, which provides a better picture quality. This system runs on 625 lines/frame. Sequential Couleur Avec Memoire or Sequential Colour with Memory (SECAM) standard was introduced in early 1960s and was implemented in France. SECAM transmits colour information sequentially but uses the same bandwidth as PAL. The standard runs on 625 lines/frame.

The reason for using these different standards is based on that the TV receivers require a source of field tinning reference signals to receive the images. At first it was thought that the Mains power supply frequency will be a good source for this field timing. This divided the world in two frequency zones, 50Hz and 60 Hz, which are the ones widely used in different countries. So, the TV standard was divided into 25 frames/second (50 Hz) and 30 frames/second (60 Hz). The designers slightly modified the 60 Hz category and converted it to 59.9 Hz, when they added colour to the signals. The main compatibility between the two categories of TVs remain related to be the field rate and this has not been solved as yet.

A solution had to be found to enable the TV to work on any of the standards available in the world.

This saw the introduction of a multi-system TV capable of working in a variety of video standards, such as PAL, NTSC and SECAM. This TV will work in almost all the countries in the world, with certain exceptions. Some parts of the world use a very rare video system which requires a special type of TV. These countries are – France Uruguay, Brazil and Paraguay. France broadcasts in SECAM-L, which is the only country doing so, while Brazil, Uruguay and Paraguay broadcast in PAL-M and N, which are not found in any other part of the world.

The question often arises whether my NTSC TV can be modified to PAL standard or other way round. The horizontal scan rates for both the standars are nearly identical – 15,734 Hz for NTSC and 15,625 Hz for PAL. Therefore this is not likely to be a problem. If these differed significantly, there would have been large cost issues coming into the design. The problem remains with the vertical scan, with 525 line/60 Hz NTSC and 625 line/50 Hz PAL. But its easier to modify the vertical deflection to accommodate a modest variation in rates.

As far as commercial multi-system TVs are concerned, there are not too many seen in U.S. because of lack of demand. These TVs are mainly manufactured for the international markets and are available in abundance in such places.

On the other hand, you can view all the standards of video inputs, viz., PAL / SECAM / NTSC, automatically. These are based on auto voltage sensors, switching from one main power of 240 volts, 50 Hz to 100 volts, 60 Hz, or vice-versa, automatically. Most of these TVs allow you to tune with cable or antenna channels in most countries in the world.

Different concept is followed in measurement specifications for multi-system TVs. In North America, the measurement is done only on the exposed screen of the TV, while in case of a multi-system TV, the encasing, covering the small edge of the screen, is taken into account. Although an American TV will be of the same size as a multi-system TV, the specifications would differ in the sizes of the two TVs as far as the screen is concerned. The screen measurement in a standard TV is done from the upper left corner to the bottom right corner of the screen.

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Normally, a multi system VCR permits you to play video tapes from all over the world, but is not capable in converting the video signals. Therefore, if you are using a NTSC system, a multi system VCR may not allow you to watch a PAL tape on your NTSC television. A converting multi system VCR is then required which will convert its video output signal through a in-built video converter, so that a PAL video tape could be played on an NTSC TV. With an ordinary multi system VCR, you will need to procure an external Tenlab video converter or a multi system TV. Normally these days the multi system VCR’s are being manufactured with in-built Video Converters. A multi system TV is capable of playing all the video formats like NTSC, PAL and SECAM.

On the same fundamentals, whether the video signals are in PAL, NTSC or SECAM, a multi system VCR will have the corresponding output.

Now the question arises, how will you view the tapes on your TV?

Well, there are a number of ways to execute this. As mentioned above, only a multi system VCR alone won’t be helpful. You will need to have a TV, which has either an in-built converter or an external one. Therefore, to watch a PAL video tape on a NTSC TV with your multi system VCR, the signal from the VCR need to pass through the signal converter before your TV can operate in PAL.

However, some multi system VCRs already have the video converter installed internally, and in this case, there is no need to purchase an external one. The disadvantage to these VCRs is that the image quality they produce is not as good as a multi system VCR and an external video converter combination.

The other possibility is the combination of a multi system VCR and a multi system TV. As discussed above, a multi system VCR only supports the type of signal coming in and does not have the capability of signal conversions. A multi system TV, with its inherent conversion capability, transforms PAL, SECAM or NTSC signals appropriately, would play the video tape in your multi system VCR. The disadvantage of such playing arrangement is that, converted copies of the video tape cannot be made. On he other hand, there are no video degradation with the combination mentioned above.

