The final piece of hardware on a cable designed for CATV or DBS or other signal distribution applications. It is cylindrical with a center pin sticking out, that plugs into the set-top box, cable ready TV, satellite receiver, or VCR.

Indicates the brightness of the image formed by the lens, controlled by the iris. The smaller the F-number the brighter the image.

A term used to indicate the speed of a lens. The smaller the F-number the greater amount of light passes through the lens.

The part of the satellite system that collects and focuses satellite signals reflected by the antenna.

Also called optical fibers or optical fiber bundles. An assemblage of transparent glass fibers all bundled together parallel to one another. The length of each fiber is much greater than its diameter. This bundle of fibers has the ability to transmit a picture from one of its surfaces to the other around curves and into otherwise inaccessible places with an extremely low loss of definition and light, by a process of total reflection.

The view of the camera - in relation to the angle of view and distance of the object from the lens.

Referring to lenses - C mount = 15.5mm, CS mount = 12.5mm.

The point at which light passing through a lens is concentrated.

A frame consists of 2 interlaces fields. 25 Frames are created every second.

The quality of a Digital Surveillance Systems is often determined by the Total Frame Rate it can record at. The higher the Frame Rate, the higher the quality of recording and the more Real Time your CCTV recording will be - Real Time recording for 1 camera is 25 Frames Per Second (PAL).

An electronic method of capturing and storing a single frame of video. All slow scan transmitters include a frame store that holds the picture at the moment of alarm, while the control is being dialed up. When the link is confirmed, the picture is transmitted.

The method by which color and black and white sideband signals are interwoven within the same channel bandwidth.

The range of band of frequencies to which a unit of electronic equipment will offer essentially the same characteristics.

The portion of a composite picture signal which lies between the leading edge of the horizontal blanking pulse and the leading edge of the corresponding sync pulse.

Frequency Shifted Keying - a form of signaling employed by some coaxial born telemetry equipment.

An increase in voltage or power, usually expressed in dB.

A method of converting the minute electric currents produced by AI circuits, used by both AI & DD lenses.

A numerical value, or the degree of contrast in a television picture, which is the exponent of that power law which is used to approximate the curve of output magnitude versus input magnitude over the region of interest.

To provide for a linear transfer characteristic from input to output device.

A device used to lock the frequency of an internal sync generator to an external source.

A spurious image resulting from an echo.

Graded Index Profile - a measurement shown in the form of a diagram which illustrates how the quality of glass used in fibre optics alters gradually from the densest at the core to the optically less dense cladding.

A measurement, shown in the form of a diagram, which illustrates how the quality of glass used in optical fibre alters gradually, from densest at the core to the optically less dense cladding.

Variations in value from white, through shades of gray, to black on a television screen. The gradations approximate the tonal values of the original image picked up by the TV camera.

Caused by different earth potentials clearly seen as interference or humbars on a video signal.

Ground Loop Transformer - an isolation transformer with no direct contact between input and output.

Geosynchronous Orbit; satellites in geosynchronous orbit travel around the earth in an area approximately 22,300 miles from the surface at the same rate that the earth turns, therefore completing one revolution every 24 hours.

Direct cable connection between one product to another, used for control of equipment in simple systems.

When a modem complies with the Hayes AT command language used by most communication software packages.

A cable TV systems control center where incoming signals from satellites and other sources are put into the system. (Head End) The originating point of a signal in cable TV systems. At the head end, you'll often find large satellite receiving antennae. A central control device required within some LAN systems to provide such centralized functions as remodultaion, re-timing, message accountability, connection control, diagnostic control, and access.

The Homerun Wire is most often a single wire (usually an RG6 or RG59 coaxial cable) that runs from each apartment building's meter room to each apartment and is designed to deliver television or telephone services. Some of the modern day Homerun Wires are being used to deliver all services, cable and satellite television, telephone and fax and high-speed Internet connections.

Recording system used by VCR's, a record/playback head used by VCR's whereby the head rotates scanning the video tape in a helical path.

