This is a basic measurement of how much information is on the screen. It is usually described as "some number" by "some number". The first "some number" is the horizontal (across the screen) resolution and the second "some number" is the vertical resolution (down the screen). The higher the number, the better, since that means there is more detail. Some examples:

NTSC VHS: 240 x 485

NTSC broadcast: 330 x 485

NTSC laserdisc: 425 x 485

ITU-R BT.601 (525/60): 720 x 485

Computer screen: 1280 x 1024

The maximum definition a particular system is capable of reproducing. Resolution is measured in the number of discrete observable lines that can be reproduced on a system. The higher the resolution a system is capable of producing, the sharper the picture will appear. In TV, resolution is measured in vertical and horizontal lines or the total number of observable black to white line transitions observable in the picture. Horizontal resolution is limited by the bandwidth of the television circuit, while vertical resolution is limited by the total number of TV scan lines. A high-resolution video camera or monitor can display 700 horizontal lines of resolution and 480 vertical lines or 700 x 480 resolution. While influenced by the number of pixels in an image (for high definition approximately 2,000 x 1,000, broadcast NTSC TV 720 x 487, broadcast PAL TV 720 x 576), note that the pixel numbers do not define ultimate resolution but merely the resolution of that part of the equipment. The quality of lenses, display tubes, film process and film scanners, etc., used to produce the image on the screen must all be taken into account. This is why a live broadcast of the Super Bowl looks better than a broadcast recorded and played off of VHS, while all are NTSC or PAL.

Amount of detail in the video image is measured along both the horizontal and vertical axes. In digital systems, resolution is the number of pixels on a display surface. Computer CRT resolutions are usually given as the number of pixels per scan line and the number of scan lines, e.g. 640 x 480. Video resolution is measured in terms of lines of detail per horizontal scan line (horizontal resolution) and total number of scan lines (vertical resolution).

The clarity or graininess of a video or computer image as measured by lines or pixels; the smallest resolvable detail in the image. The perceivable detail, or the ability of an image reproducing system to reproduce fine detail

Temperature
Operating: -10°C to 50°C
Storage: -40°C to 71°C

Functionality is not adversely affected within these operating guidelines.

Relative Humidity
Functional operating limits: 90% RH at max 35°C
Functional storage limits: 90% RH at max 35°C for 240 hrs, noncondensing

Thermal Cycling
The touchscreen shall be capable of functioning normally after the completion of fifty thermal cycles from room conditions to 70° C, back to room temperature; and then to -40° C and back to room temperature at a rate not to exceed 2º C per minute and with a one hour soak at each temperature extreme.

Immersion
The touchscreen shall be capable of functioning normally after having its lower edge immersed in water containing 5% isopropyl alcohol to a height one third of the overall height of the touchscreen, for a period of six hours.

Water Spray
The touchscreen shall function normally and not be damaged by running water applied to the active area.

Chemical Resistance
The active area of the touchscreen is resistant to the following chemicals when exposed for a period of one hour at a temperature of 70°F (21°C):

Industrial Chemicals
Acetone, Methylene chloride, Methyl ethyl ketone, Isopropyl alcohol, Hexane, Turpentine, Mineral spirits, Unleaded Gasoline, Diesel Fuel, Motor Oil, Transmission Fluid, Antifreeze.

Food Service Chemicals
Ammonia based glass cleaner, Laundry Detergents, Cleaners (Fantastic, Formula 409, Joy, etc.), Vinegar, Coffee, Tea, Grease, Cooking Oil, Salt.

Altitude
Operating
The touchscreen shall be capable of operating at an altitude of 10,000 feet above sea level.

Storage
The touchscreen shall be capable of being stored without damage at an altitude of 50,000 feet above sea level.

Vibration
The touchscreen shall not be damaged by being subjected to a vibration of 0.01 inches peak to peak excursion, at a frequency of 5 to 455 Hz, for a period of 15 minutes in each of three axes.

Shock
The touchscreen, in its standard shipping container, shall be capable of withstanding the drop test of Project 1A of the National Safe Transit Association Program Pre-shipment Test Procedures (10 drops from a height of 30 inches).

Impact Strength
Spherical touchscreens, when supported on their four corners, shall be capable of withstanding a load of 20 pounds applied in the center of the active area through a stylus of one inch diameter.

Distributed Load
Spherical touchscreens, when supported on their four corners, shall be capable of withstanding a load, evenly distributed over their surface, of 40 pounds.

How an AccuTouch Touchscreen Works
The Parts of a Touchscreen
The AccuTouch five-wire resistive touchscreen uses a glass panel with a uniform resistive coating. A thick polyester coversheet is tightly suspended over the top of a glass substrate, separated by small, transparent insulating dots. The coversheet has a hard, durable coating on the outer side and a conductive coating on the inner side.

What Happens During a Touch

When the screen is touched, it pushes the conductive coating on the coversheet against the coating on the glass, making electrical contact. The voltages produced are the analog representation of the position touched.

How the Touchscreen Controller Interprets Screen Measurement

When the controller is waiting for a touch, the resistive layer of the touchscreen is biased at +5V through four drive lines, and the coversheet is grounded through a high resistance. When the touchscreen is not being touched, the voltage on the coversheet is zero. The voltage level of the coversheet is continuously converted by the analog-to-digital converter (ADC) and monitored by the microprocessor on the controller.