The final possibility is to get a multi system TV/VCR combo. This solution is not recommended because TV/VCR combos tend to be of low quality.

Common characteristics of Multi System VCR

A VCR needs only two video heads. to record and playback a tape, Additional heads are used for special effects, if any, such as slow motion, freeze frame, etc. Many manufacturers are going for modification in the video heads in different ways to improve the picture quality. Many VCRs now offer quick play from the stop point. There are also a huge number of VCRs that provide quick access from fast forward or fast rewind to visual scanning, and quick access from visual scanning to play. Many models now feature pre-programmed universal remotes with the ability to control TV and cable boxes. A universal remote will control the same brand of TV as your VCR.

Virtually all VCRs let you choose between two or three different recording speeds. Playback speed is automatically set, and even VCRs that record in only two speeds play back on all three speeds. Although, a faster-moving tape allows less recording time, it provides a better-quality recording. Because many people do time-shift recordings at the slowest speeds, some manufacturers, such as Toshiba, Mitsubishi, and Sharp, have developed special video heads (19-micron heads) for improved picture quality for recording and playback at the slowest speeds.

Many VCRs record an electronic index code at the beginning of each recording. To scan your recordings on a tape, you press index search. The VCR then stops at each index mark, and plays back a few seconds of the recording. Some VCRs even let you go directly to a specific index mark and start playback.

Allows you to search forward or backward through a tape at a range of fast and slow speeds. Jog control allows you to move the tape forward or backward frame by frame.

These models set their own clock thanks to a time signal being sent from your local PBS station. This means that you never have to set the clock initially or reset it after a blackout or brownout. When power is restored, the VCR will display the correct time. Auto Clock Set is now found on many mid- to upper-end models.

If you are buying a multi system VCR mainly to record television broadcasts, then programming is an important thought which should be given due importance. Except for VCPs (video cassette players), all multi system VCRs can be programmed at will to record at least one desired program. The most basic programming proposal uses a built-in clock timer that you set to start and stop within the next a 24-hour period. More complicated programming allows you to record several different programs on different channels or a period of 28 days or more (one manufacturer claims their machine will record eight programs over a 100-year period). Other program operations let you record the same program every day or every week. Many VCRs include VCR Plus+, a simple method of programming by entering a number listed in TV Guide or many newspapers’ television guides. Some VCR Plus+ models will also change channels on your cable box via a mouse, blaster, or an infrared transmitter located on the top of the VCR.

Another characteristic is the Hi-fi sound system that stands for high-fidelity, or high-quality sound. It is a new true stereo–not the low-pitched sound that was accessible on VCRs quite a few years ago. If you are thinking of taking a new VCR or even replacement, then certainly, hi-fi is the one upgrade feature that you should consider. All movies and videos manufactured now have hi-fi soundtracks encoded with Dolby Surround system.

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What is an LCD Display?

LCD is short for liquid crystal display, and while LCD technology has been around for quite some time, it has been only in the last decade or so that the technology became suitable for the high quality flat panel television and computer monitor displays we see today. The most notable feature of displays using LCD technology, of course, is the thinness of the unit, but the power behind that thin design is actually quite extensive.

The display on an LCD panel is comprised of picture elements, or pixels as they are known to computer geeks everywhere. The resolution the flat panel display is capable of is determined partially by how many pixels are contained in the display. A typical LCD panel display can range from hundreds of thousands of pixels to millions of pixels, and the higher the number of pixels the better the resolution will be. LCD televisions come in a number of different shapes and sizes, but they are typically designed to accommodate a 16 to 9 display ratio. This ratio makes them perfect for watching widescreen displays like DVDs, as well as traditional television shows.

What are the Differences between LCD and Traditional TVs?

LCD televisions, flat panel computer monitors and other devices have a number of built in advantages, and it is these advantages that have made them such a hit with technology buyers everywhere. Some of the many advantages of LCD technology include:

*Brighter display – the displays on LCD televisions are brighter than those on a traditional CRT television, due to the special way these displays work. While a traditional CRT television or monitor uses a tube to create the display, the LCT TV uses pixels, providing for a brighter display.