Refers to the resolution or number of pixels used to represent a single video image frame. Standard Definition refers to having about 350,000 pixels per frame, and High Definition refers to having about 2,000,000 pixels per frame, (or about 6 times more than SD).

A term used to describe a type of automatic sequential switcher, which will stop sequencing and remain on a single CCTV camera input displayed on the monitor when a switch or button is depressed. This switcher has only one monitor output.

The centre of a star topology network or cabling system. A multi-node network topology that has a central multiplexer with many nodes feeding into and through the multiplexer or hub. The other nodes do not usually directly interconnect. LAN hubs are increasingly popular with the growth of structured cabling and the need for LAN management.

Corresponds to colors such as red, blue, etcetera.

Electrical disturbance at the power supply frequency or harmonics thereof.

An industry term used to describe a auto-iris lenses inability to stabilize under certain light conditions.

A satellite that carries two or more different communications payloads (i.e., C-Band and Ku-Band).

Hertz - Cycles per second. The measure of frequency.

Camera caption or number displayed on a video signal.

A device that uses fibre optics to increase the sensitivity of a pick-up tube.

The plane at right angles to the optical axis at the image point.

Refers to the size of the image plane within a camera.

The input or output characteristic of a system component that determines the type of transmission cable to be used. The cable used must have the same characteristic impedance as the component. Expressed in ohms. Video distribution has standardized on 75-ohm coaxial and 124-ohm balanced cable.

-Per-View Technology that allows the consumer to purchase a movie or special event instantly via a computerized order processing center. This technology allows for the processing of a high volume of orders in a short time period.

The light that falls directly on an object.

The signal strength loss when a piece of equipment is inserted into a line.

Extraneous energy which tends to interfere with the reception of the desired signals.

A scanning process for reducing image flicker in which the distance from center to center of successively scanned lines is two or more times the nominal line width, and in which the adjacent lines belong to different fields.

Term used in multiplexing. When a camera is alarmed, be it via external means (PIR) or by activity detection, then it is recorded every other frame.

A technology of CCD design, where rows of pixels are output from the camera. The sensor's active pixel area and storage register are both contained within the active image area. This differs from "frame transfer" cameras that move all active pixels to a storage register outside of the active area.

The internal generation of sync pulses in a camera using a crystal controlled oscillator. This is needed on non-mains powered cameras.

A CCTV Camera that can transmit video and audio over TCP/IP network. An IP Camera can connect to a local network and streams it's video over the network to a Network Video Recorder. IP Cameras can come with additional features including Power over Ethernet , wireless lan connection and Mega Pixel Resolution.

An IR Cut Filter is an extra filter inside the camera that moves behind the camera lens when it gets dark. A camera with an IR Cut Filter will produce very high quality images in low light conditions.

Lighting that is above the visible wavelength, used for discrete illumination in CCTV systems.

Ingress Protection Scale - 2 numbers indicating the protection level of an outside enclsure - e.g. IP68

A device capable of receiving and tuning satellite signals. The output of the receiver can be either Baseband video for use with video monitors or RF for use with standard TV sets.

A mechanical diaphragm which can be controlled manually or automatically to adjust the lens aperture.

Difference in focus of a camera's field of view between white and IR lighting.

Method of sending video signals and/or data over free space, distance and quality of transmission is affected by environmental conditions such as fog and rain.

Intensified Silicon Intensified Target - usually used for extreme low light CCTV or X-Ray machines.

An amplifier with input circuitry and output circuitry designed to eliminate the effects of changes made at either upon the other.

A hypothetical antenna having equal radiation intensity in all directions.

Small, rapid variations in a waveform due to mechanical disturbances or to changes in the characteristic of components. Supply voltages, imperfect synchronizing signals, circuits, etc.

Joint Photographic Experts Group - an image compression technique used for still images.

Pulses generated, normally by the camera, to tell other pieces of equipment that a picture, or one line of a picture, is about to start.