Plasma TV

Like all other televisions, plasma screens are measured diagonally. Plasma TVs range in size from 32 inches to 63 inches, with typical sizes being:

	»		32 inches
	»		37 inches
	»		40 inches
	»		42 inches
	»		43 inches
	»		46 inches
	»		50 inches
	»		60 inches
	»		61 inches
	»		63 inches

Through marketing evolution 32, 37, 42, 50, and 60 inch screens have emerged as the most popular sizes, with 42 inch and 50 inch sizes dominating.

All plasma displays offer 16:9, otherwise known as widescreen aspect ratio screens with ‘16’ relating to the width and ‘9’ relating to the height. In contrast, almost all conventional TVs have been 4:3 relational aspect ratio screens.

EDTV is equivalent to 852x480 lines or 480 progressive (480p) resolution. HDTV is equivalent to a minimum of 1080 interlaced (1080i), 720 progressive (720p), or as high as 1080 progressive (1080p) resolution. Typically, the larger the plasma display, the higher the native resolution capability, however, many manufacturers offer multiple grades of the 42 inch sets (the most popular size). For example, one set will offer EDTV or 852 x480 resolution, while a more upscale set will display HDTV 1024x768 (XGA) or as high as 1024x1024 resolution. Some larger plasma sets in the 50 to 63 inch diagonal range offer HD resolution as high as 1365x768.

Due to higher manufacturing costs, High Definition plasma televisions have higher price tags than similar-featured Extended Definition sets. Despite the higher cost, HD plasma displays may or may not offer better viewing quality than ED plasma displays. Typically, High Definition sets will look better with HD resolution signals, while ED resolution sets will tend to look better when viewing non-HD signals from sources such as satellite TV, cable, or DVD. The reason for this is simple: there is relatively little processing involved in the transfer of Extended and Standard Definition source material to ED plasma displays; whereas the circuitry in HD sets must highly process ED source material. Subsequently, video quality is compromised. The greatest disparity between HD and ED sets can be seen in the ability of HD sets to accurately display detail and to eliminate pixellation, specifically with HD source material. High Definition TVs typically have improved scaling processing, which results in a smoother, more natural looking picture.

Like traditional tube TVs, but unlike rear projection televisions and most LCD sets, plasma TVs are not overly sensitive to off-axis viewing. Most plasma sets offer viewing angles as wide as 160 degrees, top-to-bottom and side-to-side from the center. This opens up seating arrangement possibilities within the consumer’s viewing rooms.

There are two issues to consider with plasma technology. They are:

	1)		Sensitivity to high altitude
	2)		Screen burn-in

Plasma sets are sensitive to high altitudes because the thinner air causes increased stress on the gases inside the glass substrate envelope. This stress dramatically increases the amount of power required to run them. Increased power requirements lead to increased cooling requirements which, in turn causes the power supply to over work. This leads to either louder fan buzzing noise and/or overheating of the power supply. In drastic situations, thermal overload occurs, shutting down the power supply in the set.

Screen burn-in is another factor to be considered when purchasing a plasma TV. Static images that are displayed for a period of time may begin to etch a shadow in the display panel. Although burned-in images can occur in lower grade sets in as little as 30 minutes, most burn-in requires static on-screen imagery to remain for several hours at a time. The higher quality sets maintain ‘refresh’ circuitry which minimizes the effects of static imagery. Normally, burn-in can be washed-out by displaying action or motion scenes with gray images or full color ranges over several hours.

Plasma TV design lends itself extremely well to this popular method. There are 3 means of wall mounting. The first method is flat wall mounting. Flat wall mounting holds the plasma TV within 2 inches from the wall giving it a sleek, unobtrusive appearance. It is the best option for economizing on room space.

The second method of wall mounting is by means of a tilt wall mount. The tilt wall mount can be either up and down or side to side. The up and down method allows the set to tilt downward after being secured to the wall. The tilt is variable and relatively small, from 0 degrees to about 15 degrees. This allows more direct viewing when the set is installed at heights above eye level, for example, above fireplaces or cabinetry. The side to side method also allows variable movement, from 0 degrees to about 20 degrees. Combination up and down and side to side mounts are also available.

The third wall mounting option is by use of an articulating arm. This swivel mechanism allows the viewer to manipulate the TV from a fold-up position close to the wall to a position over a foot distance from the wall. All articulating wall mounts also allow the TV to move side to side as much as 120 degrees in either direction with a top to bottom tilt of 0-10 degrees.

