| Bandwidth: |
The frequency range allocated to any communication circuit. |
| Baseband: |
A signal without a carrier. A television camera produces baseband signals. Television monitors which accept baseband signals do not require an R.F. tuner or an I. F. detector section. Baseband audio is pure audio as from a tape recorder. Baseband video contains no audio information. For basebands to be used by a normal television, it must be modulated at the frequency of the particular channel into which it is to be fed. |
| BNC Connector: |
A weatherproof twist lock coax connector standard on commercial video equipment and used on some brands of satellite receivers. |
| Boresight: |
The direction along the principle axis of either a transmitting or a receiving antenna. |
| Broadband: |
A device that processes a signal (s) spanning a relatively broad range of input frequencies. |
| Cable-Ready Television: |
A television receiver that can receive unscrambled cable television channels without the use of a converter. |
| Carrier: |
A pure-frequency signal that is modulated to carry information. In the process of modulation it is spread out over a wider band. The carrier frequency is the center frequency on any television channel. |
| CATV: |
An abbreviation for Community Antenna Television- another name for cable TV. |
| CCD: |
Charge coupled device. In this device charge is stored on a capacitor which are etched onto a chip. A number of samples can be simultaneously stored. Used in MAC transmissions for temporarily storing video signals. |
| Channel: |
A segment of bandwidth used for one complete communication link. |
| Clipping: |
The shearing off of the peaks of a signal. For a picture signal, this may affect either the positive (white) or negative (black) peaks. For a composite video signal, the synchronizing signal may be affected. |
| Coaxial Cable: |
The most commonly used means of signal distribution, consisting of a center conductor and a cylindrical outer conductor (shield). A cable for transmitting high frequency electrical signals with low loss. It is composed of an internal conducting wire surrounded by an insulating dielectric which is further protected by a metal shield. The impedance of coax is a product of the radius of the central conductor, the radius of the shield and the dielectric constant of the insulation. In an SMATV system, coax impedance is 75 ohms. |
| Color Bar: |
A test signal, typically containing six, basic colors: yellow, cyan, green, magenta, red, and blue, which is used to check the chrominance functions of color TV systems. |
| Combiner: |
An active or passive device that serves to combine several signals into one output while maintaining a high degree of isolation between each input. |
| Composite Baseband Signal: |
The complete audio and video signal without a carrier wave. Satellite signals have audio baseband information ranging in frequency from zero to 3400 Hertz. NTSC video baseband is from zero to 4.2 MHz . PAL video baseband ranges from 0 to 5.5 MHz. |
| Composite Video Signal: |
The complete video signal consisting of the chrominance and luminance information as well as all sync and blanking pulses. |
| Contrast: |
The ratio between the dark and light areas of a television picture. |
| Converter: |
A device for changing signals from one frequency to another frequency. A device used to transfer signals from a channel of one frequency to another. |
| Cross Modulation: |
A form of distortion where modulation of an interfering stating appears a modulation of the desired station. A form of interference caused by the modulation of one carrier affecting that of another signal. It can be overloading an amplifier as well as by signal imbalances at the headend. |
| Cross Talk: |
Interference between adjacent channels often caused by cross modulation. Leakage can occur between two wires, PCB tracks or parallel cables. |