*Flicker free performance – the display of the LCD television or computer monitor will also be free of flicker, since the LCD display will have a constant source of light throughout the entire screen. Once the pixel is turned on it remains on. Contrast this to the design of the CRT television or monitor, which must refresh the screen periodically with a ray of light moving down the monitor or TV.

*Low power consumption – another big advantage of the LCD TV is its superior energy efficiency. LCD televisions will be up to 65% more energy efficient than traditional televisions, helping to protect the environment while saving you money.

*Ultra slim design – it is of course the thin and sleek design that turns heads and gets the attention of buyers. LCD displays can be as thin as 49mm (just over 19 inches), meaning that these TVs can be placed virtually anywhere.

*Wall mountable designs – Many LCD TVs are so thin that they can be hung on the wall as you would hang a picture. It is important of course to purchase a wall mounting bracket that is suitable for holding the weight of the unit.

A Guide to Some LCD TV Terms

If you are in the market for an LCD TV, you will likely hear a number of new, and sometimes confusing, terms bandied about. It is important to understand what these words mean to you, the television technology shopper.

*Aspect Ratio – the aspect ratio of the TV helps to determine its suitability for watching movies and television programming in true widescreen format. While the traditional television has always used a aspect ratio of 4:3, i.e. 4″ wide, 3″ high, the typical LCD television uses an aspect ratio of 16:9, providing a truer widescreen picture perfect for watching DVD and VHS movies, as well as traditional television programming.

*Candela – one of those words you may hear from time to time is candela. Put simply, the candela is a standard unit of brightness, and it is equivalent to the number of candles that would be required to produce the same intensity of light. Therefore a rating such as 450 cd/m2 means that it would take a concentration of 450 candles in a square meter area to produce the same amount of light.

*Contrast Ratio – the contrast ratio is simply the difference in intensity of light between the darkest black and the brightest white on the display. The higher the contrast ratio the sharper and cleaner the picture will be.

*HDTV – high definition television, or HDTV for short, is quickly becoming the standard for television signal technology, and it is important to look for an LCD TV that is HDTV ready.

*Inputs – the TV inputs are important if you plant to connect a DVD player, VCR, game console, computer or other device to the LCD display panel. There are many different types of inputs, and it is important that the TV you choose provide a number of different options for getting signals to the device. A TV with a great many inputs will allow you to connect a number of different devices to the TV, greatly enhancing its versatility and its value.

It is also important to make sure that LCD TV you choose has the proper tuner for playing the TV signal you have coming in to the house. Many plasma screen and LCD TVs will lack a built in tuner, meaning that they will need to pick up that television signal from a cable box, satellite TV box, DirectTV signal or other similar device. It is important to make sure you understand the type of tuner that comes with the TV you are considering, and it is important to purchase all the accessories you will need when buying the TV.

Speaking of accessories, it is important to buy only the highest quality component cabling to connect that LCD display to your DVD player, VCR, Laser Disk player, computer or other device. The highest quality cables will provide the best picture and sound quality, which will further enhance the display of the LCD TV you have chosen.

It is also important, of course, to get the very best price you can on the LCD TV you want. The suggested retail price of the typical LCD TV will vary according to a number of factors, such as the size of the display, the thinness of the display and the quality of the manufacturer. It is important to shop around as much as possible, and to read the reviews of all the models you are considering.

Finally, the ability to play several different television signal formats, such as PAL, NTSC and SECAM, is an important consideration. Different parts of the world use different formats for television signals and video products, and buying one of these multisystem LCD TVs is a good way to make it more versatile and useful while getting the best value for your money.

For more information see: http://www.planetomni.com

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PAL Standard

PAL technology is a colour encoding system used in broadcast television systems in a larger section of the world. The other common standards are NTSC and SECAM. PAL is an analogue broadcasting system and is a standard which uses in all 625 alternating lines. It is used on 50Hz power frequency cycle and operated in those countries where such frequency is the standard specification of its electrical power.

PAL was introduced as a standard in the year 1967 and has eight different types – PAL B, PAL G, PAL H, PAL D, PAL I, PAL K, PAL K, PAL N and PAL M. These offshoots of PAL have different specifications. PAL is used in China, India, Indonesia, Israel, Laos, Nepal, Pakistan, Thailand, Lebanon, Iraq, Iran, and United Kingdom, some European countries, some countries in South America and also in Africa.