When the touchscreen is touched, the microprocessor detects the rise in the coversheet voltage and begins converting the coordinates as follows:

A The microprocessor places the X drive voltage on the touchscreen by applying +5V to pins H and X and grounding pins Y and L. An analog voltage proportional to the X (horizontal) position of the touch appears on the cover sheet at pin S of the touchscreen connector. This voltage is digitized by the ADC and subjected to an averaging algorithm, then stored for transmission to the host.
B Next, the microprocessor places the Y drive voltage on the touchscreen by applying +5V to pins H and Y and grounding pin X and L. An analog voltage proportional to the Y (vertical position of the touch) now appears on the coversheet at pin S of the touchscreen connector. This signal is converted and processed as described above for the X position

Why the Averaging Algorithm is Important
The averaging algorithm reduces noise resulting from contact bounce during the making and breaking contact with the touchscreen. Successive X and Y samples are tested to determine that their values differ by no more than a certain range. If one or more samples fall outside this range, the samples are discarded and the process is restarted. This is continued until several successive X samples (then Y samples) fall within the range. The average of these values is used as the X and Y coordinates respectively.

Once independent X and Y samples are obtained, coordinate pairs are sampled to eliminate the effects of noise. If a sample does not fall within an internal range, all X and Y coordinates are discarded and the independent X and Y sequence is restarted. Once acceptable coordinates have been obtained, an average coordinate is determined and communicated to the host processor.

Video Alignment
The X and Y values are similar to Cartesian coordinates, with X increasing from left to right and Y increasing from bottom to top. These absolute coordinates are arbitrary and unscaled, and will vary slightly from touchscreen to touchscreen. The AccuTouch controller can be calibrated for video alignment. This aligns the touchscreen coordinate system with the display image, reorients each axis, and scales the coordinates before they are transmitted to the host computer.

X- and Y-axis Measurements Originate from the Glass
AccuTouch five-wire technology utilizes the bottom glass substrate for both X- and Y-axis measurements. The flexible coversheet acts only as a voltage-measuring probe. This means that the touchscreen will continue working properly even with nonuniformity in the cover sheet's conductive coating. The result is an accurate, durable, and reliable touchscreen that offers drift free operation.

 
 A special type of cabinet in which equipment is installed. Most common are racks that will accept equipment that is 19 inches across with places for it to be screwed into the front. Many rack will have ground busses, power strips and back doors. Some will provide air conditioning vents.

 
 One rack unit or U is 1.75 inches in height. Most 19" rack equipment in broadcasting is specified to be mounted in increments of Us in heighth. For example, 2 Us would be 3.5 inches high.

   ANSI standard defining the single-ended (unbalanced) interconnection scheme for serial data communications.

   A medium range (typically up to 300 m/1000 ft or more) balanced serial data transmission standard. Data is sent using an ECL signal on two twisted pairs for bi-directional operation. Full specification includes 9-way D-type connectors and optional additional signal lines. RS-422 is widely used for control links around production and post areas for a range of equipment.

   A medium range (typically up to 300 m/1000 ft or more) balanced serial data transmission standard. Data is sent using an ECL signal on two twisted pairs for bi-directional operation. Full specification includes 9-way D-type connectors and optional additional signal lines. RS-422 is widely used for control links around production and post areas for a range of equipment.

A 19-inch rack is a standardized (EIA 310-D, IEC 60297 and DIN 41494 SC48D) system for mounting various electronic modules in a "stack", or rack, 19 inches (482.6 mm) wide. Equipment designed to be placed in a rack is typically described as rack-mount, a rack mounted system, a rack mount chassis, subrack, or occasionally, simply shelf. The slang expression for a subrack (generally 1U = 1.75 in = 44.45 mm height) is "pizza box" due to the similarity in size and shape, see also pizza box form factor. Most racks are sold in the 42U form: that is, a single rack capable of holding 42 1U pizza box servers.

Because of their origin as mounting systems for railroad signaling relays, they are still sometimes called relay racks, but the 19-inch rack format has remained a constant while the technology that is mounted within it has changed to completely different fields. This standard rack arrangement is widely used throughout the telecommunication, computing, audio, entertainment and other industries, though the Western Electric 23-inch standard, with holes on 1-inch centers, prevails in telecommunications.

Typically, a piece of equipment being installed has a front panel height 1/32-inch (.03125") less than the allotted number of U's. Thus, a 1U rackmount computer is not 1.75-inches tall but is 1.71875-inches tall. 2U would be 3.46875-inches instead of 3.5-inches. This gap allows a bit of room above and below an installed piece of equipment so it may be removed without binding on the adjacent equipment.

Serial Advanced Technology Attachment (SATA, IPA: /'se?t?/ or /'sæt?/) is a computer bus primarily designed for transfer of data between a computer and storage devices (like hard disk drives or optical drives).

The main benefits are thinner cables that let air cooling work more efficiently, faster transfers, ability to remove or add devices while operating (hot swapping), and more reliable operation with tighter data integrity checks than the older Parallel ATA interface.

It was designed as a successor to the legacy Advanced Technology Attachment standard (ATA), and is expected to eventually replace the older technology (retroactively renamed Parallel ATA or PATA). Serial ATA adapters and devices communicate over a high-speed serial cable.