Like wall mounts, ceiling mount options can be flat, up and down, or side to side. Likewise, combination up and down and side to side mounts are available. The mounting poles are sometimes variable in length and extensions can be added on. Typically, mounting poles come in 12 inch to 60 inch lengths.

These TV bases are designed to attach to the back of the plasma TV and allow the TV to sit on flat surfaces such as credenzas and tables, and inside wall units and armoires. The table stands usually raise the TVs ½ inch to 2½ inches from table top to TV bottom. In most cases, these table stands are optional accessories, however some models are offered with the stands as standard equipment with the set.

All of the methods of mounting and usage utilize mechanisms that are designed and built by either the respective plasma manufacturer or an after market manufacturer. Each plasma model requires a mount specific to that TV, although manufacturers will often design a mount to fit a number of their models. Research and planning is often required to ensure the correct fit.

Some skilled trades, such as electrical and carpentry contractors offer adequate plasma TV mounting services. These trades people have the greatest understanding of construction requirements. Their services are most useful in circumstances where wall or ceiling mounting issues exist.

Low voltage contractors are relative newcomers to the building trades world. These trades people specialize in the sale and installation of low voltage wiring and sometimes supply the consumer electronics products (such as plasma and LCD TVs) that utilize the low voltage. Many low voltage firms are subcontracted by general building contractors to run low voltage wiring, but some possess the skills and manpower to install plasma TVs in retrofit venues.

High quality services can be obtained by retailers that specialize in the sale and customized installation of consumer electronics such as plasma televisions. These firms possess an understanding of home architecture and design, plus they have strong knowledge of audio/video technology. Many of these specialists maintain professional installation technicians on-staff, but normally will install only the products that they sell.

One of the most appealing features of plasma TV technology is that all sets are designed to interface directly to computers via a built-in 15 pin VGA connector. In addition to VGA, most sets offer at least one other connection possibility, such as composite, component video, and/or S-video. Most higher-end plasma displays are generally designed with all four video connection possibilities: VGA, component video, composite video, and S-Video, plus stereo composite audio inputs. The benefit of multiple inputs is the ability to interface several video sources such as DVD player/recorders, video cassette player/recorders, satellite receivers, cable boxes, and video hard drives directly to the TV. Some new models have slots, similar to computer board slots, which enable quick and easy addition of input connectors, such as component video or S-video.

Until the most recent generation of plasma models, the majority of plasma sets have been designed and utilized as stand-alone monitors without built-in TV tuners. That means the viewer has required the use of an independent tuner, such as a VCR tuner, a cable TV tuner box, or a digital satellite tuner box to access and change channels. Currently, most of the models from Sony, Panasonic, etc. that we offer include built-in TV tuners. Today, more manufacturers are beginning to offer sets with built-in tuners. With the roll-out of new connectivity such as DVI (Digital Visual Interface) and HDMI, some manufacturers are designing proprietary set-top boxes that double as cable-ready/off-air TV tuners as well as connection hubs. These connection hub boxes are usually installed along with the source equipment and allow hook-up of the various video sources, such as DVD’s, VCRs, HD tuners, and recording hard drives. The box then interfaces to the plasma monitor via the DVI or HDMI cable. Currently only some upper-end, High Definition plasma models offer this method of proprietary box/TV monitor package.

In order for a plasma set to have High Definition ‘ready’ capability, it must have the following features:

	1)		Interface capability with High Definition resolution tuner sources, such as cable TV boxes, Digital Satellite System (DSS) boxes, and/or off-air HD boxes. This interface is accomplished via component video, DVI, or HDMI inputs.
	2)		The ability to process resolution of 720p and/or 1080i at a minimum.

Given these parameters, HD ‘ready’ plasma sets include monitors (plasma sets without tuners), and televisions (plasma sets manufactured and sold with tuners).

In contrast, High Definition ‘built-in’ signifies the addition of a High Definition tuner, either on-board or out-board, included in the package of each respective model, along with the display. A TV tuner with HD ‘built-in’ implies the ability to pick up and decode only off-air broadcasts in High Definition resolution. Separate cable and/or DSS decoder boxes are also required in order to decode and watch either cable or DSS transmissions.