Within Europe, France, along-with some of its neighbours, use SECAM technology, where-as, rest of the Europe uses the PAL standard. It is the dominant standard in the world, with the United States and Japan using the NTSC standard. PAL delivers 625 lines at 50 half frame per second and works on 50Hz power cycle.

NTSC

NTSC is the technology which sets the standard in television and video standard in the United States and provides a composite video signal having a refresh rate of about 60 half-frames per second, interlaced. A frame consists of a packet of data and in this case it would be a packet of composite video signals that a frame would contain. NTSC contains 525 lines and can contain 16 million colours. A composite video would mean a video signal in which all the colours are present, such as, red, blue, and green signals. It may also consist of audio signals at times. These are mixed together to form the composite video signal.

NTSC is essentially an analogue system, developed in the United States and in use in Canada, Japan, South Korea, the Philippines, the United States, and some other countries, mostly in the Americas. The refreshing rate of NTSC standard is 60Hz, and consists of 525 lines per frame. Out of these 525 lines, 485 carry the video information, with the rest are sync pulses, which are not visible. The bank lines have been deliberately put there to give time to the electronic gun in a television to reposition itself.

SECAM

SECAM is an analogue colour television system, first used in France, as a video standard, at the early part of 1960. It is historically the first European colour television standard. SECAM uses the same bandwidth as PAL but transmits colour sequentially. It runs on 625 lines per frame and uses the same frame rate as PAL, 25 frames per second. SECAM is used in France and former French colonies. It is also used in the former communist countries in Europe. Due to the same characteristics that SECAM has with PAL, especially as far as resolution and frame-rate are concerned, DVDs, VCDs, and SuperVHS use PAL internally, but before the signal is available at the output, the colour encoding is changed to SECAM to be displayed on a SECAM TV.

Due to the incompatibility in the video standards, video tapes from one region cannot be viewed in the television of another country, which has a different standard. This means, that a video tape from the United Kingdom cannot be viewed in the United States. The VCR has no capability to convert a PAL video tape to NTSC for viewing. Multi-system VCRs can play video tapes of all standards but it cannot convert the standard to make the video standard compatible with the existing standard of a television. Solution to this problem is to have a VCR with the capability of converting the output signal into a compatible standard for viewing it on a television. This multi-system VCR would have to have a built-in converter for the purpose.

A basic multi-system VCR does not have such a converter built in and a separate stand-alone converter is required to be used, in between the VCR and the television or otherwise you would need a multi-system TV to view the tape. A multi-system TV also has a converter built in, and any VHS tape can be played in any basic multi-system VCR for viewing. Suppose you need to view a PAL video tape on a NTSC television. You shall not be able to view the tape, unless your VCR is a multi-system one and has an inbuilt converter. The PAL tape is read by the VCR and converted to NTSC signals when the output of the VCR is being applied to the TV. If your multi-system VCR does not have a converter, you must have a multi-system television in-order that you may view the tape. The other alternative would be to hook up an external converter in between your multi-system VCR and your NTSC television, when you can view that video tape.

In converting PAL into NTSC, the point to remember is that NTSC video standard has a resolution of 720×480 and a frame rate of 30 frames per second, while PAL has a resolution of 720×576 with a frame rate of 25 frames per second. Therefore, from the above specifications, it can easily be determined that PAL has a better picture quality than NTSC, while NTSC has a better motion picture display because of its higher refresh rate.

Tenlab offers Tenlab converters which is capable of converting any of the video standards into the other. These are stand alone video broadcast standard converters, supporting PAL, SECAM and NTSC. The converter equipment connects to the VCR output with the converter output going into the television’s signal input. Therefore, if you are playing a PAL video tape/disc on your multi-system VCR/DVD, the output of the converter is available as a NTSC standard, compatible with the standard of your television.

Some of the Tenlab models stabilise the picture processing, using a bult-in time corrector and has a video enhancer to provide you with a crisp and clearer picture quality. Tenlab converters are also used by number of corporations. The converters are used exclusively for their professional applications such as worldwide satellite transmissions, MTV Latin America and Gulfstream Aerospace for their on-board multi-system entertainment systems.

Tenlab was established in the year 1988 with a mission to create products solving incompatibility between the different standards existing in video systems around the world. The company introduced the first NTSC VCR capable converter, playing other standard video tapes. Since then Tenlab has gone on to introducing new models and offered upgrading the older ones to the new standards.